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Evaluation of a physical activity intervention for new parents: protocol paper for a randomized trial Quinlan, Alison; Rhodes, Ryan E; Beauchamp, Mark R; Symons Downs, Danielle; Warburton, Darren E R; Blanchard, Chris M Nov 9, 2017

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STUDY PROTOCOL Open AccessEvaluation of a physical activityintervention for new parents: protocolpaper for a randomized trialAlison Quinlan1* , Ryan E. Rhodes1, Mark R. Beauchamp2, Danielle Symons Downs3, Darren E. R. Warburton2and Chris M. Blanchard4AbstractBackground: Identifying critical life transitions in people’s physical activity behaviors may illuminate the most opportuneintervention apertures for chronic disease prevention. A substantive evidence base now indicates that parenthood is one ofthese critical transition points for physical activity decline. This study will examine whether a brief theory-based interventioncan prevent a decline in physical activity among new parents over 6 months following intervention. This study protocolrepresents the first dyad-based physical activity initiative in the parenthood literature involving both mothers and fathers;prior research has focused on only mothers or only fathers (albeit limited), and has shown only short-term changes inphysical activity.This study will be investigating whether a theory-based physical activity intervention can maintain or improve moderate tovigorous intensity physical activity measured via accelerometry of new parents over a 6 month period following interventioncompared to a control group.Methods: This study is a 6-month longitudinal randomized controlled trial. Parents are measured at baseline (2 monthspostpartum) with two assessment points at 6 weeks (3.5 months postpartum) and 3 months (5 months postpartum) and afinal follow-up assessment at 6 months (8 months postpartum). The content of the theory-based intervention was derivedfrom the results of our prior longitudinal trial of new parents using an adapted theory of planned behavior framework topredict changes in physical activity.Results: A total of 152 couples have been recruited to date. Sixteen couples dropped out after baseline and a total of 88couples have completed their 6-month measures.Discussion: If the intervention proves successful, couple-based physical activity promotion efforts among parents could be apromising avenue to pursue to help mitigate the declines of physical activity levels during parenthood. These findings couldinform public health materials and practitioners.Trial registration: This trial has been registered with the Clinical Trials Registry maintained by the National Library ofMedicine at the National Institutes of Health on April 19, 2014. The registration ID is NCT02290808.Keywords: New parents, Physical activity, Planning, Self-regulation* Correspondence: alisonq@uvic.ca1Behavioural Medicine Laboratory, University of Victoria, 3800 Finnerty Rd.,Victoria, B.C. V8P-5C2, CanadaFull list of author information is available at the end of the article© The Author(s). 2017 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, andreproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link tothe Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.Quinlan et al. BMC Public Health  (2017) 17:875 DOI 10.1186/s12889-017-4874-7BackgroundThere is convincing evidence that physical activity is associ-ated with numerous health benefits and a reduced risk ofchronic disease and premature mortality [51, 69]. Inaddition to the physical health benefits obtained by physicalactivity, there are also numerous mental health benefits.These include improvements in well-being, reduction ofdepression and anxiety, enhancements of cognitive function-ing and improvements in overall quality of life [8, 24, 45].Despite the vast number of benefits associated with regularphysical activity, the majority of adults do not meet therecommended guidelines of 150 min of moderate tovigorous activity accumulated over the course of a week[16]. Results from the Canadian Health Measures Surveyshowed that adults aged 18-79 yr. accumulated just 12 minper day of moderate-to-vigorous physical activity (MVPA)and that only about 1 in every 5 adults was actuallyachieving the recommendations [16].There is also evidence to suggest that the onset ofparenthood may contribute to a decline in physicalactivity for adults [7, 29, 54]. First-time parents inparticular represent a population who could greatlybenefit from the effects of physical activity due to parent-hood being associated with decreased sleep, increased stress,anxiety and reduced mental well-being [19, 20, 40]. Thus,parents of young children may be an important populationto target given the evident decline in physical activity andimportant roles they play with regard to their children’sphysical activity. Eighty-five percent of Canadians willbecome parents during their lifetime and the mean age forfirst-time parents in Canada is 28.5 yr. [61]. The additionaldemands of parenthood necessitate lifestyle changes and thismay compromise the personal physical activity behaviors ofnew parents [7, 12]. Indeed, in a recent review examininglongitudinal physical activity studies parenthood emerged asa significant predictor of physical activity decline [54]. In atrial examining physical activity trends across non-parents,first-time parents and second time parents, up to 50% ofadults who were regularly active drop their physical activitybehaviors when they become parents and this deficit is stillpresent after 5 years [48]. The effect was shown in bothfathers and mothers, suggesting that both parents experi-ence these declines in their physical activity behaviors,although women appear to have a steeper trajectory inMVPA decline. A study by Mailey and McAuley [34] notedthat mothers have the lowest physical activity self-efficacy(i.e., perceived confidence to be active) of any group theyhave