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The effects of a six week depth jumping program on the vertical jumping ability of figure skaters Keohane, Anne Louise 1977

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THE EFFECTS OF A SIX WEEK DEPTH JUMPING PROGRAM O N THE VERTICAL JUMPING ABILITY O F FIGURE SKATERS by A N N E LOUISE KEOHANE B.P.E., University of Ottawa, 1973 B.Ed., Queen's University, 1974  A THESIS SUBMITTED IN PARTIAL FULFILLMENT O F THE REQUIREMENTS FOR THE DEGREE O F MASTER OF PHYSICAL EDUCATION in the School of Physical Education and Recreation We accept this thesis as conforming to the required standard  THE UNIVERSITY OF BRITISH COLUMBIA Aprils 1977  Anne Louise Keohane, 1977  In p r e s e n t i n g t h i s t h e s i s  in p a r t i a l  an advanced degree at the U n i v e r s i t y the L i b r a r y  s h a l l make i t f r e e l y  f u l f i l m e n t o f the requirements of B r i t i s h Columbia, I agree  available for  I f u r t h e r agree t h a t p e r m i s s i o n f o r e x t e n s i v e  r e f e r e n c e and copying o f t h i s  It  i s understood that copying or  thesis  permission.  Department of The U n i v e r s i t y  P h y s i c a l Education: o f B r i t i s h Columbia  2075 Wesbrook P l a c e V a n c o u v e r , Canada V6T 1W5  Date  May  l  r  1977  or  publication  o f t h i s t h e s i s f o r f i n a n c i a l g a i n s h a l l not be a l l o w e d w i t h o u t my written  that  study.  f o r s c h o l a r l y purposes may be g r a n t e d by the Head of my Department by h i s r e p r e s e n t a t i v e s .  for  i  ABSTRACT  With the current emphasis on jumps and jump combinations in competitive figure skating, training methods to improve jumping ability would be of great benefit to figure skaters.  To be a successful jumper, a figure skater needs leg power in addition to skill  and technique. Jump combinations, comparatively new elements of free skating, require leg power combined with balance, positioning, and timing.  To develop the  leg power required in jumping, depth jumping was tested as a potential training method for skaters.  Depth jumping, a relatively new training technique, is designed to improve  leg power and the reactive ability of jumpers.  In performing a depth jump, the athlete  jumps down from an elevated surface and immediately takes off for a second jump upon contact with the floor. The emphasis is on immediate takeoff after landing from a previous jump so that the athlete learns to use the elastic recoil of muscle to produce an additive effect on jump height. The purpose of this investigation was to determine the effects of a six week depth jumping program on vertical jumping ability on and off the ice. A subproblem of this study was to determine the relationship between vertical jumping ability on the ground and on the ice. The sample consisted of twenty-seven female figure skaters from the Vancouver area (mean age 14.9 years) who volunteered to take part. Subjects were randomly assigned to experimental (n = 14) and control (n = 13) groups.  The experimental group  participated in a six week depth jump training program conducted off the ice in addition to their regular training on and off the ice. The control group did not participate in the depth jump program but participated in their regular training on and off the ice. The depth jump program consisted of two preparatory exercises and five training exercises performed from various heights (12", 15", 18", 21").  Training sessions were  held twice per week for the first three weeks and three times per week for the last three weeks. The study included a total of sixteen training sessions. All subjects were tested at the beginning, middle, and end of the study on the Sargent Jump Test and filmed (pre and post only) on the ice performing a single loop, single loop combination jump. Films were analyzed on the Vanguard Motion Analyzer. The following hypotheses were tested for significance at the .05 level: 1.  As a result of depth jump training, there is a significant increase in vertical jumping ability on the ground.  2.  As a result of depth jump training, there is a significant increase in the height of the second jump of a single loop, single loop combination jump.  3.  There is a positive linear relationship between vertical jumping ability on the ground and vertical jumping ability on the ice.  Multivariate analysis of variance revealed that hypothesis *1 is supported at the .01 level and hypothesis *2 is supported at the .05 level of significance.  The Pearson  Product Moment Correlation showed that hypothesis 3 is also accepted at the .05 level. #  iii  TABLE OF CONTENTS Chapter 1.  2.  Page  INTRODUCTION  1  STATEMENT OF THE PROBLEM  4  DEFINITIONS  4  HYPOTHESES  5  DELIMITATIONS  6  LIMITATIONS  .  6  SIGNIFICANCE OF THE STUDY  7  REVIEW OF LITERATURE Studies on Vertical Jump Depth Jumping  3.  METHODS AND PROCEDURES  8 8 13 21  Subjects  21  Time and Duration of the Study  21  Personnel  22  TESTS  22  Sargent Jump Test  22  Film Analysis  23  iv  TABLE OF CONTENTS Chapter  Page PROCEDURES FOR THE DEPTH JUMP TRAINING PROGRAM  . . . .  Warm Up Exercises  26  Preparatory Exercises Using A 6" Box  26  Depth Jump Exercises . . . . . . . .  27  EXPERIMENTAL DESIGN  .  STATISTICAL TREATMENT . . 4.  24  29 29  RESULTS A N D DISCUSSION  31  Results: The Effect of Depth Jump Training on Vertical Jump and Skating  32  Discussion  36  Results: The Relationship Between Jumping Ability On and Off the Ice . . .  5.  39  Discussion  41  Implications For Skating Coaches  44  SUMMARY A N D CONCLUSIONS  .  47  REFERENCES APPENDICES  50 .  55  APPENDIX A: Individual Raw Scores APPENDIX B: Sample Calculations  56 . .  64  V  TABLE O F CONTENTS Page APPENDIX C: Computer Program and Output Computation of Jump Height from Film Data  66  APPENDIX D: Biomechanical Description of Connective Section of The Single Loop, Single Loop Combination Jump  70  LIST OF TABLES Table  Page  1.  Depth Jump Height  25  2.  Outline of the Depth Jump Program  25  3.  Subject Data  31  4.  Observed Cell Means  32  5.  Improvement Scores  33  6.  F Values  35  7.  Pretest Correlation Coefficients  40  8.  Posttest Correlation Coefficients  40  vii  LIST O F FIGURES Figure  Page  1.  Experimental Design  29  2.  Improvement Trends Over the Six Weeks in Vertical Jump  34  VIII  LIST OF PLATES Plate 1.  Page Illustration of the Single Loop, Single Loop Combination Jump . . . .  72  ix  ACKNOWLEDGMENTS  The investigator would like to express sincere appreciation to the members of the committee for their guidance in this study and to the various individuals who assisted in other aspects of the study: B. Mason, for computer programming and testing; A. Mahrle, for translation of related literature and testing; C. Chamberlin, for construction of equipment; F. Mauer, for technical advice in filming; I. and Z. Savor, for translation of related literature; and to the subjects who participated in this study.  Chapter 1  INTRODUCTION  Athletes involved in jumping events are frequently looking for training methods which allow more efficient development of specific power (Wilt, 1975; Zanon, 1974; Verhoshanskiy, 1967). The main problem is to find exercises that are best suited for the specific type of power required in an event (Wilt, Cerutti, Embling, Toomsalu, Pross, McGuire, Schubert, 1974).  Because leg power is an extremely important  requirement in free skating performance (Zeller, 1973), there is a definite need for the development of power exercises designed specifically for competitive skaters. The emphasis in competitive figure skating today is on jumping - doubles, triples, and jump combinations (Dedic, 1973, May, 1976). Rule changes over the last few years have caused the emphasis to shift from a high value on compulsory figures to a greater importance on free skating.  In competition today, free skating  is worth seventy per cent of the total score and figures are worth only thirty per cent. Several years ago, figures were valued at sixty per cent of the total and free skating only forty per cent. Under previous regulations, a skater could be a superb figure skater and a poor free skater and still win a world championship.  Now, winning a  world championship seems to depend on: " . . . how much and how well you jump in the free skating, and how closely you trace the figures. " (May, 1976). The introduction of the compulsory free skating program by the International Skating Union (I.S.U.) in 1973 has led to a greater emphasis on jump combinations, the jump combination being one of the seven required elements of the short program. 1  2 A jump combination is a skating skill consisting of two jumps, one specified by I.S.U. rules and the other optional.  "The jump combined with the prescribed double jump,  may be the same jump or another double or triple jump. The second jump may either precede or follow the prescribed double jump.  No change of foot or turn is allowed  at any time between the two jumps, which must directly follow one another... " (I.S.U. Rule 323). In the short program, errors or omissions occur more often in the jump combination than any other element since errors can occur in the first jump, the second jump or in both jumps. The control, balance, timing, and leg power required in a combination jump make it one of the most difficult skills in figure skating.  In evaluating a com-  bination jump, a judge considers technique of the jumps, height, speed, distance, as well as the fluid connection of one jump to the other. The value of the combination is measured in relation to the degree of difficulty of the optional jump (BianchettiGarbato, 1976). The mark deductions for a failure or an omission on the jump combination is a higher deduction than for any other element, indicating the relative importance of jump combinations in free skating. To perform jumps in combination, a skater must have fast reactive ability. Descending from peak height of the first jump, the skater contacts the ice with considerable force, then must immediately take off for a second jump.  Landing from  the first jump requires a fast change over from absorbing force to applying force. "Depth jumping" described by Verhoshanskiy (1966), is a training technique designed to increase the reactive ability of jumpers. Consequently, the investigator feels that depth jumping would be an effective method of improving jumping ability in jump  3 combinations since it simulates the landing and immediate takeoff situations in skating jump combinations. Most competetive skaters in Canada are involved in some kind of off ice conditioning program to supplement skill practice on the ice. Running, circuit training, weight training, dance, and flexibility work are the major fitness training methods employed by skaters (Schutz and Coutts; 1974, 1975, 1976). Strength and power exercises with weights are currently used by skaters to improve jumping ability. These are necessary for basic strength preparation which must precede more specific jump training. It is important to point out that in comparison to other athletes, skaters show relatively poor leg power as measured by the Sargent Jump Test, a commonly accepted test of athletic power (Johnson and Nelson, 1974). The mean vertical jump of a group of male skaters attending a Canadian Figure Skating Association National Training Seminar in 1975 was 49.0 cm in comparison with a mean of 73.4 cm for top male volleyball teams (Toyoda, 1975).  In light of this fact, additional jumping exercises  need to be developed to help train skating jumpers. As a result of the need for more specific jump training exercises for figure skaters, the investigator developed a jump training program designed specifically to improve jumping ability in loop combination jumps, but It also can be adapted for toe loop jump combinations.  4 STATEMENT OF THE PROBLEM  The purpose of this investigation is to study the effects of a six week training program of depth jumping on jumping ability on arid off the ice.  Subproblemi A subproblem of this investigation is to determine if there is a relationship between vertical jumping ability on the ground and on the ice.  