examined, including frail elderly and diseased popula-tions. Clearly, parents represent an important physicalactivity promotion demographic.However, there has been limited research on theeffectiveness of physical activity interventions targetingparents together. The majority of studies examined theimpact of parents’ physical activity on their children’s’physical activity [6], or is focused solely on the physicalactivity of mothers [23], with a few studies focusing onthe physical activity of fathers [39]. In a review onphysical activity interventions for post-natal mothers[23], 20 intervention studies were identified that had aphysical activity promotion component among mothersbetween 4 and 12 weeks after giving birth. Out of theseven studies that focused specifically on improvingphysical activity among inactive moms, six had signifi-cant effects on MVPA. In the meta-analysis portion ofthe review, a moderate effect was found for an increasein frequency of physical activity at post-test suggestingthat interventions to improve physical activity amongpost-natal populations can be an efficacious avenue forphysical activity promotion efforts. Still, no research hasexamined whether intervening on physical activity indual parent households has promise.Despite the limited research targeting parents togetherto improve their physical activity, evidence from otherhealth domains that have intervened at the couple levelhave shown some promise [3, 35]. For example, in arecent review evaluating couple-based interventions,four out of seven were found to be more effective thanregular care [3]. From the literature that has focused onpopulations with chronic conditions, couple-based inter-ventions have been found to be more effective than indi-vidual focused interventions [35]. Furthermore, there isevidence to suggest that couples change their physicalactivity behavior in tandem [48], and therefore targetingthe couple could provide an effective mode for interven-tion to help mitigate the decline in physical activityduring early parenthood.Theoretical frameworkUnderstanding physical activity during parenthood hastypically taken a social cognitive approach, whereattitudes/outcome expectations, perceived norms andperceptions of capability (perceived control/self-efficacy)are considered the antecedents of intention andintention is the key causal agent in behavior [53]. Themost popular applications have included social cognitivetheory [5], theory of planned behavior [1] and the trans-theoretical model of behavior change [41]. Overall, theevidence has not been supportive of attitude or norma-tive changes that can predict physical activity decline inparents with the exception of some associations betweenaffective aspects (e.g., stress relief ) and physical activity[37]. By contrast, a sense of lowered capability – oftenfrom increased child care duties and the struggle tobalance occupational and domestic responsibilities – hasbeen a reliable predictor of physical inactivity in reviewsof parenthood and physical activity research [7, 53]. Self-regulatory constructs (goal setting, planning, self-monitoring) have also shown evidence as explanatoryQuinlan et al. BMC Public Health  (2017) 17:875 Page 2 of 10mediating mechanisms within successful interventionsin new mothers [23]. From a conceptual standpoint,self-regulatory constructs are often viewed as bridgeconstructs between good intentions and behavior[13, 27, 46, 58] and may be useful to augmenttraditional social cognitive approaches such as theoryof planned behavior. The blend of evidence onmotivational aspects such as perceived capability andself-regulatory constructs such as planning and self-monitoring form the theoretical basis for this trial.Pilot researchThis research builds on prior longitudinal assessments ofparenthood and health behaviors [49] as well as our priorrandomized controlled trial examining self-regulatorstrategies and physical activity among parents [52].Our prior research has shown that couples changetheir physical activity behavior and motivation togetherand therefore our intervention targets the couple.Indeed, changes at the level of the couple showedcorrelations between slopes and intercepts of r = .62 forbehavior, and r = .39 to r = .71 [48, 49] for motivationalconstructs which demonstrates considerable symmetryin physical activity between mothers and fathers.Current approaches that target mothers may not be aseffective at sustaining changes in physical activity asincluding both parents. Working with both parents allowsfor workload negotiation, social support and collectivegoals to be managed together. Although we have notlocated any published couple-based physical activity inter-ventions for new parents to date there is evidence in otherhealth domains/populations that couple-based interven-tions are more successful than individual-level interven-tions [9–11]. This study examines whether a couple-basedphysical activity intervention helps to maintain or improvephysical activity among new parents.ObjectivesThe primary research question is whether a theory-based condition (based on an adapted theory of plannedbehavior) can maintain or improve adherence to regularmoderate/vigorous intensity physical activity among newparents when compared to those in the control condi-tion at 6 months post intervention (8 months after thebirth of their first child). We also will explore foursecondary research questions including:1) Does the theory-based condition improve motivational,health-related quality of life, and health-related fitnessoutcomes among new parents when compared to thosein the control condition at 6 months post intervention?2) Can group differences among new parents with regardto these motivational, behavioral, and health-relatedfitness outcomes be explained through a mediationmodel?3) Can motivational variables predict adherence?4) Is there a seasonal, initial physical activity status,mental health or gender difference across primaryoutcomes by assigned condition?HypothesesWe hypothesize that physical activity will be higher forparents in the theory-based condition in comparison toparents in the control condition after controlling forpossible confounds. The effect may wane over time fromthe initial measurement period at 2 months after theonset of parenthood but all outcomes will remain signifi-cantly higher 6 months after intervention. For thesecondary research questions we hypothesize that thetheory-based condition will change salient underlyingmotives (theory of planned behavior constructs, self-regulation constructs) for physical activity because itsbasis is from the key results of our prior longitudinaltrial of new parents [52] and past interventions amongmothers [23]. Health-related physical fitness and qualityof life will also be higher for this condition in compari-son to the control condition. All outcomes will remainsignificantly higher at 6 months post-intervention in thetheory-based condition compared to the standard phys-ical activity education group. Improvements in bothgroups of mothers may occur due to recovery frompregnancy, but our hypotheses should still hold. Thecovariance of the assigned conditions (theory-based,standard) on adherence will be explained by changes inthe salient underlying motives for physical activity (i.e.,manipulation check). In turn, the covariance betweenthese salient underlying motives and health-relatedoutcomes will be explained by physical activityadherence among conditions. The approach will testAjzen’s [1] theory of planned behavior adapted toinclude self-regulatory constructs as a bridge betweengood intentions and behavior [46]. Affective attitude andperceived behavioral control will predict intention,intention will predict self-regulation constructs ofplanning and self-monitoring, and these will predictadherence across conditions. As for seasonal or genderdifferences we hypothesize that there will be no differ-ences, however, this question is exploratory becausethere is limited research at present.MethodsThe trial will follow the consolidated standards ofreporting trials statement [57].Trial designThis study is a two-arm, parallel design, single blindedrandomized controlled trial (RCT). ParticipantsQuinlan et al. BMC Public Health  (2017) 17:875 Page 3 of 10(mothers and fathers) are randomized to one of twogroups 1) physical activity theory-based condition; or 2)standard attention control condition for 6 monthsduration post parenthood onset (baseline assessment at2 months postpartum and final follow-up at 8 monthspostpartum). The trial is registered with the NationalLibrary of Medicine at the National Institutes of Healthand was registered on April 19, 2014. The registrationID is NCT02290808. We obtained ethical approval fromthe University of Victoria Human Research Ethics Boardand all amendments to the study went through theHuman Research Ethics Board.Participants and recruitment procedureParticipants are common law or married couples, whoreside in greater Victoria, British Columbia and who areexpecting or have just had their first child and are over theage of 18 years. Single parents are no doubt an interestinggroup for study with physical activity, but they will beexcluded from this study because the intervention is target-ing the couple. Same sex parents and surrogate parents areincluded in the study if their baby is within four-months ofbirth. Our prior longitudinal studies also included same sexcouples, although this accounted for less than 1% of thesample [52]. Parents are included if they participate in phys-ical activity below or above Canadian recommended guide-lines [62] (i.e., 150 min of moderate or higher intensityactivity per week). While many intervention studies oftenseek to screen out active participants in order to createchange in physical activity, new parents represent a groupwhere 50% who were previously meeting physical activityguidelines, will no longer be active at this level [37]. Ourintervention is focused on both preventing that decline andimproving physical activity. As a result, we are recruitingcouples who are both active or inactive. Participants arescreened for physical activity readiness via the PhysicalActivity Readiness Questionnaire for Everyone (PAR-Q+;www.eparmedx.com) [66, 67]. Those individuals who arenot ready or able to participate in moderate intensity phys-ical activity are excluded for safety reasons. This may includecomplicated pregnancy, caesarean section or any previousinjuries in potential participants. Mental health conditionssuch as depression or anxiety are not contraindications tobeginning a physical activity program [55], and thereforeparticipants are not excluded if they have a mental healthcondition. However, we are measuring psychological distressand mental health among participants and are examiningthe impact this condition may have on retention andprogram success.RecruitmentRecruitment has already started and we are continuingto recruit through several clinical and communityavenues including the utilization of online platforms,print campaigns, in-person recruitment, as well as on areferral basis. Study announcements outlining theresearch are posted to online interest sites, where theyare marketed to the target demographic. Paper advertise-ments are distributed systematically around the city,focusing on doctor’s offices, health centers, midwiferies,recreation centers, maternity and baby stores, and anyother community organizations offering prenatal classesor programming for first-time parents. Potential partici-pants recruited via online or print methods are invitedto contact the project coordinator and research assis-tants associated with this project, who act as the mainpoint of contact. In-person recruitment initiatives takeplace at community fairs targeting new parents such asbaby fairs, health shows, and community markets. Atthese events, brochures outlining the research are