DEFINITIONS  Depth Jump -  a form of jump training which emphasizes an explosive takeoff after landing from a previous jump. Depth jumping is designed to increase reactive ability by training the jumper to make use of temporarily stored potential energy, in the form of elastic recoil.  Reactive Ability - the ability of an athlete while performing multiple jumps, to quickly change from absorbing force to applying force. Plyometric Exercises - exercises or training drills designed to train athletes to use muscle strength to generate the power required in jumping or throwing events. Power Exercises - exercises in which the athlete attempts to produce maximum force in the shortest possible time. Amortization Phase - the braking phase of the jump where negative work is performed to absorb the force of the landing by an eccentric muscle contraction.  Single Loop, Single Loop Combination Jump - a figure skating jump where the skater takes off from a backward outside edge with one revolution (360°), lands on a backward outside edge with the free leg in front, then immediately takes off for another revolution (360°) and landing again on a backward outside edge.  HYPOTHESES  1.  As a result of depth jump training, there is a significant increase in vertical jumping ability on the ground. Rationale: Since performance of the vertical jump requires leg power, an increase in leg power as a result of depth jump training should result in an increase in vertical jump height.  2.  As a result of depth jump training, there is a significant increase in the height of the second jump of a single loop, single loop combination jump. Rationale: Since performance of the skating jump requires leg power, an increase in leg power as a result of depth jump training should result in an increase in skating jump height.  3.  There is a positive linear relationship between vertical jumping ability on the ground and vertical jumping ability on the ice. Rationale: Since leg power is required in the execution of both the vertical jump and the skating jump, these variables should be positively correlated.  6 DELIMITATIONS  1.  The subjects for this study were female figure skaters from Vancouver skating clubs, ranging in age from 1 1 - 1 9 years and had passed the C . F . S . A . Fifth Figure Test and the Silver Free Skating Test or higher.  2.  The effects of the depth jump training were assessed over a six week period.  3.  The effects of the depth jump training were measured by the Sargent Jump Test and a film analysis of a single loop, single loop combination.  LIMITATIONS  1.  The investigator had no control of the subjects' activities outside the testing situation.  2.  Subjects for this study skated a similar number of hours per week but did not have identical skill practice hours.  3.  All subjects did not have the same figure skating coach.  4.  Motivation to produce maximum effort could not be measured in this study.  5.  In the film analysis, the height of the second jump as measured by the relative displacement of the headband was an indication of the height of the jump rather than a true displacement of the center of gravity.  6.  In the film analysis, the accuracy was limited by: the accuracy of the camera speed, the accuracy of the scale factor, and the accuracy of the reduction of film data to actual numerical values.  SIGNIFICANCE OF THE STUDY  The information obtained from this study is valuable to both the athlete and the skating coach. At the present time, there have been no controlled studies done to test the effectiveness of specific conditioning exercises for improving figure skating performance. Many studies have been completed on the effects of various exercise programs, but none have looked at the effects on skating performance. A tested exercise program that proved to be effective in improving skating ability would be a great aid to competitive skaters.  It would also be useful for coaches to know if an  exercise program is not effective in improving skating performance so that alternate methods can be used. Many skating coaches are also interested in the relationship between vertical jumping ability on the ground and vertical jumping ability on the ice. Knowledge of this relationship might assist coaches in assessing the value of the Sargent Jump Test as a predictive measure of jumping ability on ice or as a method of detecting deficiencies.  Chapter 2  REVIEW OF LITERATURE  At the present time, very little information is available on depth jumping.  Depth  jumping is a relatively new form of training designed to increase leg power and the reactive ability of jumpers. Literature on depth jumping which has been translated from Soviet sport literature, is found mainly in track and field and volleyball journals. To the investigator's knowledge, there have been no previous training studies to determine the effects of depth jumping on vertical jumping ability. Therefore, training studies on various other methods of improving vertical jump will be examined.  Studies on Vertical Jump Many training studies on vertical jump have been completed. The average length of the training program in the studies reviewed was six and a half weeks. Weight training was the most commonly tested training method. Isokinetic exercise, isometric exercise, and isotonic exercise using the body weight were other methods used to increase vertical jump. Rope jumping, stair running, repeated jumping exercises and trampoline training were also tested to determine their effects on vertical jumping ability. Staheli, Roundy, and Allsen (1975), Tanner (1971), Darling (1970), Luitjens (1969), Chui (I960), Knudtson (1957), Brown and Riley (1957), Ness and Sharos (1956), Garth (1954) and Capen (1950) found weight training to be an effective method of improving vertical jump. Staheli et a l . (1975) compared the effects of isokinetic and isotonic exercise methods on leg strength, vertical jump, and thigh circumference.  8  9 Subjects were randomly assigned to one of four treatment groups: power rack, leg press, squat, or control. The experimental groups each showed significant improvement in knee and hip extension strength, vertical jump, and. thigh circumference, but no significant differences were found between the training groups on any measure. Tanner (1971) found that deep knee bends using one set of 10 RM and deep knee bends using one set of 50 - 60% RM significantly increased vertical jump, but no significant differences were reported between treatments. The effects of heel raise and deep knee bend exercises on the vertical jumping ability of basketball players were investigated by Darling (1970).  Both types of exercise produced significant gains in the vertical  jump, but no significant difference was found between training exercises. Luitjens (1969) found significant increases in leg strength and explosive leg power using weight training and the Exer-Genie, but no significant differences between the groups.  Chui (1960)  found a significant increase in vertical jump and leg strength in a group of college men as a result of weight training. Similar results were reported by Knudtson (1957) using weight training with a group of female basketball players. The effects of a weight training program on leg strength and vertical jumping ability of basketball players were examined by Brown and Riley (1957).  The training group made significant improve-  ment in leg strength, plantar flexion strength, and vertical jumping ability.  Ness and  Sharos (1956) reported an increase in leg strength and vertical jump as a result of performing deep knee bends and toe raises with weights.  A significant increase in  vertical jumping ability was also found by Garth (1954) in a group of varsity basketball players, following a six week weight training program.  Significant increases in vertical  jump, standing broad jump, and leg strength were observed by Capen (1950) in a group of college men following a twelve week weight training program.  Therefore, there  10 appears to be considerable evidence to support weight training as an effective method of improving leg power as measured by the vertical jump test. Several investigators have reported contradictory evidence regarding the effectiveness of weight training as a method of improving vertical jump. Hansen (1969), Charles (1966), and Roberts (1956) reported that vertical jumping ability did not improve significantly as a result of weight training. Hansen (1969) found that vertical jump did not increase with weight training, trampoline training, or a combination of the two. Charles (1966) found that an explosive weight training program produced significant improvement in leg strength, but not in running speed or explosive power as measured by the vertical jump. Roberts (1956) concluded that a weight training program consisting of forward, lateral, and heel raises, squats, and curls did not significantly improve vertical jump. Exercises using weighted ankle spats were reported to be effective by Fisher (1968) and Anderson (1961) but ineffective by Boyd (1969).  Fisher compared the effects of  weight training, isometrics, Exer-Genie, and jumptrijg with weighted ankle spats on vertical jump. All training methods were shown to be effective in increasing vertical jump but no significant differences were found between the groups.  Boyd (1969) found  that exercises using weighted ankle spats produced significant improvement in vertical jump but there was no significant difference between the control and experimental groups. The effects of weighted ankle spats on jumping performance, agility, and endurance of high school basketball players were studied by Anderson (1961).  The experimental  group significantly increased in vertical jumping ability, agility, and speed of the 300 yard run.  11 Testone (1972) investigated isokinetic training as a method of improving jumping power.  Isokinetic leg extensions were performed on a Super Mini Gym. A significant  increase in strength was reported but no increase in vertical jump. Evidence to support these conclusions was reported by Escutia (1971).  However, Delacerda (1969) found  the Exer-Genie to be an effective method of improving vertical jump but there was no significant difference between the Exer-Genie and a jump rebounding group. The Exer-Genie was also found to be successful in improving vertical jump by Fisher (1968) and Luitjens (1969). The effects of isometric and isotonic training programs on vertical jumping ability were studied by De Venzio (1969).  No significant differences were found among the  groups in back or leg strength, but the isometric group made significant improvement in vertical jumping ability. Tanner (1971) supported De Venzio's results reporting significant improvement in vertical jump, but he concluded from his study that dynamic overload training was more effective than static overloading for improving vertical jump. Fisher (1968) also found isometric training to be effective in improving vertical jump, while Delacerda's findings (1969) failed to support isometric exercise as an effective method of improving vertical jump. The effects of leg strengthening exercises using the body weight on the vertical jumping ability and speed of running of college women were investigated by Blucker (1965).  Results showed that the strengthening exercises had no significant effect on  vertical jumping ability or running speed. Leg strength was not found to be significantly correlated with either vertical jump or running speed. However, Gibson (1961) found an increase in vertical jumping ability in a group of young males as a result of performing various strengthening exercises using the body weight.  