dis-tributed. The research assistant is also available to an-swer any questions about the study, as well as to speakto the importance of being physically active postpartum.The research assistant then invites interested attendees toparticipate in the research study. A sign-up sheet isdistributed for those interested in participating (providetheir name, home/cell phone number, email, expected duedate). Lastly, enrolled participants are invited to referother families that may be interested in participating.ProceduresAfter interested participants contact the research assist-ant and are determined to be eligible to participate inthe study, (and provide an approximate date for contact2 months post-baby) we schedule a fitness test at ourlab. At the initial visit to the lab, signed informedconsent is obtained from participants by the projectcoordinator after overviewing the requirements of thestudy. Participants are assigned an identification numberand all data is attached to this number to ensure confi-dentiality. A qualified exercise professional is employedto ensure consistency of the fitness testing procedures[68] and is also present at the first initial meeting. Thisindividual is responsible for quality control throughoutthe fitness-testing portion of the trial. The fitness testersare blind to the treatment conditions of the participants.Both parents are given accelerometers to wear for 1week and instructed on how to enter information abouteach day’s activity in a log. Fitness testers provide a shorttraining session on how to wear and use the accelerome-ters. After the 1 week wear of accelerometers, partici-pants are randomized at a 1:1 ratio to eitherintervention or control group, using an online random-izer program. Participants as well as the research assis-tants and project coordinator are aware of the groupallocations, but all fitness testers are blinded to treat-ment allocation. The project coordinator and researchQuinlan et al. BMC Public Health  (2017) 17:875 Page 4 of 10assistants have to be aware of the condition to whichparticipants are randomized in order to deliver theappropriate materials. The project coordinator andresearch assistant meet with participants at their homeor location of choice to go through their specific inter-vention materials. Two people attend the house visits forsafety reasons.After the initial 6 week intervention period, couplesare given online follow-up questionnaires sent via emailto complete and accelerometers are dropped off to theirhouse to be worn for another week and then are pickedup by the research assistant. Contact is made initiallywith a phone call by the research assistant to setup ameeting time with participants and to prime them forthe emailed online questionnaire. Both groups receive asite “booster” session on the same material but the inter-vention group focuses on revisiting their experiencesover the past six-weeks and re-set goals and redefine/problem-solve obstacles. Participants in the controlgroup receive a booster session but this is more of a generalcheck in. The same protocol is followed at the 3 monthtime period. Thus, two booster sessions (six-weeks, 3months) are provided to all participants. At 6 monthsfollow-up (i.e., 8 months post-baby), parents are asked toreturn to the lab to complete a brief questionnaire, performthe final fitness test and participate in a brief end-of-trialquantitative questionnaire and qualitative interview toevaluate the impact of the intervention and usefulness ofthe intervention material. To gain a better understanding ofthe factors associated with physical activity we conductsemi-structured interviews with parents, in order to exam-ine both content fidelity (“what is done”) and process fidelity(“how it is done”) related to the delivery of the interventiontrial [18]. Although quantitative measurement of outcomeswill enable us to examine the potency of our intervention, aprocess evaluation (whereby participants are interviewed) isalso essential to examine the extent to which the program isdelivered and implemented as planned.To help study retention, we offer monetary compensationin the form of grocery store gift cards ($25 per participant,increasing by $5 each assessment) across the study.InterventionCouples randomized to the intervention conditionreceive a post-baby physical activity workbook thatserves as the template for a dialogue with the researchassistant for the study. The intervention booklet wasinformed by the Theory of Planned Behavior (TPB) con-cepts and preliminary results of our prior trials [42], aswell as the components that have been successful inprior intervention research with mothers and couple-based health interventions [10, 11, 17, 21, 22, 34, 37].The booklet consists of two main sections. Physicalactivity guidelines are presented in the introductorysection of the guide in order to define what is meant byregular physical activity and set the behavioral context.The first section focuses on the benefits of post-partumphysical activity on immune function, a better night’ssleep, increase in overall energy levels, control of foodcravings, reduction of pain, and finally prevention andtreatment of baby blues. This section is intended to tar-get our prior findings where affective attitudes and thebelief that regular physical activity can reduce stress pre-dicted those parents who were active from those whowere not. The section concludes with a brainstormingexercise for couples where they list physical activitiesthat they have found fun in the past, activities that maybe enjoyable with their new baby, and activities that theymight find enjoyable to do together. This brainstormedlist helps create the template for physical activity plan-ning/problem solving in the second section by context-ualizing what the participants would like to do.The second section guides participants through theprocess of finding time and planning for postpartumphysical activity as well as identifying barriers andstrategies to meet recommended guidelines via self-regulatory approaches [28, 52, 59] both personally andas a couple. Participants brainstorm a list of potentialand past barriers (and then strategies to overcome these)when setting their physical activity goals. This section isintended to target the control barriers of regular physicalactivity that were identified in our prior research onparents and to improve self-regulatory strategies. Thecontent addresses social support strategies as a couple,with friends/or extended family, problem solving aroundbad weather, and low-cost activities as well as copingwith fatigue. The section concludes with a discussion ofa re-set day (often Sunday) where the couple canreorganize their physical activity goals and plans for thefollowing week and reflect on what “worked” and what“didn’t work” from the previous week. The emphasis isplaced on how the couple can support each other toovercome barriers to physical activity either by sharingresponsibilities or doing more activity together. For anoutline of the study materials, please see the Additionalfile 1 and for an outline of the consent form please seeAdditional file 2. The two booster sessions (6 weeks and3 months) serve to re-open the dialogue and assess howthe couple is proceeding with in-person meetings betweenthe couple and the research assistant. The benefits of phys-ical activity, enjoyable activities to do, and goal setting andproblem solving between the participants is re-exploredand alternative plans and solutions are discussed if needed.Couples in the control group receive physical activityguidelines and verbal presentation on the importance ofphysical activity post-partum. More specifically, fathersin the control condition receive the Recommendationsfor Physical Activity for Adults recommending 150 minQuinlan et al. BMC Public Health  (2017) 17:875 Page 5 of 10of activity per week in bouts of 10 min and additionalrecommendations and guidelines about intensity, fre-quency and duration as well as ways to meet the recom-mended physical activity guidelines through structuredand unstructured, and endurance and strength activities.Mothers in the control condition receive a comparableguide, entitled Post-partum Physical Activity Guidelines,which has relatively similar content. Mothers are alsoadvised to incorporate kegel, core, and strengthening ex-ercises into their routine.Outcome measuresPrimary outcome measure:Change in Objective and Self-reported Physical ActivityPhysical activity is measured objectively for seven consecu-tive days using the GT1M Activity Monitor at each timeperiod (baseline, 6 weeks, 3 months, 6 months). It is de-signed to ascertain normal human movement withoutimpeding activity and has been shown to provide valid andreliable estimates of physical activity [31]. Seven days hasbeen proposed as an appropriate number of days for wear-ing a physical activity monitor to reliably estimate habitualphysical activity [36, 63]. This length of time also aligns withvalidated self-report measures such as the Godin LeisureTime Exercise Questionnaire (GLTEQ) [26] and PhysicalActivity Recall (PAR) [56] as well as national physical activityrecommended guidelines, all of which use a 7 day referenceperiod [62]. The activity monitor is attached to an elasticbelt and worn at the waist above the left hip. Best practicerecommendations for accelerometry wear time suggestchoosing a length of time that is sufficient to capture habit-ual physical activity while not becoming overly burdensomeon participants or study resources [36]. Participants areinstructed to wear the monitor from when they get up inthe morning to when they go to bed and for at least 10 hand to remove the monitors at night and while swimming,bathing, or showering. Participants also complete a daily log/ diary that identifies when the accelerometer is removed,unusual circumstances and structured activities.Both acceleration and step-count are obtained usingthe monitor. Physical activity is assessed by measuringduration (total minutes worn, total movement counts/day, total minutes of sedentary, moderate-vigorous, andvigorous activity/day), frequency (bouts of sedentary,moderate-vigorous, and vigorous activity/day), andintensity. To calculate these variables the monitor isprogrammed to store data at 10 s intervals on each day.As a secondary physical activity outcome, we use a self-report measure with the modified Godin Leisure-TimeExercise Questionnaire (GLTEQ) [26] asked at all four timepoints. The GLTEQ contains three questions, which assessthe frequency of mild, moderate, and strenuous activity per-formed for at least 15 min of duration during free time in atypical week. A total GLTEQ score will be calculated byadding the frequency of physical activity within the moder-ate, and strenuous categories. An independent evaluation ofthis measure found its reliability and validity to comparefavourably to nine other self-report measures of exercisebased on various criteria including test-retest scores, object-ive activity monitors, and fitness indices [30].Secondary outcome measures:Motivation for physical activity is measured using the con-structs of the theory of planned behavior and self-regulation strategies. These have been validated in parentpopulations [49, 50]. Items will measure all components ofthe model (affective attitude, instrumental attitude, injunct-ive norm, descriptive norm, perceived control, planning)including behavioral, normative, and control beliefs devel-oped from prior pilot work in parents [37]. Five items areused to assess affective attitude and instrumental attitudeand are measured on a 5 pt. scale. The items ask parentsabout their beliefs regarding physical activity behaviour overthe next 6 weeks (i.e. “Over the next six weeks, engaging inphysical activity on a regular basis would be … 1) Extremelyunenjoyable to 5) extremely enjoyable”). Three items areused to measure subjective norms