12 Rope jumping was another method investigated for effectiveness in improving vertical jump. Marino (1960) found rope jumping to produce significant improvement vertical jump. Fisher (1968) also reported skipping with weighted ankle spats increased vertical jump. Quarles (1967) ran a training program to test the effectiveness of skipping and stair running as methods to improve vertical jump. Quarles found that rope jumping did not improve vertical jump but stair running was effective in improving leg power. Tanner (1971) found repeated maximum vertical jumps to be an effective way of improving vertical jump. Delacerda (1969) also found that jump rebounding exercises produced significant increases in vertical jump. However, Roberts (1956) reported that repeated jumping exercises failed to improve the vertical jumping ability of basketball players, and Escutia (1971) supported these results using a group of volleyball players. Trampoline training was found to be ineffective in improving vertical jump by Hansen (1969) and Brees (1961).  However, Allen (1962) reported that a program of  trampoline training and rope jumping exercises improved hip flexion strength but not hip or knee extension strength.  Summary.  In summary of the literature reviewed, weight training was found to be  an effective method of improving vertical jumping ability (Staheli et a l . , 1975; Tanner, 1971; Darling, 1970; Luitjens, 1969; Chui, 1960; Knudtson, 1958; Brown and Riley, 1957; Ness and Sharos, 1956; Capen, 1950; and Garth, 1954).  Exercises using weighted  ankle spats were also shown to be effective in improving vertical jump (Fisher, 1968; Anderson, 1961).  Isokinetic exercise using the Super Mini Gym was not successful in  improving leg power (Testone, 1972; Escutia, 1971) but isokinetic exercise using the Exer-Genie improved vertical jump (Delacerda, 1969; Luitjens, 1969; Fisher, 1968).  13 Leg strengthening exercises using the body weight were found unsuccessful by Blucker (1965) but successful by Gibson (196T). Rope jumping was found to be effective by Fisher (1968), Marino (1960) but ineffective by Quarles (1967).  Quarles reported  stair running to be an effective method of improving vertical jump. Repeated jumping exercises were found effective by Escutia (1971), Tanner (1971), and Delacerda (1969) but ineffective by Roberts (1956).  Trampoline training was found to be ineffective in  improving leg power by Hansen (1969) and Brees (1961) but effective in improving hip flexion strength (Allen, 1962). Thus, weight training seems to be the most effective method of improving vertical jump.  Depth Jumping Because depth jumping is a very new form of jump training, there is a scarcity of literature on the subject. The literature found in North American sports journals originates from Soviet sport literature. Because of the problems associated with translation, there is not a large volume of information on depth jumping in North American coaching journals. Depth jumping has been done mainly by sprinters, throwers, high jumpers, triple jumpers, and volleyball players. Many volleyball teams and track and field athletes in Canada use depth jumping as a specialized conditioning method. Depth jumping is now gradually being introduced as a jump training method for figure skaters.  Principles of Depth Jumping. Depth jumping is a form of jump training which emphasizes a fast, explosive takeoff after landing from a previous jump.  In performing  a depth jump, the athlete jumps down from an elevated surface such as a box, bench or  14 gymnastic equipment and takes off for a new jump as quickly as possible after landing. "The idea is to jump to the floor and immediately bounce up again in one motion." (Lefroy, 1974). The emphasis is on taking off as quickly as possible in order to train the athlete to use the stretch reflex and elastic recoil to his advantage, thereby training explosiveness.  There are many variations of depth jumps; they can be done  forwards, sideways, backwards, using one leg or two legs. Depth jumping is described as a "shock" method of improving the reactive ability of jumpers (Verhoshanskiy, 1967). Depth jumping is a form of rebound training which is based on making use of the kinetic energy of the braking phase of the jump to create maximum power in the final stages of the takeoff (Wilt et a l . , 1974).  In performing  depth jumps, as in landing from the first jump of a skating jump combination, the angle of knee flexion should be optimal; sufficient to soften the landing yet permit an explosive takeoff (Verhoshanskiy, 1967). Ozolin (1973) states that at the moment of landing from a previous jump, the athlete should absorb or receive the jolt with a slightly bent leg (130° - 135°).  "A greater leg bend does more to increase the landing period and to  cushion the landing than to absorb the shock. " Depth jumping has been described by Wilt (1975) as a form of "plyometric" exercise. Wilt states that reference to plyometric can be found in German and Soviet literature, but is not well known in American sport literature. Plyometric exercises refer to training drills designed to help the athlete utilize his strength to generate the power required to produce the explosive, reactive movement necessary in jumping, throwing, and sprinting (Wilt, 1975). These exercises are based on the principle of prestretching of the muscle in the amortization phase, and to use the kinetic energy  15 developed in this phase in the following contraction (Wilt et a l . , 1974).  Plyometric  exercise is used to train the eccentric aspect of muscle action (Zanon, 1974a). Wilt emphasizes the value of plyometric exercise in attempting to improve the relationship between maximum strength and explosive reactive power.  He states that  many athletes have fantastic strength but are weak in power events such as jumping or throwing.  Plyometric exercise in the form of depth jumps, is recommended for improving  jumping power (Lonskij and Gomberadse, 1975). Zanon (1974a) recommends that in designing plyometric exercises, the braking or the amortization phase should be as short as possible and performed without changing the basic movement pattern.  Timing of the Depth Jump. The objective in performing a depth jump is the optimum timing of the takeoff.  Depth jump training is based on two important physio-  logical concepts: prestretch and elastic recoil of muscle. According to Ozolin (1973) and Boosey (1976), there are three biomechanisms in operation at jump takeoffs: 1) voluntary expression of force, 2) elastic recoil and 3) stretch reflex contraction. These three mechanisms must be combined optimally at the time of the takeoff to produce a good jump. Timing is a critical factor. The takeoff must be timed so that energy stored temporarily in the muscles in the form of elastic energy as a result of prestretch, can have a positive effect on the acceleration of the jump (Wilt, 1975; Asmussen and Bonde-Petersen, 1974; Wilt et a l . , 1974). The jumper must take off quickly after landing of the initial jump to minimize energy loss due to damping.  Research has shown that muscles contract far more forcefully  and efficiently if they are prestretched (Wilt, 1975; Ozolin, 1973). Hockmuth states  16 that the braking of the opposite movement creates positive acceleration power for the original movement, provided that the change takes place smoothly. Several experiments have been conducted to study the ability of muscle to store and re-use energy. Asmussen and Bonde-Petersen (1974a) studied the ability of muscle to absorb and temporarily store mechanical energy in the form of elastic energy for later re-use. Subjects performed maximal vertical jumps on a registering force platform. To vary the energy level of the subject prior to the jump, five different situations were used: from a semi squatting position, with a preparatory counter movement, from a .233 metre platform, from a .404 metre platform, and from a .690 metre platform. Results showed that the height of the jump increased with increasing amounts of energy prior to the jump up to a certain level (.404 metre) and then began to decline. Asmussen and Bonde-Petersen concluded that elastic energy is stored in the active muscles and that the elastic components not only were stretched corresponding to the maximum tension that could be developed voluntarily by the contractile mechanism, but that a certain tension above that was produced temporarily by the rapid stretching of the elastic components by gravity. Asmussen and Bonde-Petersen (1974b) in a subsequent investigation, observed a subject performing various types of work including running, walking, bicycling, and performing knee bends with or without a rebound. Power and steady state metabolic rate were measured under each condition, and the apparent efficiency was calculated. Results showed large variations in apparent efficiency. These variations were explained in accordance with the possibility for re-using the energy absorbed and stored in the muscles as elastic energy during a phase of negative work, in a subsequent phase of  17 positive work.  The condition of this re-using of energy is that the positive phase follows  immediately after the negative phase. This support the extreme importance of timing during a depth jump. Research on single elastic fibers and on isolated frog muscle support the possibility of re-using energy stored in the form of elastic recoil in a subsequent contraction (Cavagna e t a l . , 1968; Carton e t a l . , 1962; Hill, 1950, 1952).  Optimal Height of the Depth Jump. Scientific investigation has shown depth jumping to be an effective method for improving the reactive ability of jumpers (Verhoshanskiy, 1967). Katschajov, Gomberaze, and Revson (1976) studied depth jumps using an apparatus with electrical contacts and a tape attached to the athlete's waist, to measure the height of the rebound, the total time taken for the jump, and the duration of the amortization and takeoff phase.  Experiments on twenty subjects  showed that the highest rebound was achieved after a depth jump from a height of 2'7^" before they began to decrease. At a height of 2'7^", the amortization and takeoff phases were approximately equal, indicating an optimal load.  Katschajov  et a l . concluded that correct height for depth jumps could be established by finding the height where the duration of the amortization and takeoff phases are approximately equal. Verhoshanskiy (1967) states that effective improvement of reactive ability is achieved only when depth jumps are performed from a determined height. Scientific investigation has shown that at a height of 2'5i" maximum speed is achieved in switching the muscles from negative to positive work (Verhoshanskiy, 1967). Verhoshanskiy states that raising the height of the depth jump beyond 3'7g" " . . . materially changes the  18 takeoff mechanism".  The speed of changing the muscles from absorbing force to applying  force is reduced and the depth jump loses its basic advantage.  The optimum height of  the depth jump should be determined by finding the height from which the amortization and takeoff phases are equal as recommended by Katschajov et a l . (1976).  Repetitions for Depth Jump Training. Zanon (1974) recommends five to eight repetitions and six to ten sets of depth jumps performed in a training session with ten to fifteen minutes rest between sets.  Each repetition should be maximal to develop  maximum leg power. To perform jump training exercises maximally, five short work periods, approximately five to fifteen seconds in length, should be separated by up to one minute of rest (Lefroy, 1974). Verhoshanskiy (1967) recommends that depth jumps be done twice a week and a maximum of forty jumps be performed per session.  He suggested that the jumps be  executed in two sets of ten repetitions from a height of 2 5\" y  a height of 3 7\ . X  U  and ten repetitions from  Running and stretching exercises should be done between sets.  Booseyj and Wilt (1974) support the number of repetitions suggested by Verhoshanskiy.  Progression and Overload in Depth Jumping. To create an overload in depth jump training, it is preferable to progress by increasing the height of the jump rather than increasing the number of repetitions or adding additional weight (Verhoshanskiy, 1967; Lefroy, 1974).  It is more condusive to improving leg power to increase the  height of the jump and perform the same number of repetitions rather than to increase the number of repetitions performed at a constant height. should not exceed 3*7^" (Verhoshanskiy, 1967).  The maximum height, however,  19 Lefroy (1974) states:  " . . . quality is more important than quantity and jump  training is done to fatigue rather than exhaustion."  