on a 5-point scale ran-ging from strongly disagree to strongly agree. Three itemsmeasuring perceived control are used to assess participants’confidence that they can be regularly active over the next 6weeks on a 5-point scale (strongly disagree to stronglyagree). Intentions are measured with two items with 5-point scales (i.e. “Over the next six weeks, I am motivatedto be physically active on a regular basis, and 2) Over thenext six weeks I am determined to be physically active on aregular basis”). Control beliefs over perceived barriers aremeasured by asking participants to select the importance ofeach factor in preventing them from participating in150 min of moderate to vigorous physical activity per week.Possible barriers include items such as family activities,work, mood, stress etc. Participants answer on a 5-pointscale from “1) Does not prevent me at all, to 5) Preventsme a great deal”). The self-regulation items have beenadapted from other sources [59, 64] and included 8 itemsto be answered on a 5 point scale from “Never” to “Veryoften”. For example, questions include items such as, “Overthe past 6 weeks, I kept track of my physical activity in adiary or log”, and “Over the past 6 weeks, I set short-term(daily or weekly) goals for leisure-time physical activity.”Musculoskeletal fitness Grip strength, push ups, sit &reach flexibility, partial curl-ups, vertical jump, and back ex-tension will be measured to determine the musculoskeletalfitness of both the children and parents using the proce-dures established by Gledhill and Jamnik [25] Change inmusculoskeletal fitness from baseline to 6 months(i.e., post-intervention) will be examined.Quinlan et al. BMC Public Health  (2017) 17:875 Page 6 of 10Demographics A brief section in the baseline question-naire assesses characteristics including age, gender, maritalstatus, ethnicity, level of education, health background,employment information, sleep, smoking behaviour, alcoholdrinking and general eating behaviours.Evaluation of intervention A brief end-of-program inter-view is conducted for two main purposes. The first is to gaina deeper understanding of parent’s attitudes towards phys-ical activity and to provide them with an opportunity toexpand verbally on their experiences. Questions will includeasking parents to talk about how their lifestyle was beforethe birth of their child to afterwards, if their physical activityhas changed and what barriers they faced over the durationof the study. The second part of the interview will endeavorto determine how parents perceived the intervention mate-rials and the delivery of the materials. Fidelity questions willbe guided by the key points discussed in the article byDumas et al. [18]. For example, questions will aim to ensurethe intervention was delivered as designed, that the deliverydid not change throughout the study, that it was deliveredwith consistency and with effective communication acrossthe duration of the study and that participants adhered totheir particular condition. Six questions pertaining to inter-vention fidelity will be included in the interview including,“Did you feel the information provided to you in the work-book and from the meetings with the research assistanthelped to increase your physical activity?”, “Did you find themeeting sessions with the research investigator useful?”,“Have you been able to incorporate the strategies providedin the workbook and the ones you brainstormed during themeeting sessions?”, “Do you have any suggestions as to howthe workbook or mini counseling sessions could be moreuseful for helping you increase your physical activity?”,“Did you find the check-in sessions helped you both worktogether to come up with a plan to increase your physicalactivity?”, and “Did you find the information and check-insessions helped you both to work together to increaseyour physical activity?”.Analysis strategyMissing data will be evaluated for patterns of missingnessfor each psychosocial variable and behavior at all time pointsusing the dummy coding procedures of Allison [2]. Depend-ing on the outcome of these tests (e.g., missing at random,missing completely at random, etc.) we will initiate theappropriate missing data handling strategy. Intention to treatanalyses will also be performed in addition to sensitivityanalysis procedures. An assessment of covariates will also beperformed. As one would expect during early parenthoodmany factors may contribute to inactivity which include butare not limited to child care status, leave status, baselinequality of life and other general demographics. The RCTapproach aids in some equalization in the group x timeeffect of these factors, yet it is acknowledged that some ofthese confounds may affect the time effect regardless ofrandomisation.To address the first objective, hierarchical linear modelingwill be used in HLM 6.0. First, a Level-1 no intercept modelwill be specified such that a main effect will be entered forfather (0 =Mother; 1 = Father), Mother (0 = Father; 1 =Mother), a Father linear trend (0 = baseline; 1 = 6 months),and a Mother linear trend with all coefficients set to random.In this model, the main effects for the fathers and mothers’intercepts represent their respective baseline minutes ofMVPA, whereas the linear trends represent the change inMVPA (or not) over the 6-month interval. At Level-2, cross-level interactions will be added such that condition (0 = con-trol; 1 = intervention) predicts the fathers’ Level-1 intercept/ slope and the mothers’ Level-1 intercept / slope. These po-tential interactions will determine whether baseline MVPAis similar between conditions and whether the potentialchange in MVPA across time is similar between conditionsaccounting for the couple variation. Second, the fathers vs.mothers’ coefficients will be statistically compared using themultivariate hypothesis testing procedure (e.g., to determineif the magnitude of change in the minutes of MVPA is thesame for