Introduction of Depth Jumping to the Athlete's Training Program.  Depth jumping  is a very strenuous form of training which should be introduced only after basic strength training has been completed. It is a very specialized type of training intended for advanced athletes who have completed preparatory work on squats and squat jumps with weights to develop strength. According to Verhoshanskiy (1966), as an athlete becomes advanced, the effectiveness of weight training decreases. Weight training increases strength, but at the same time it slows down the speed of switching the muscles from yielding to overcoming work. Verhoshanskiy (1966) stated that the ideal training method for jumpers would be one that increased strength and power specifically on jump takeoffs, but would not decrease reactive ability. According to Verhoshanskiy, such conditions can be artificially created if the jumper takes off after a depth jump from a determined height. The dynamic nature and the impact of a depth jump, closely resembles a multiple jump takeoff. Verhoshanskiy (1966) outlines three major stages of strength preparation of athletes. Stage one which he labelled as Class 111 athletes, concentrate mainly on general development of strength. Jump exercises with moderate loading are done, but the emphasis is on all round development.  In stage two, Class 11 athletes work with bar-  bells and weights at 75 - 90% of maximum. Class 1 athletes and Master of Sport.  Stage three of strength preparation involves  He states that the methods are directed mainly to  the development of reactive ability of the neuromuscular junction. He recommends depth  20 jumps from heights of 75 - 100 centimetres. Exercises with near maximum weights are performed to develop explosiveness and to maintain the necessary level of strength preparation. Verhoshanskiy (1966) emphasizes that the development of reactive ability should go through all the stages of strength preparation and that training activities be appropriate to the level of the athlete.  Summary.  Depth jumping is a form of jump training which emphasizes a fast,  explosive takeoff after landing from a previous jump.  It is a type of plyometric  exercise which is designed to improve leg power and reactive ability by landing from a predetermined height and taking off immediately for a second jump. The timing of the takeoff is extremely important, and must be timed so that the jumper can utilize the elastic energy stored temporarily in the muscles due to prestretching. Depth jumping is a very specialized conditioning method designed for advanced athletes, which should be introduced only after basic strength training has been completed. Overload is created in depth jumping by increasing the height of the jump rather than increasing the number of repetitions.  Chapter 3  METHODS AND PROCEDURES  Subjects Thirty female figure skaters from the Vancouver area, volunteered to take part in the study. Two groups were formed: an experimental group randomly selected from volunteers from the North Shore Winter Club and a control group randomly selected from volunteers from various Vancouver skating clubs. The mean ages for the groups were 14.3 years for the experimental and 15.8 years for the control group.  All subjects were  active figure skaters who had passed the Canadian Figure Skating Association Fifth Figure Test and the Silver Free Skating Test or higher. All subjects were practising for Canadian Figure Skating Association tests and/or competitions and skated a similar number of hours per week.  Time and Duration of the Study The study was conducted over a six week period, from the beginning of October to mid November, 1976. The depth jump training was additional exercise for the experimental group and did not replace a regular exercise program. The control group participated in their regular training programs but did not participate in the depth jump program. The regular training programs were varied, consisting of activities such as circuit training, weight training, jogging, and interval running. Training sessions for the experimental group were held twice a week for the first three weeks of the study and three times a week for the last three weeks of the study. Group A skaters attended training sessions Wednesday and Sunday for the first three weeks 21  22 and Monday, Wednesday, Sunday for the last three weeks.  Group B skaters attended  training sessions Monday and Friday for the first three weeks and Monday, Wednesday, Friday for the last three weeks.  The same groupings used by the skating club for  scheduling ice time were used for the jump training schedule so that depth jumping was performed after skating practice throughout the study. There were a total of sixteen training sessions in the study.  Personnel Several graduate students were trained to assist the investigator on testing days.  TESTS  Three testing sessions were held: pretest, at the beginning of the study; midtest, at the end of the third week; and posttest, at the end of the study. All subjects were measured on the Sargent Jump Test and filmed on the ice performing a skating jump combination. Skaters were weighed and measured for height at the pre and post testing sessions. Prior to the pretesting session, subjects attended a familiarization session where they received instructions and demonstrations of the tests and were permitted to practise.  Sargent Jump Test The subject stood sideways with her shoulder within six inches of the wall, feet flat on the floor and reached as high as possible with the arm closest to the wall. The reaching height was marked by the chalked middle finger of the extended arm. The subject then jumped vertically as high as possible and touched the wall with his chalked  23 middle finger. quarter inch.  The distance between the two chalk marks was measured to the nearest Each subject had three trials and the best score was recorded.  Film Analysis Skaters were filmed performing a single loop, single loop combination jump. The technique for this combination was relatively simple and was "over learned" by skaters of this level.  The selection of a simple combination should minimize the effect of  technique improvement. A Bolex 16mm camera was used for filming. Kodak 16mm Tri-X-Reversal 160 ASA (Type 7278) film was used at a speed of 64 frames per second. Two 150 watt flood lamps were used to illuminate the testing area. While performing the jump, the skater was approximately thirty feet from the camera. Three practise jumps were performed in the testing area prior to filming. Three trials per skater were filmed and the trial with the highest second jump was used in further statistical analysis.  Skaters were clothed in light coloured leotards and tights and wore a  white headband.  Data Reduction.  Films were analyzed on the Vanguard Motion Analyzer. Before  beginning the film analysis for this study, a reliability of .99 was established by the investigator for consistency in film measurement.  Height of the second jump was  determined by measuring the vertical displacement of the white headband from the moment of takeoff to the peak height of the jump. This relative displacement of the headband is an indication of the height of the jump rather than the displacement of the center of gravity which is a pure function of the jump.  With knowledge of film frame speed, the time in contact with the ice between the jumps was determined from the frame where the blade first contacted the ice on the landing to the frame where the blade last contacted the ice before takeoff.  Scale Factor. A scale factor was obtained by measuring the length of the skate blade which is a known length, at the frame where the blade was perpendicular to the camera. A scale factor was calculated for each trial of each skater since the distance between the skater and the camera was not constant.  PROCEDURES FOR THE DEPTH JUMP TRAINI N G PROGRAM  The procedures for the program were established from preliminary work to determine the heights and the number of repetitions. Film analysis of figure skating jumps by the investigator showed that the heights recommended by Verhoshanskiy are excessively high for female figure skaters.  In the single loop, single loop combination jump, it was  found that most skaters land from a height of approximately nine inches. The heights and number of repetitions for the program were therefore developed through experimentation with skaters, prior to the study. The depth jump program consisted of two preparatory exercises and five training exercises which were performed on two legs, the left leg only, and the right leg only. The number of repetitions for each exercise remained constant throughout the study with an overload created by increasing the height of the boxes.  After every four training  sessions, the height of the box was increased according to the schedule in Table 1.  25 Table 1 Depth Jump Height  Training Session  Height of Depth Jump  1-4  12"  5-8  15"  9-12  18"  13-16  21"  Table 2 presents an outline of each training session. Table 2 Outline of the Depth Jump Program  Exercise  Total  §  of Sets Preparatory Exercise 1  Total  of Reps./Set  3  10  3  io  3  5  n  3  5  #3  3  5  H  3  5  *5  2  10  #  n Depth Jump Exercise 1 #  §  When performing depth jumps the subjects were reminded of the following principles (Lefroy, 1974): 1.  Each jump should be a maximal effort rather than a submaximal effort.  2.  Each set of jumps should be done quickly with no hesitation between the jumps  3.  The emphasis should be on immediate takeoff when landing from a box so that the skater learns to utilize the elastic recoil of the muscles.  Warm Up Exercises Before starting the training exercises, skaters performed stretching exercises, trunk rotations, ankle rotations, half squats, stride jumps, and various jumping drills  Preparatory Jumping Exercises Using A 6" Box The following depth jumps were done as a transitional phase from the floor to the training height.  Preparatory Exercise *1. The skater jumped down backwards from the box and immediately jumped back onto the box. a)  10 repetitions on two legs  b)  10 repetitions on the left leg only  c)  10 repetitions on the right leg only  Preparatory Exercise *2. The skater stood sideways on the box, jumped down and immediately jumped back onto the box. a)  10 repetitions on two legs  b)  10 repetitions on the left leg only  c)  10 repetitions on the right leg only  Depth Jump Exercises The following five exercises were performed as the main part of the program as outlined in Table 2.  Depth Jump Exercise 1 . #  Using a series of three boxes of equal height, the  skater stood forwards, jumped onto the first box, landed between the boxes, jumped onto the second box, landed between the boxes and jumped onto the third box. a)  5 repetitions on two legs  b)  5 repetitions on the left leg only  c)  5 repetitions on the right leg only  Depth jump exercise *1 was not done sideways nor backwards because of the high skill level required and the safety factor. Single leg jumping was not done on the 21" box, only double leg work. The single leg work was done on the 18" box for training sessions 13 to 16.  Depth Jump Exercise ^2. The skater stood backward on the box, jumped down landing backwards and immediately jumped back onto the box. a)  5 repetitions on two legs  b)  5 repetitions on the left leg only  c)  5 repetitions on the right leg only  Single leg work was not done on the 21" box. 18" box for training sessions 13 to 16.  Single leg work was done on the  28 Depth Jump Exercise 3 . #  The skater stood sideways on the box, jumped down  landing sideways and immediately jumped back onto the box. a)  5 repetitions on two legs  b)  5 repetitions on the left leg only  c)  5 repetitions on the right leg only  Depth jump exercise #3 was not performed from a forward takeoff because of the danger involved in jumping backwards onto the box.  Depth Jump Exercise 4 . #  The skater stood backwards on the box, jumped down  and immediately performed a maximum vertical jump. The skater attempted to get her head over a line marked on a mirror. This target helped to motivate subjects. a)  5 repetitions on two legs  b)  5 repetitions on the left leg only  c)  5 repetitions on the right leg only  Depth Jump Exercise 5 . #  The skater stood backwards on the box, jumped down  backwards and immediately took off for a single loop jump. This exercise attempted to simulate the landing of the first jump and the takeoff for the second jump in a single loop, single loop combination jump. This exercise was done on the leg used in performing the loop combination jump on the ice. Two sets of five repetitions were performed. Skaters worked with a partner for exercises 2, 3, 4, and 5.  One partner  stabilized the box while the other partner performed the depth jumps. The partners changed positions after each exercise, so that there was a short recovery period between each exercise. Each training session was approximately twenty-five minutes in length.  29 EXPERIMENTAL DESIGN  This study used a 2 x 2 factorial design with repeated measures on the second factor (Figure 1). The independent variables were the treatment factor with two levels (Experimental, Control) and the time factor with two levels (Pre, Post).  Three dependent  variables were measured: vertical jump height, skating jump height, and time in contact with the ice. \ j  Figure 1 Groups  '  Pre  Post  Experimental S 1  14 Control S 16  27 Experimental Design  STATISTICAL TREATMENT  A 2 x 2 multivariate analysis of variance with repeated measures on the second factor was performed on the three dependent variables using the program MULTIVAR (Finn, 1968). A transformation matrix on the time factor reduced the pre and post test scores to a difference score for each of the dependent variables. was tested at an alpha level of .05.  Each hypothesis  30 The Pearson Product Moment Correlation was used to determine the magnitude of the linear relationship between vertical jump and height of the skating jump. The correlation was calculated on the pretest data and the posttest data using the program UBC SIMCORT (Le, 1974). The correlation coefficients obtained were tested at the .05 level of significance to determine if they were significantly different from zero.  Chapter 4  RESULTS AND DISCUSSION  Thirty subjects volunteered to take part in this study and were pretested on the Sargent Jump Test and filmed on the ice performing a skating jump combination. After the third training session, one subject from the experimental group withdrew from the study due to a skating injury. For two control subjects, pre and midtest data was obtained but posttest data was incomplete due to skating injuries sustained. Therefore these two controls were eliminated from the study. The effects of the depth jump training program were assessed on a sample of twenty-seven subjects.  The pretest and the posttest correlations also included twenty-  seven subjects. Subject data is summarized in Table 3. Table 3 Subject Data  Group  Age (yrs.) X S.D.  Hejght (cm) X S.D.  Weight (kg) X S.D.  Experimental  14.3  2.1  155.4 9.7  48.1  6.0  Control  15.6  1.6  160.8  6.4  54.0  8.5  E. and C.  14.9 2.0  157.9  8.5  60.0  7.7  31  32 The results of this investigation and the discussion of the results are divided into sections relating to the hypotheses. The first section deals with the effect of the depth jump training on vertical jump and skating jump height; the second section deals with the relationship between vertical jumping ability on and off the ice.  Results: The Effect of Depth Jump Training on Vertical Jump and Skating Jump The following results pertain to the major problem of this investigation: to study the effects of a six week training program of depth jumping on jumping ability on and off the ice. The observed cell means for the experimental and control groups for vertical jump, skating jump, and contact time at the pre, mid, and posttest are presented in Table 4.  Table 5 shows the improvement scores over the six week period In vertical  jump and skating jump while Figure 2 Illustrates graphically the improvement in vertical jump. Table 4 Observed Cell Means  Group  Dependent Variable  Pre  Mid  Post  Experimental  V . J . (in.) S.J. (in.) Time (sec.)  17.14 8.84 .43  18.36 — —  19.01 11.14 .42  Control  V . J . (in.) S.J. (in.) Time (sec.)  18.42 9.50 .45  18.66 — —  18.59 9.55 .45  33  Table 5 Improvement Scores  Dep. Variable  Group  Mean  Vertical Jump  Experimental  1.87  .89  +.5  -+3.0  .17  1.09  -2.0  -+2.0  Ex. and C.  1.04  1.30  Experimental  2.30  1.80  .05  2.52  1.21  2.42  Control  Skating Jump  Control Ex. and C.  S.D.  Range  —  +.4  -+6.8  -4.5 - +5.4 —  34  Figure 2  20 Experimental Control 19 x O  LU X D_  18  H  < u  i—  LU >  17 4  16 4 Pretest  Midtest TIME  The Improvement Trend in Vertical Jump Over the Six Weeks  Posttest  35 The multivariate F (F=6.82, P=.0019) showed that the experimental jump training group showed significantly greater improvement than the control group in height of the vertical jump and height of the second loop jump. The multivariate F also included contact time between the jumps, a dependent variable not included in the hypotheses but important for the interpretation of the results. Table 6 represents the F values for the multivariate analysis of variance and the univariate analysis of variance. Table 6 F Values F-Ratio for Multivariate Test of Equality of Mean Vectors = 6.82 D.F. = 3 and 23  Dependent Variable  Hypothesis Mean Square  P = .00019  Univariate F  P  Step Down F  P  V.J.-Dif.  19.53  20.03  .0002  20.03  .0002  S.J.-Dif.  33.79  7.13  .0132  1.15  .2948  Time-Dif.  0.00  0.61  .4409  0.02  .8763  Observation of Table 6 reveals that vertical jump difference has a highly significant univariate F indicating that the experimental group made significantly greater improvement in vertical jump height compared to the control group. Skating jump difference also has a significant univariate F indicating that the experimental group made significant improvement in skating jump height over the six weeks. However, the univariate F for skating jump difference was of a lower magnitude  36 than the univariate F for vertical jump difference. The step down F is non significant for skating jump difference. When accounting for the difference in vertical jump gains, there is no significant difference between the experimental and control groups on skating jump height. Contact time difference has a non significant univariate F showing that there was no significant difference between the groups.  Also no change in contact time was  noted for either group over the six weeks since this value was not significantly different from zero.  The non significant step down F indicates that time difference did not have  a significant effect on the multivariate F.  Hypotheses.  The first hypothesis states that as a result of depth jump training,  there is a significant increase in vertical jumping ability on the ground.  This hypothesis  was supported since a significant difference was found between the experimental and the control group on vertical jump at the .01 level of significance (Univariate F=20.03, P=.0002). The second hypothesis states that as a result of depth jump training, there is a significant increase in the height of the second jump of a single loop, single loop combination jump. This hypothesis was supported since a significant difference was found between the groups on the height of the second jump at the .05 level of significance (Univariate F=7.13, P=.0132).  Discussion Because depth jumping was effective in improving jumping ability on and off the ice, it is important to consider the factors underlying the increase.  37 For a jump to increase in height, a greater vertical impulse must have been imparted prior to takeoff while in contact with the ice. Impulse, the product of force and time, can be increased by increasing force, time, or both variables.  In this study,  time in contact with the ice was measured from knowledge of film frame speed; however, variation in the magnitude of force during the contact time could not be measured since methods of measuring impulse on ice do not exist under current technology.  The results  of the analysis of variance (Table 6) show a non significant univariate F for the dependent variable contact time difference (F<1, P=.44). There was neither a significant difference between the groups nor a significant decrease in time in contact with the ice over the six weeks. Since time remained constant, the force applied at takeoff must have increased due to a greater muscle strength (force) developed. Increased vertical impulse developed while in contact with the ice, also results in increased vertical takeoff velocity (Ft = mv), providing that the takeoff angle is the same.  If there is a greater takeoff  velocity, power output must have also increased (Power = Fv). Therefore, the increased jump height was due to increased vertical impulse and increased power. The results of this investigation support those of Verhoshanskiy (1966, 1967, 1974) who stated that depth jumping is an effective method of improving leg power. The validity of this statement is supported by the findings of this study, since increased jump height resulted from increased power and vertical impulse.  Results are also in  agreement with Wilt (1974) and Zanon (1974) who described depth jumping as a plyometric exercise, a method of training athletes to use muscle strength to generate the  38 power required in jumping events. Multivariate analysis of variance revealed that jump height on the ground and on the ice increased as a result of improved leg power as measured by the Sargent Jump Test. The non significant step down F for skating jump difference (Step down F=l .15, P=.29) shows that the experimental and control groups are not significantly different in skating jump when the effect of vertical jump improvement is partialled out. This can be interpreted as a non significant influence of technique improvement on improvement in skating jump height. The multivariate analysis indicates that improved jumping ability on the ground and on the ice was primarily due to increased leg power with technique improvement having a minimal effect. Although there is no statistical evidence to support technique improvement as a source of improvement in skating jump height, the investigator feels that depth jump training could have caused some technique improvement. The fact that there is no statistical support for technique improvement as a factor in improvement of skating jump height could be attributed to the fact that minor changes in technique produce more of a qualitative change in jumping ability than a quantitative change. A major change in technique improvement would definitely cause an increase in jump height and would therefore have statistical support. A minor change in technique may not affect jump height significantly yet it may improve the quality of the technique in the execution of the jump combination. Because skating judges consider the technique of the jumps as well as the height of the jumps in the jump combination, an improvement as a result of depth jump training, in the control or the technique even if it does not significantly increase jump height, is nonetheless a valuable contribution to performance.  39 Minor changes in technique were observed by the investigator in the experimental group at the depth jump training sessions as well as in the posttest films.  Practising the  connective section of the jump combination in depth jump exercise *5 could have improved technique by checking of the arms and shoulders on the landing of the first jump, landing from the first jump on the correct spot of the blade (foot), landing from the first jump with optimum knee flexion, and increased plantar flexion at the takeoff of the second jump. It is also possible that the timing of the takeoff for the second jump could have improved by changing the muscles from absorbing force to applying force in one continuous motion. This would help jump height by adding energy in the form of elastic recoil (Boosey, 1976; Wilt et a l . , 1974; Asmussen and Bonde-Petersen, 1974; Zanon, 1974; Hockmuth; Ozolin, 1973; Verhoshanskiy, 1966, 1967, 1974). If the landing of the first jump was more stable due to any of the above factors, a skater could make better use of his available muscle force.  