fathers and mothers). Third, the correlationsamong the fathers and mothers’ intercepts and slopes will beexamined to determine, for example, whether the mothers’baseline minutes of MVPA are significantly associated withtheir own change in MVPA and / or their fathers’ change inMVPA (and vice versa).To address the second and third objectives / hypothesesconcerning the motivational, health-related quality of life,and health-related fitness outcomes, the same analyticalapproach as outlined in relation to objective 1 will be usedwhen examining the variables as outcomes. However, toexamine whether the Theory of Planned Behavior (TPB)variables explain the potential MVPA differences betweenconditions (i.e., whether the TPB variables mediate the con-dition/MVPA relationship), the appropriate Level-1 medi-ation analysis approach [32, 33] will be used treating theTPB variables as time varying covariates [60] whileaccounting for the couple variation. Finally, the fourth ob-jective / hypothesis (i.e., whether season, gender) potentiallymoderate the condition / outcome relationships) will beexamined by including the time invariant covariates (e.g.,gender) at level-2 of the hierarchical model (i.e., by creatingcross-level interactions to predict the fathers/wives’ inter-cepts and slopes at Level-1) and the time varying covariates(e.g., motivation variables, season) at Level-1 of the model.The primary investigator and project coordinator will haveaccess to the final trial data set.Justification of sample sizeIt is recognized that two analytical approaches can be uti-lized in longitudinal couple studies within hierarchical linearQuinlan et al. BMC Public Health  (2017) 17:875 Page 7 of 10modeling. First, a 3-level model can be created whererepeated assessments (Level-1) are nested within the individ-ual (Level-2) that are nested within the couple (Level-3) [4].However, we have chosen to utilize the more commonapproach, which is to nest the individual repeated assess-ments (Level-1) within the couple (Level-2) ([4]; S. [43]).Therefore, we used the OpDes Program for power estima-tion of hierarchical linear models (S. W. [44]) to calculatethe sample size needed for our analyses. Specifically, with afrequency of 4 measurement occasions, a duration of6 months, within-person variance of 1.0, a growth rate of1.0, and a moderate effect size (.40), a total of 200 couples(i.e., 100 couples per condition) are needed to show a signifi-cant adherence to MVPA as measured via accelerometry.The effect size represents the low-end of findings from priorintervention research with this demographic [17, 21, 22, 34,38], yet it is clearly in the clinically meaningful range (D.E.R.[65]). These studies showed mean increases of moderate tovigorous physical activity of 80 min per week, which is overhalf of the recommended weekly activity for public health[62]. Our sample size includes a potential 25% attrition ratesimilar to the longitudinal study (thus total recruitmentN = 267. The attrition in the prior trial was actually 15%[48], but we sought to oversample to accommodate the ac-tive component of this experimental trial compared to theprior passive prospective design. Our over-sampling proce-dures account for attrition due to second pregnancy or otherpossible reasons for drop out such as break-up, movingaway, etc. The prediction-based research will be examinedby group condition as well as via the collapsed sample formediation analyses. Considering an average of five predictorIVs (TPB model), and using a small-medium effect size(f2 = .10) we will have sufficient power (.80) to evaluate thesepredictors at an alpha of .05. Our longitudinal studyalso supported the use of a small-medium effect sizeas an appropriate criterion [47]. Finally, the evaluationof physiological outcomes of participants across timewill follow a 2 (condition) × 2 (time) interaction. Theproposed sample size is, therefore, more thanadequate to ensure sufficient statistical power for thephysiological measurements.ResultsThe study is on-going with recruitment wrapping up inlate 2017. Ethical approval was obtained, and the trialwas registered with a government clinical trials database.The study has followed the Standard Protocol Items:Recommendations for Intervention Trials (SPIRIT) [14, 15]and the full checklist can be found in Additional file 3. Todate a total of 152 couples have been recruited with 88couples who have completed all four measures. Sixteencouples have dropped out after baseline testing due to avariety of reasons including not enough time, moving, andpost-partum depression. Remaining participants areFig. 1 Participant Flow DiagramQuinlan et al. BMC Public Health  (2017) 17:875 Page 8 of 10expected to wrap up all measures by early 2018. Please seeFig. 1 for the participant flow chart [14, 15].DiscussionThis protocol describes the implementation of arandomized controlled trial that utilizes motivationaland self-regulation strategies to try and maintain and/orincrease physical activity among new parents. Researchfindings could be useful in public health in providingeffective strategies to new parents to help prevent thedecline in physical activity that often accompanieshaving a newborn. Additionally, findings may help toinform future interventions aimed at increasing physicalactivity among new parents as well as informing publichealth materials for new parents. Findings from this trialwill be disseminated in peer-reviewed journals andpresented at academic conferences.Additional filesAdditional file 1: Outline of intervention materials. (DOCX 14 kb)Additional file 2: Consent form. (DOCX 23 kb)Additional file 3: SPIRIT 2013 Checklist: Recommended items to addressin a clinical trial protocol and related documents. (DOC 122 kb)AcknowledgementsNot applicable.FundingThe trial received funding from the Canadian Institutes of Health Researchgrant #133614. The funding body had no role in the design or collection ofdata for this study.Availability