Summary. In summary, improvement in both skating jump height and vertical jump height resulted mainly from an increase in leg power. Technique improvement could have had a minimal effect on the improvement of the skating jump height and the vertical jump height but it is not statistically significant.  Results: The Relationship Between Jumping Ability On and Off the Ice The following results pertain to the subproblem of this investigation: to determine if there is a relationship between vertical jumping ability on the ground and vertical jumping ability on the ice. The pretest correlation coefficients are presented in Table 7 and the posttest correlation coefficients are presented in Table 8.  Table 7 Pretest Correlation Coefficients  Variables  r  Experimental r  Control r  S.J, Best and V . J .  .36*  .50*  .16  S.J. #1  and V . J .  .28  .29  .13  S.J. #2  and V . J .  .52**  .57*  .51*  S.J. #3  and V . J .  .29  .47  .03  Table 8 Posttest Correlation Coefficients  Variables  r  Experimental r  Control r  S.J. Best and V . J .  .49**  .41  .57*  S.J. #1  and V . J .  .45**  .32  .33  n  and V . J .  .42*  .47*  .43  S.J. #3  and V . J .  .35  .28 -  .57*  S.J.  * Significant at the .05 level. * Significant at the .01 level.  41 Hypothesis.  The third hypothesis states that there is a positive linear relationship  between vertical jumping ability on the ground and vertical jumping ability on the ice. This hypothesis was supported by the pretest data (r = .36) and the posttest data (r = .49).  The pretest correlation was significant at the .05 level and the posttest  correlation at the .01 level of significance.  Discussion These correlations indicate that jumping ability on the ground is significantly related to jumping ability on the ice; those skaters who jumped best on the ground also jumped best on the ice. The coefficients of determination were . 13 for the pretest and .24 for the posttest.  Only 13% (pre) and 24% (post) of the variance of the one variable  is predictable from the variance of the other variable, with 87% (pre) and 76% (post) of the variance being left unexplained. Since vertical jump and skating jump are both related to leg power this would account for the positive linear relationship between the variables.  The relatively small magnitude of the correlation is probably due to the fact  that skill is a much larger factor in the performance of the skating jump in comparison to vertical jump performance. Prediction of skating jump height from knowledge of Sargent Jump Score is better than chance but predictions cannot be made with accuracy due to the skill factor involved in skating.  Correlation of the Gain Scores.  The amount of improvement in vertical jump over  the six weeks was significantly correlated with the amount of improvement in skating jump for the experimental and control groups combined (r = .50).  For the experimental group,  a correlation of - .08 was found and a correlation of .59 was found for the control group.  42 The correlation of the gain scores was also calculated (r = .38) for the experimental group excluding subject *4 whose score (6.8|") showed a large deviation from the mean (2.30") on improvement in skating jump. The correlation coefficient between the gain scores was significant at the .05 level for the control but not for the experimental group. Because of the significant correlation between vertical jumping ability on the ground and on the ice, one would expect to find positively correlated gain scores as well.  Improvement in vertical jump should also result in improvement in skating jump.  The gain score correlation (r = .59) for the control group indicates that improvements in vertical jump were accompanied by improvements in skating jump. However, the non significant gain score correlation for the experimental group (r = -.08, r = .38 excluding subject *4) indicates that improvement in one variable is not significantly related to improvement in the other variable. All members of the training group improved in both vertical jump and skating jump but the amount of improvement in the one variable was not accompanied by an equal increase in the other variable, indicating the absence of a relationship between the gain scores. Examination of the factors which affect improvement in these variables will help interpret this apparent discrepancy. Because leg power is involved in the execution of both the vertical jump and the skating jump, one would hypothesize a higher correlation between the improvement scores on the two variables than the one obtained. However, skill and technique are much larger factors in the performance of the skating jump as compared to the Sargent Jump. The Sargent Jump involves mainly leg power, with technique being a minimal factor. The skating jump requires leg power as well as  43 considerable technique. The loop, loop combination jump was selected for this study to reduce the effect of technique Improvement but the technique factor could not be eliminated entirely. It should be noted that technique improvement was only a minor factor in improvement in skating jump height as shown by the non significant step down F for skating jump, but technique effects were not completely removed (Step down F = 1.15).  If technique is removed and leg power is the only factor, gains in vertical  jump should be accompanied by similar gains in skating jump.  Comparison of Pre and Post Correlation Coefficients Between Vertical Jump and Skating Jump. The correlation between jumping ability on the ground and on the ice was .36 at the pretest and .49 at the posttest.  Breaking down these correlations into  separate coefficients for experimental and control groups, the correlation for the experimental group decreased from .50 at the pretest to .41 at the posttest. The correlation for the control group increased from . 16 at the pretest to .57 at the posttest. The correlation coefficient for the experimental group at the pretest indicates that those who jumped best on the ground also jumped best on the ice. This was true of the posttest as well but not to the same degree. After the depth jump training program, those who jumped best on the ground also jumped best on the ice but the correlation was not significant as before training. The homogeneity of the group could have influenced stability of the correlation coefficients. In a homogeneous group, subjects can change their relative rank orders easily, making it more difficult to establish high reliability. It appears that some skaters in the experimental group increased vertical jump more than skating jump while others increased skating jump more than vertical jump  44 (Table 5). The gain score correlation coefficient for the experimental group showed that the gains did not occur consistently together.  It appears that a skater can increase  vertical jump without a corresponding increase in skating jump. Although leg power may have increased, the skater may not have learned to use this leg power effectively on the ice over the course of this study.  Frequently, when leg power or another  component of a skill changes, there is a temporary loss of skill as the skater learns to make fine adjustments in his technique to accommodate these changes.  Some skaters  however, had larger increases in skating jump height compared to vertical jump height. It is possible that these skaters quickly learned to use the increase in leg power to their advantage. The correlation between jumping ability on the ground and on the ice increased from pre to post for the control group (. 16, .57).  At the pretest those who jumped  highest on the ground did not jump highest on the ice; however, at the posttest those who jumped highest on the ground also jumped highest on the ice. Again, the homo-  1  geneity of the group could have caused these correlations to lack stability.  Implications For Skating Coaches Sargent Jump Test. Referring to Tables 7 and 8, the correlation between jumping ability on the ground and on the ice was found to be significant but predictive value is minimal (p- = .13, pre; r^ = .23, post).  The value of the Sargent Jump Test in fitness  testing batteries for skaters, therefore, should be examined. Clearly, Sargent Jump Score cannot be used to accurately predict jumping ability on the ice because of the complexity of the skills in figure skating.  However, it can be useful to the coach as  a means of detecting deficiencies or assessing jumping potential.  45 A poor score on the vertical jump test for a skater who jumps well on the Ice, suggests a deficiency in leg power. A conditioning program to improve leg power should be used to help improve performance. A high score on the vertical jump test for a skater who is a poor jumper on the ice suggests that the skater has potential in terms of leg power, but has not learned to use this leg power effectively on the ice. This could be due to lack of skill, poor technique, a failure to concentrate on explosive takeoffs, or psychological factors.  Depth Jump Training. Depth jumping is an appropriate method of training skaters for jump combinations for several reasons.  The specificity of depth jump training  allows strength or power gains to be developed as required in the skating skill. The force of gravity acting on the skater while performing a depth jump, places a stress on the leg that will induce strength changes.  The major advantage is that the training  effect is introduced as it is needed in the skating skill. Another advantage of the depth jump training program is that it is condusive to learning the positioning of the landing to permit immediate takeoff for the second jump. Timing can be improved by emphasizing the connective section of the combination. The depth jump training program breaks the skill down, isolating the connective section to allow additional practice on the most difficult part of the skill.  Isolation of the  connective section is difficult to accomplish on ice, but can be done on the ground effectively through depth jump training. Depth jumping is specific to skating but is only supplementary to skating practice. The main advantage of depth jumping in comparison to other forms of jump training is that some technique improvement can occur along with strength and power improvement.  46 By modifying depth jump exercise 5 , the investigator feels that the depth jump y  program could also be used to train skaters for toe loop combinations.  In the modified  exercise, depth jump #6, the skater jumps down backwards from the box, lands on one leg with the free leg back (picking foot) and immediately takes off for a toe loop jump. By adding this exercise, the program can be used to train skaters for both loop and toe loop combinations.  Since loop or toe loop jumps are the only jumps that can be combined  with the prescribed double jumps outlined in the three groups of elements for the short program, depth jump training can therefore be used to train skaters for all combination jumps.  Chapter 5  SUMMARY AND CONCLUSIONS  Leg power is an extremely important requirement in skating Jumping. To be a successful jumper, a skater needs the physical ability, leg power, plus the motor skills to execute a balanced, well coordinated, and controlled jump. Deficiencies in either of these areas will impair jumping ability. The major aim of any conditioning program is to reduce the limiting factors in skill performance. If a skater is deficient in leg power, he will be a poor jumper regardless of his skill level. Therefore supplementary leg power exercises are needed in addition to skill practice on the ice to produce maximum performance. Depth jump training is a jump training technique where the athlete jumps down from an elevated surface and immediately takes off for a second jump upon contact with the floor.  It is designed to improve the reactive ability of the jumper when landing  from a previous jump. Depth jump training appears to be an effective method to train skating jumpers for multiple jump combinations. With the increasing emphasis on jump combinations in free skating, it is extremely important to utilize training exercises designed specifically for multiple jumps in skating. The purpose of this investigation was to study the effects of a six week training program of depth jumping on the vertical jumping ability of figure skaters on the ground and on the ice. A subproblem of this investigation was to determine if there is a relationship between jumping ability on and off the ice.  47  48 Thirty female figure skaters volunteered to take part in the study but this number was.reduced to twenty-seven due to skating injuries. All skaters had passed the Canadian Figure Skating Association (C.F.S.A.) Fifth Figure Test and the Silver Free Skating Test or higher and were practising for C . F . S . A . tests and/or competitions. The experimental group consisted of fourteen subjects randomly selected from the volunteers from the North Shore Winter Club, while the control group consisted of thirteen skaters randomly selected from the volunteers from various Vancouver skating clubs.  The experimentalgroup participated in a six week depth jump training program  consisting of two preparatory depth jump exercises and five depth jump training exercises. A total of twenty-seven subjects were involved In the depth jumping study. Subjects were tested at the beginning of the study, the end of the third week, and the end of the study on the Sargent Jump Test and were pre and posttested on the single loop, single loop combination jump by means of cinematography.  The Vanguard  Motion Analyzer was used to determine the height of the skating jump. This study was a 2 x 2 factorial design with repeated measures on the second factor.  The independent variables were the treatment factor with two levels and the  time factor with two levels. Three dependent variables were measured: vertical jump height, skating jump height, and time in contact with the ice. Results of the multivariate analysis of variance showed that the six week depth jumping program was effective in improving jumping ability both on and off the ice. A significant but relatively small correlation was found between vertical jumping ability on and off the ice, using the Pearson Product Moment Correlation.  49 CONCLUSIONS  The following conclusions seem valid based on the findings of this study: A six week depth jumping program is an effective method of improving leg power as measured by the Sargent Jump Test. A six week depth jumping program is an effective method of improving height of the second jump of a single loop, single loop combination jump. There is a low but significant correlation between vertical jumping ability on the ground and height of the second jump in a single loop, single loop combination jump.  REFERENCES  50  51 Allen, D.J. 1962. A Comparison of the Effect of Trampoline Exercises and Jump Rope Activity on the Strength of the Hip, Knee, and Ankle Muscles. Unpublished M.S. Thesis, University of Washington. Anderson, K.A. 1961. The Effect of the Weighted Ankle Spat on the Jumping Performance, Agility, and Endurance of High School Basketball Players. Unpublished M.S. Thesis, University of Wisconsin. Asmussen, E. and F. Bonde-Petersen. 1974. Storage of Elastic Energy in Skeletal Muscles in Man. Acta Physiol. Scand. 91:385-392. 1974. Apparent Efficiency and Storage of Elastic Energy in Human Muscles during Exercise. Acta Physiol. Scand. 92:537-545. Bianchetti-Garbato, S. 1976. Guidance for Judging the Short Program. Publication by the Chairman, I.S.U. Figure Skating Committee. (Mimeographed.) Blucker, J . A . 1965. A Study of the Effects of Leg Strengthening Exercises on the Vertical Jumping and Speed of Running of College Women. Unpublished M.S. Thesis, University of North Carolina. Boosey, D. 1976. Jump Conditioning. Multiple Events. (Mimeographed.)  Canadian National Coach - Jumps and  Brees, C . D . 1961. The Effects of Trampoline Training Upon the Jumping Performance, Agility, Running Speed, and Endurance of High School Basketball Players. Brown, R.J. and D.R. Riley. 1957. Effect of Weight Training on Leg Strength and the Vertical Jump. Unpublished M.S. Thesis, Springfield College. \ Capen, E. 1950. The Effect of Systematic.Weight Training on Power, Strength, and Endurance. Research Quarterly 21:83-93. Carton, R.W., J . Dainauskas, and J.W. Clark. 1962. Elastic Fibers. Jour. Appl. Physiol. 17:547-551.  Elastic Properties of Single  Cavagna, G . A . , B. Dusman, and R. Margaria. 1968. Positive Work Done By a Previously Stretched Muscle. Jour. Appl. Physiol. 24:21-33. Charles, G . L . 1966. The Effects of Selected Explosive Weight Training Exercises Upon Leg Strength, Free Running Speed, and Explosive Power. Unpublished M.S. Thesis, South Dakota State University. Chui, E. 1960. The Effect of a Systematic Weight Training on Athletic Power. Research Quarterly 21:188-194.  52 Darling, D.E. 1970. Comparative Study to Determine the Effect of Heel Raise and Deep Knee Bend Exercises on the Vertical Jump. Unpublished M.S. Thesis, Springfield College. Dedic, J . 1974. Single Figure Skating.  Prague: Olympia.  (I.S.U.)  De Venzio, C.R. 1969. Effects of Two Training Programs on Vertical Jumping Ability. Unpublished M.Ed. Thesis, Pennsylvania State University. Escutia, R.A. 1971. A Comparison of Repeated Jumping and Isokinetic Training For Increasing the Vertical Jump in Volleyball. Unpublished M.S. Thesis, Western Illinois University. Finn, J . D . 1968. Multivariance - Version 4. State University of New York.  Faculty of Educational Studies,  Fisher, S.L. 1968. The Effect of Four Types of Exercise Upon Performance of the Vertical Jump. Unpublished M.S. Thesis, Illinois State University. Garth, R.A. 1954. A Study of the Effect of Weight Training on the Jumping Ability of Basketball Players. Unpublished M.A. Thesis, State University of Iowa. Gibson, D.A. 1961. Effect of Special Training Program for Sprint Starting on Reflex Time, Reaction Time, and Sargent Jump. Unpublished M.S. Thesis, Springfield College. Hansen, R.W. 1969. The Effects of Weight Training and Trampoline Training on Vertical Jumping Ability. Unpublished M.S. Thesis, Illinois State University. H i l l , A . V . 1950. The Series Elastic Component of Muscle. Ser. B 137:273-280. 1953. The Mechanics of Active Muscle.  —RT7TO4-U7.  Proc. Roy. Soc. London,  Proc. Roy. Soc. London, Series B  Hockmuth, G . Biomechanik sportlicher Bewegungen. (Biomechanics of Movement in Sports.) Referred to in Specific Power in Jumping and Throwing. (Wilt et al.) International Skating Union. Regulations 1975. Johnson, B.L. and J . K . Nelson. 1974. Practical Measurements for Evaluation in Physical Education. Minneapolis: Burgess Publishing Co. Katschajov, S.W., K.C. Gomberaze, and A.S. Revson. 1976. Track Technique 65:2084. Translated from Theory and Practises of Physical Culture (U.S.S.R.).  53 Knudtson, P.O. 1957. Study of the Effect of Weight Training and Jumping Exercises on the Jumping Ability of Girl Basketball Players. Unpublished M.A. Thesis, State University of Iowa. Kundrat, V . 1974. Bibmechanicki elementi okreta oko uzduzni ose aparata za kretanje pri izvodenju skokova u umetnickom klizanju. (Biomechanical Elements of the Rotation on the Vertical Axis of the Apparatus for Movement in the Jumps in Figure Skating. Fizicka kultura 28(2):34-36. Translated from Serbo-Croatian by I. and Z. Savor. Le, C. 1974. U.B.C. Center.  S. I.M.C.O.R.T.  Lefroy, C.E. 1974. Jump Training. Technical Jour. 1 (1): 102-103.  University of British Columbia Computing  National Volleyball Coaches Association,  Luitjens, L.L. 1969. Leg Strength and Vertical Jump of Basketball Players As Affected by Two Selected Exercise Programs Conducted Throughout the Competitive Season. Unpublished M.S. Thesis, South Dakota State University. Marino, F.P. 1959. Relationship of Foot Extension Strength and Jumping Exercises to Vertical Jumping Performance. Unpublished M.S. Thesis, Pennsylvania State University. May, H. 1976. Canadian Skating in the Light of the World Championships 1976 at Goeteborg. Professional Circle. Publication of the Professional Skating Association of Canada 11 (2): 10, 15. Ness, P.E. and C . L . Sharos. 1956. The Effect of Weight Training on Leg Strength and the Vertical Jump. Unpublished M.S. Thesis, Springfield College. Ozolin, N. 1973. The High Jump Takeoff Mechanism. Track Technique 52:1668-1671.  Translated by G . Williams,  Quarles, J . N. 1967. A Comparison of Two Training Methods for the Development of Leg Power as Determined by the Results of the Vertical Jump. Unpublished M.S. Thesis, Chadron State College. Roberts, J . A . 1956. A Comparison of the Effectiveness of Two Methods of Training Upon the Jumping Ability of Basketball Players. Unpublished M.A. Thesis, State University of Iowa. Schutz, R.W. and K.D. Coutts. Unpublished Materials.  1974, 1975, 1976. C . F . S . A . Seminar Test Results.  54 Staheli, W., E. Roundy, and P. Allsen. 1975. A Comparison of the Effects of Isokinetic Exercise Methods on Leg Strength, Vertical Jump, and Thigh Circumference. Abstracts, Research Papers 1975 A. A.H.P. E.R. Convention. Tanner, K . J . 1971. A Comparison of Two Methods of Training of the Lower Extremities on Vertical Jump Ability. Unpublished M.S. Thesis, Southern Illinois University. Testone, A. 1972. Isokinetic Training as a Method to Improve the Vertical Jump. Unpublished M.S. Thesis, Western Illinois University. Toyoda, H.  1975. Unpublished data. Japanese Volleyball Association.  Verhoshanskiy, Y. 1966. Perspectives in the Improvement of Speed-Strength Preparation of Jumpers. Track and Field 9:11-12. 1967. Depth Jumping in the Training of Jumpers. Legkaya Athletika Published in Moscow, U.S.S.R. Translated by Yessis Review 3(3):75-78. and G . Chernousov. 1974. Jumps in the Training of the Sprinter. Legkaia Athletika 9:16-17. Translated by Yessis Review 9(3):62-66. Wilt, F., P. Cerutti, S. Embling, T. Toomsalu, J . Pross, F. McGuire, and H. Schubert. 1974. Specific Power in Jumping and Throwing; A Summary of Development in Plyometric Exercises. Mod. Ath. Coach 12(5). 1975. Plyometrics. Athletic Journal. Zanon, S. 1974a. Plyometric fur die Sprunge. (Plyometrics for Jumping.) Die Lehre der Leichtathletik. 16. Translated from German by A. Mahrle. 1974b. Die bewusste Ausnutzung der Muskelvordehnung. (The Advantages of Prestretching.) Die Lehre der Leichtathletik 42:43. Translated from German by A. Mahrle. Zeller, E. 1973. Eiskunstlauf fur Fortgeschrittene. (Figure Skating For The Advanced.) Berlin: Bartels and Wernitz. Translated from German by A. Mahrle.  APPENDICES  55  56 APPENDIX A: Individual Raw Scores Pretest Data Experimental Group  Subject *  Vertical Jump (in.)  Skating Jump *1 Height Time (sec.) On.)  Skating Jump *2 Height Time (sec.) (in.)  Skating Jump *3 Height Time (sec.) (in.)  1  17.0  7.7  .41  9.5  .44  9.8  .45  2  18.0  5.4  .41  7.8  .44  4.9  .38  3  21.0  8.0  .45  11.1  .42  10.0  .47  4  16.5  4.6  .36  4.2  .33  2.9  .36  5  17.0  8.9  .36  9.8  .36  10.9  .36  6  22.0  8.0  .47  10.9  .48  9.7  .47  7  17.5  7.9  .42  7.8  .44  10.5  .36  8  14.5  8.6  .39  8.4  .40  9.4  .47  9  16.5  8.2  .36  7.2  .42  7.9  .40  10  17.5  8.5  .42  8.5  .45  7.9  .45  11  18.0  10.3  .45  10.9  .44  9.3  .48  12  15.0  6.0  .52  3.0  .44  4.6  .47  13  14.5  7.5  .55  10.0  .52  4.6  .47  14  15.0  3.9  .36  4.5  .38  5.2  .45  15  15.0  7.3  .44  8.5  .47  12.8  .38  X  17.14  7.39  .42  8.11  .43  7.69  .43  2.22  1.78  .06  2.61  .05  2.68  .05  S.D.  57 Pretest Data Control Group  Subject #  Vertical Jump (in.)  16  18.5  7.0  .52  8.7  .39  7.0  .52  17  19.0  4.7  .36  5.2  .42  4.1  .52  18  15.0  4.2  .52  5.6  .52  7.6  .55  19  21.5  12.5  .42  13.1  .47  13.0  .48  20  18.5  5.4  .52  ,6.1  .56  4.2  .59  21  20.0  10.8  .45  10.0  .44  12.3  .47  22  16.5  12.4  .42  9.5  .44  11.7  .47  23  18.5  8.5  .45  8.6  .42  7.4  .44  24  20.0  10.6  .44  7.9  .47  6.4  .45  25  18.5  12.8  .42  8.3  .40  12.8  .38  26  16.5  8.6  .41  7.5  .46  9.7  .44  27  17.0  10.6  .47  7.1  .48  8.9  .47  28  20.0  6.4  .42  7.0  .36  4.9  .31  29  21.0  9.9  .41  9.5  .42  9.4  .44  30  18.5  6.3  .39  10.7  .39  6.6  339  X  18.42  9.04  .45  8.05  .45  8.46  .47  1.79  2.78  .05  2.09  .05  3.22  .07  S.D.  Skating Jump 1 Height Time (in.) (sec.) #  Skating Jump 2 Height Time (in.) (sec.) #  Skating Jump 3 Height Time (in.) (sec.) #  Midtest Data Experimental Group  Subject  Vertical Jump (in.)  1  18.7  2  18.0  3  21.0  4  17.0  5  17.0  6  24.5  7  17.7  8  17.5  9  18.2  10  17.2  11  20.0  12  17.0  13  16.0  14  17.0  X  18.36  S.D.  2.19  Midtest Data Control Group  Subject  Vertical Jump (in.)  16  18.5  17  19.0  18  17.2  19  22.2  20  19.0  21  21.0  22  15.0  23  18.5  24  19.7  25  17.5  26  16.7  27  17.0  28  19.5  29  21.0  30  18.5  X  18.66  S.D.  1.96  60 Posttest Data Experimental Group  Subject #  Vertical Jump (in.)  Skating Jump *1 Height Time (sec.) (m.)  Skating Jump 2 Height Time (sec.) On.) #  Skating Jump 3 Height Time (sec.) (in.) #  1  19.0  11.1  .34  12.7  .47  12.4  .38  2  19.0  9.2  i.36  3.9  .40  6.3  .40  3  21.5  12.1  .44  7.8  .44  8.8  .47  4  17.0  6.4  .33  11.4  .33  8.6  .33  5  17.5  10.6  .34  7.6  .45  11.8  .40  6  24.5  11.0  .54  12.8  .56  11.1  .50  7  20.0  6.6  .42  11.1  .38  6.4  .38  8  17.5  13.6  .36  7.3  .44  8.9  .41  9  19.0  10.0  .40  7.1  .44  8.2  .40  10  19.2  10.4  .45  10.3  .45  8.7  .45  11  20.5  11.4  .36  15.1  .36  12.5  .38  12  17.0  7.7  .42  7.3  .40  9.2  .47  13  17.0  10.4  .47  7.3  .45  8.1  .50  4  17.5  6.1  .40  5.9  .34  5.5  .40  19.01  9.76  .40  9.10  .42  9.04  .42  2.12  2.27  .06  3.29  .06  2.22  .05  ]  X S.D.  61 Posttest Data Control Group  Subject  Skating Jump *1 Height Time (in.) (sec.)  #  Vertical Jump (in.)  16  18.5  9.5  .45  4.9  .45  9.0  .48  17  19.5  10.2  .44  10.3  .42  10.6  .47  18  17.0  8.0  .56  6.3  .60  7.7  .63  19  23.0  14.7  .44  13.4  .40  13.1  .45  20  19.5  4.9  .50  4.2  .58  6.3  .55  21  19.5  7.4  .53  12.5  .40  9.0  .38  22  14.5  6.8  .44  7.8  .48  8.2  .44  23  17.7  9.2  .36  9.5  .36  9.4  .38  24  21.0  9.3  .42  8.5  .45  10.7  .44  25  17.5  7.7  .40  8.3  .42  8.3  .40  26  17.0  7.6  .45  9.2  .47  8.2  .42  27  17.0  8.9  .42  9.5  .45  8.7  .42  28  20.0  7.2  .36  6.4  .42  4.8  .31  29  22.5  -  -  -  -  -  -  X  18.59  8.55  .44  8.52  .45  8.75  .44  2.16  2.32  .06  2.69  .07  2.07  .08  S.D.  Skating Jump 2 Height Time (in.) (sec.)  Skating Jump 3 Height Time (in.) (sec.)  #  #  ,  The Amount of Improvement In Vertical Jump and Skating Jump Over the Six Weeks Experimental Group  V . J . (in.)  % Increase  S.J. (in.)  1  2.0  11.8  2.9  29.6  2  1.0  5.6  1.4  18.0  3  0.5  2.4  1.0  9.0  4  0.5  3.0  6.8  67.6  5  0.5  3.0  0.9  8.3  6  2.5  11.4  1.9  17.4  7  2.5  14.3  .6  5.7  8  3.0  20.1  4.2  44.7  9  2.5  15.2  1.8  22.0  10  1.5  8.6  1.9  22.3  11  2.5  13.9  4.2  38.5  12  2.0  13.3  3.2  33.3  13  2.5  17.2  0.4  4.0  14  2.5  16.7  0.9  17.3  X  1.87  2.30  .89  1.80  Subject  S.D.  % Increase  The Amount of Improvement In Vertical Jump and Skating Jump Over the Six Weeks Control Group  % Increase  Subject  V . J . (in})  S.J. (in.)  % Increase  16  0.0  0.0  0.8  9.2  17  .5  2.6  5.4  96.3  18  2.0  13.3  0.4  5.7  19  1.5  7.0  1.6  12.2  20  1.0  5.4  0.2  3.2  21  -  .5  -2.5  0.2  1.6  22  -2.0  -2.1  -4.2  -33.9  23  -  .8  -4.3  2.1  24.4  24  1.0  5.-0  .1  0.9  25  -1.0  -5.4  -4.5  35.2  26  .5  3.0  -0.5  - 5.2  27  0.0  0.0  -1.1  -10.4  28  0.0  0.0  -0.2  2.9  X  .17  .05  S.D.  1.09  2.52  APPENDIX B: Sample Calculations A.  Trial  Actual Blade Length (In.)  Calculation of Scale Factor  Film Blade Length X-Coordinates Ax l 2 1 2 In. x  Scale Factor  1  12.00  4.792  5.310  .518  23.166  2  12.00  1.968  2.484  .516  23.256  3  12.00  3.248  3.733  .485  24.742  Scale Factor = Actual Blade Length Film Blade Length Trial n = 12.00 = 23.166 7518" Trial n = 12.00 = 23.256  "T5T6"  Trial *3 = 12.00 = 24.742 "7485  B. Calculation of Jump Height  Trial  Origin2  Actual Height (in.)  6.107  4.571  8.039  4.930  6.471  4.923  11.140  4.850  6.443  4.855  10.045  #  Scale Factor  Y-Coordinates Origin-j HB  HBj  1  23.166  5.751  4.562  2  23.256  5.999  3  24.742  6.032  2  Trial *1 Headband 1 - Origin 1 = 1.189 (Yj) Headband 2 - Origin 2 = 1.536 (Y ) 2  Height of Jump = AY x Scale Factor = .347 x 23.166 = 8.039 inches Trial *2 Headband 1 - Origin 2 = 1.069 (Y])' Headband 2 - Origin 2 = 1.548 (Y ) 2  .Height of Jump = Y x Scale Factor = .479x 23.256 = 11.140 inches A  Trial  n  Headband 1 - Origin 1 = 1.182 (Y]) Headband 2 - Origin 2 = 1.588 (Y ) 2  Height of Jump = AY x Scale Factor = .406 x 24.742 =10.045  66 APPENDIX C: Computer Program and Output Computation of Jump Height from Film Data The following program was used to compute jump height from the data obtained using the Vanguard Motion Analyzer. The program was written by: B.M. Mason, Department of Civil Engineering University of British Columbia 1976  C C C  L I S T I N G CF COMPUTER F i C G E M TO C ALCUL ATI LENGTH AND t EIGHT CF S K AT I KG JOKES, INTEGES SN,SNI |1G0) , T R I A L , C l SEAL EBX1,E£Y1,HEX2,HBY2,C1 ,02,HT,LEN,A2 (3) ,A3(3) ,A4 (3) ,A1 (3) READ (5,1) NCAIC 1 FORMAT (14) SNI(1) = 0 NCALC1 = NCA1C-H DC 2 I=1,NCAIC1 I F (I•EQ.NC1IC1)GC IC 26 9 HEAD(5,3) SN,IBIAI,BEEN,CI,E11,BL2,HBX1,HBY1,01,HBX2,HBY2,02 3 FCRMAT ( 2 1 3 , F 7 . C , 1 3 , 6 F 8 . 0 , f 7 „ 0, F 9. C) 10 I F ( S N . E Q . SMI (I) ) GC TO 11 I F ( I . E Q . 1 ) G 0 TO 24 26 WRITE (6,14) 14 FORMAT (/20X, ' *****CCMEt3'IEE DATA**'/5X, 'T * ,6X, 'TIME* 1,5X,* SCALE * , 4X , * LENGTH ',4X,* HEIGHT') a RITE (6,15) 15 FORMAT (7X, • (SECONDS) ' , 4 X , » FACTOR , 2X , • (INCHES) »,2X, 1 • (INCHES) •/) DO 13 J=1,.3CCUNT WRITE (6,16) J,A1 (J) , A 2 ( J ) , A3 (J) ,A4 (J) 16 FORMAT ( I 6 , 4 F 1 0 . 3 ) 13 CONTINUE I F ( I . E Q . N C A 1 C 1 ) G O TC 2 GO TO 25 24 8 S I T E (6,23) 23 FORMAT('1') 25 CONTINUE JCOUNT=0 WRITE (6,5) SN 5 FCRMAI (/,76 ('*') //2CX,'SOEJECT NUMBER* , I 5 / 2 0 X , i*«**#g^jj DATA******* * /) BRITI(6,6) 6 F O R M A T ( 5 X , ' I , 3 X , * E t A D E IINGTH•,45,•TIME• , 16X,'X CO-CED* ,12X,'Y CC-OED*) WRITE (6,7) 7 FORMAT ( 7 X * ACTUAL' , * MEASURED FRAMES *,6X,'1 *, 7X, * 2* 1,5X,•BB1',3X,'GRIG 1 *,5X,* HE2•,3X,'GRIG2'/) 11 S N I ( I + 1)=SN BLX = ABS ( B I 1 - E I 2 ) JCCUNI=JCCUN1+1 SCA1E=B1EN/BIX DELY1=AES (HBY1-01) DELY2=A£S (HBY2-C2) DELY=ABS (EEIY 1-DEIY2) DELX = ABS (HEX1-HBX2) HT=DELY*SCAiE LEN=D£LX*SCAIE CT1= FLOAT(CT)/€ 4. A1 (TRIAL)=CT1 A2 (TRIAL) =SCAIE A3 (TRIAL) =IE5*2 A4 (TBIAL) = fil WRITE(6,8)TEIAI,E1EN,BIX,CT,HBX1,EEX2,HBY1,01,HBY2,02 8 FORMAT ( I 6 , E 8 . 2 , F 8 . 3 , 1 6 , 6 F 8 . 3 ) 2 CONTINUE STOP END 1  ,  f  Sample Computations: Pretest 68 ****** *********** **** ******* *********************************************** SOBJECT* NUMBER 1 *****RAW CATS*******  T 1 2 3  EL A EE LENGTH TIME ACTUAL MEAS DEED FRAMES 11.50 1-1.50 11.50  T  TIME (SECONDS)  1 2 3  0.406 0.438 0.453  0.543 0. 561 0.551  26 28 29  X CC-OED 1 2 4.900 5. 217 5,214  6, 093 €.263 6.641  HB1 4.690 4.673 4.743  I CO-OED ORIG1 3.509 3. 505 3.513  H.B2  5, 053 5. 157 5.204  G.RIG2  3.506 3. 507 3.503  *****COMfUTED DATA** SCALE LENGTH HEIGHT EACTGE (INC FES) (INCHES) 21.179 19.7S3 20.671  50.532 41.408 59.566  7.751 9,540 $.830  ***************** ********************************************************** SUBJECT NUMBER 6 *****RAW LATA******* T 1 2 3  BLADE LENGTH TIME ACTUAL MEASURED FEAMES 12.00 12.00 12.00  T  TIME (SECONDS)  1 2 3  0.465 0.484 0.469  0.505 0.453 0.526  30 31 30  X CC-CBD 1 2 7.610 4.9 57 5.559  8. 831 6.274 6.718  HB1 5.287 5.303 5.071  Y CO-OBD OBIG1 . HB2 4. 389 4.380 4.357  5. 625 5.707 5.498  ORIG2  4.389 4,372 4.357  *****CCME0TE£ DATA** SCALE LENGTH HEIGHT FACTOR (INCHES) (INCHES) 23.762 26.490 22.814  58.028 69.775 52.882  8,032 10.914 9,741  *************************************************************************** SUBJECT NUMBEB 11 *****££$ ££<££******* T 1 2 3 T  BLADE LENGTH TIME ACTUAL MEASURED FEAMES 11.50 1 1, 50 11.50 TIME (SECONDS)  0,385 0,414 0.380  29 28 31  X CG-ORD 1 2 6.369 8. 352 2.972  7.146 9. 058 3. 744  *****CCMEUTEE DATA** SCALE LENGTH F; EIGHT FACTOR (INCHES) (INCHES)  1 0.453 29.870 2 C.438 27.778 3 0.484 30.263 EXECUTION TERMINATED  46.418 39.222 46.726  10,335 10.944 9.321  HB1 5,158 5. 219 5.002  ¥ CO-ORD OHIG1 4.437 4,433 4.339  HB2 5,511 5. 612 5. 313  ORIG2  4.444 4, 432 4.342  Sample Computations: Posttest  69  ****************************** SUBJECT NUMEEB 1 *****££{! DATA******* T  BLADE LENGTH TIME ACTUAL MEASOBED FBAflES  1 2 3  11.50 11.50 11.50  T  TIME (SECCNDS)  1 2 3  0.344 0.469 0.375  C, 336 0.218 0.371  - X CO-CRD 1 2  22 30 24  3.020 2,409 3.912  3.759 3.230 4.669  HB1 4.650 4.631 4.659  Y CC-OED ORIG1 . HB2  ORIG2  4.035 4,022 4.025  4.049 4.023 4.029  4.989 4.983 5.064  *****CCMEUTEE DATA** SCALE LENGTH EEIGHT FACTOR (INCHES) (INCHES) 34.226 36.164 30.SS7  50.586 59.380 46.S30  ******************************  4  11.124 12.693 12.430  ********************************************  SUBJECT NUMBER 6 *****£ fljj EAIA ****** * T  EIADE LENGTH TIME ACTUAL MEASURED FRAMES  1 2 3  12.00 12.00 12.00  T  TIME (SECONDS)  1 2 3  0.547 0. 563 0.500  0.383 0.349 0.359  35 36 32  X CO-OED 1 2 6.698 5.773 4.103  7.607 €.366 4.761  HB1 5.831 5.646 5.634  Y CO-OED ORIG1 5.140 4.977 4,974  H.82  OEIG2  6,177 6,007 5.973  5.136 4.966 4.980  *****CCMfUTED DAT A* * SCALE LENGTH EEIGHT FACTOR (INCHES) (INCHES) 31.332 34. 3 84 33.426  44.428 40.779 43.989  10.966 12, 791 11,131  ************************************************ ********* ****************** SUBJECT NUMEEE 11 *****RAH DATA******* T 1 2 3 T  ELA.DE LINGTB TIME ACTUAL MEASCEED FRAMES 11. 50 1 1. 50 11.50 TIME (SECCNDS)  1 2 3 EXECUTION  0. 352 0,376 0.343  23 23 24  X CC-OED 1 2 5. 534 3.388 4.783  6^ 159 4. C89 5,587  *****COMEuTEE DATA** SCALE LEKGT'H EE IGHT FACTOR (INCEES) (INCHES)  0.359 32.670 0.359 3G.585 0.375 33.528 TERMINATED  40,638 42.880 53.S13  11.435 15.140 12.472  HB1 4. 700 4.661 4.611  Y CO-ORD ORIG1 4.003 4. 082 3.970  HB2  ORIG2  5. 040 5. 058 4.976  3,993 3.98 3.963  70 APPENDIX D: Biomechanical Description of Connective Section of the Single Loop, Single Loop Combination Jump The following is a description of a single loop, single loop combination jump executed on the right leg with counterclockwise rotation. The reader is referred to Plate 1, for a frame by frame illustration of the skill. In the single loop, single loop combination jump, the skater should land from the first loop jump with the free leg in front (left leg), the shoulders and arms checked (left arm in front, right arm back), and the skating knee flexed. When the toe of the landing leg (right leg) contacts the ice, the skater continues to flex the knee slightly and then extends the hip, knee, and plantar flexes the ankle of the takeoff leg (R leg). While in contact with the ice between the two jumps, the skater must flex and extend the takeoff leg in one smooth motion so that energy stored in the muscles as a result of prestretching can have a positive effect on jump height. When the leg contacts the ice on the landing of the first jump, the muscles contract eccentrically due to the rapid stretching by gravity and,energy is therefore stored temporarily in muscle. From film analysis of the 171 single loop, single loop combinations in this study, the following points should be emphasized in coaching figure skaters: 1. Timing is extremely important.  In the connective section of the combination,  the skater must change from flexing on the landing of the first jump to extending on the takeoff for the second jump in one continuous motion. If this action is stopped, elastic energy from prestretching is damped and lost in the form of heat. 2.  The average contact time between the jumps in this study was .43 seconds, and did not significantly decrease over the six week period. There is evidence in  the literature that reaction time Is Inherent and cannot be greatly changed. Therefore, the skater should attempt to develop maximum force while in contact with the ice to produce maximum vertical impulse, resulting in a higher jump. In a well executed single loop, single loop combination jump, the landing position of the first jump should be the takeoff position for the second jump.  72  PLATE 1 CONNECTIVE SECTION OF THE LOOP, LOOP COMBINATION JUMP  

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