of data and materialsData will be analyzed after completion of the study and therefore theavailability of data is not applicable for this particular manuscript. Studymaterials are available by contacting the corresponding author onreasonable request.Authors’ contributionsRR designed the study and the intervention materials. AQ and RR drafted themanuscript. MB, CB, DS and DW all contributed to the revision of themanuscript. All authors read and approved the final version of the manuscript.Ethics approval and consent to participateThe study received ethical approval from the University of Victoria HumanResearch Ethics Board reference #11-036. All participants signed an informedconsent form prior to participating.Consent for publicationConsent from participants was obtained to publish the data as group data only.Competing interestsThe authors declare they have no competing interests.Publisher’s NoteSpringer Nature remains neutral with regard to jurisdictional claims inpublished maps and institutional affiliations.Author details1Behavioural Medicine Laboratory, University of Victoria, 3800 Finnerty Rd.,Victoria, B.C. V8P-5C2, Canada. 2University of British Columbia, Vancouver, BC,Canada. 3The Pennsylvania State University, State College, PA, USA.4Dalhousie University, Halifax, NS, Canada.Received: 14 September 2017 Accepted: 24 October 2017References1. Ajzen I. The theory of planned behavior. Organ Behav Hum Decis Process.1991;50:179–211.2. Allison PD. Missing Data. Thousand Oaks: Sage Publications; 2002.3. Arden-Close E, McGrath N. Health behavior change interventions forcouples: a systematic review. Br J Health Psychol. 2017;22:217–37.4. Atkins DC. Using multilevel models to analyze couple and family treatmentdata: basic and advanced issues. J Fam Psychol. 2005;19:98–110.5. Bandura A. Health promotion from the perspective of social cognitivetheory. Psychol Health. 1998;13:623–49.6. Bauman A, Reis RS, Sallis JF, Wells JC, Loos RJF, Martin BW, Lancet PhysicalActivity Series Working Group. Correlates of physical activity: why are somepeople physically active and others not? Lancet. 2012;380:258–71.7. Bellows-Riecken KH, Rhodes RE. A birth of inactivity? A review of physicalactivity and parenthood. Prev Med. 2008;46:99–110.8. Bize R, Johnson JA, Plotnikoff RC. Physical activity level and health-relatedquality of life in the general adult population: a systematic review. PrevMed. 2007;45:401–15.9. Burke V, Beilin LJ, Dunbar D, Kevan M. Changes in health-related behavioursand cardiovascular risk factors in young adults: associations with living witha partner. Prev Med. 2004;39:722–30.10. Burke V, Giangiulio N, Gillam HF, Beilin LJ, Houghton S. Physical activity andnutrition programs for couples: a randomized controlled trial. J ClinEpidemiol. 2003;56:421–32.11. Burke V, Giangiulio N, Gillam HF, Beilin LJ, Houghton S, Milligan RAK. Healthpromotion in couples adapting to a shared lifestyle. Health Educ Res. 1999;14:269–88.12. Candelaria JI, Sallis JF, Conway TL, Saelens BE, Frank LD, Slymen DJ.Differences in physical activity among adults in households with andwithout children. J Phys Act Health. 2012;9:985–95.13. Carraro N, Gaudreau P. Spontaneous and experimentally induced actionplanning and coping planning for physical activity: a meta-analysis. PsycholSport Exerc. 2013;14(2):228–48.14. Chan A-W, Tetzlaff JM, Altman DG, Laupacis A, Gøtzsche PC, Krleža-Jerić K,Hróbjartsson A, Mann H, Dickersin K, Berlin J, Doré C, Parulekar W,Summerskill W, Groves T, Schulz K, Sox H, Rockhold FW, Rennie D, Moher D.SPIRIT 2013 Statement: Defining standard protocol items for clinical trials.Ann Intern. Med 2013;158:200–207.15. Chan A-W, Tetzlaff JM, Gøtzsche PC, Altman DG, Mann H, Berlin J, DickersinK, Hróbjartsson A, Schulz KF, Parulekar WR, Krleža-Jerić K, Laupacis A, MoherD. SPIRIT 2013 Explanation and Elaboration: Guidance for protocols ofclinical trials. BMJ 2013;346:e7586.16. Colley RC, Garriguet D, Janssen I, Craig CL, Clarke J, Tremblay MS.Physical activity of Canadian adults: accelerometer results from the 2007to 2009 Canadian health measures survey, health reports. StatisticsCanada. 2011;22:1–8.17. Cramp AG, Brawley LR. Moms in motion: a group-mediated cognitive-behavioralphysical activity intervention. Int J Behav Nutr Phys Act. 2006;3:1479.18. Dumas JE, Lynch AM, Laughlin JE, Smith EP, Prinz RJ. Promotingintervention fidelity: conceptual issues, methods, preliminary results fromthe early alliance prevention trial. Am J Prev Med. 2001;20:38–47.19. Elek SM, Hudson DB, Fleck MO. Couples' experiences with fatigue duringthe transition to parenthood. J Fam Nurs. 2002;8:221–40.20. Evenson RJ, Simon RW. Clarifying the relationship between parenthood anddepression. J Health Soc Behav. 2005;46:341–58.21. Fahrenwald NL, Atwood JR, Noble-Walker S, Johnson DR, Berg K. Arandomized pilot test of "moms on the move": a physical activityintervention for WIC mothers. Ann Behav Med. 2004;27:82–90.22. Fjeldsoe B, Miller YD, Marshall AL. MobileMums: a randomized controlled trial ofan SMS-based physical activity intervention. Ann Behav Med. 2010;39:101–11.23. Gilinsky AS, Dale H, Robinson C, Hughes AR, McInnes R, Lavallee D. Efficacyof physical activity interventions in post-natal populations: systematicreview, meta-analysis and content coding of behaviour change techniques.Health Psychol Rev. 2015;9:244–63.Quinlan et al. BMC Public Health  (2017) 17:875 Page 9 of 1024. Gillison FB, Skevington SM, Sato A, Standage M, Evangelidou S. The effectsof exercise interventions on quality of life in clinical and healthypopulations: a meta-analysis. Soc Sci Med. 2009;68:1700–10.25. Gledhill N, Jamnik V. Canadian physical activity, fitness and lifestyleapproach. 3rd ed. Ottawa: Canadian Society for Exercise Physiology; 2003.26. Godin G, Shephard RJ. A simple method to assess exercise behavior in thecommunity. Can J Appl Sport Sci. 1985;10:141–6.27. Gollwitzer PM. Action phases and mind-sets. In: Higgins ET, Sorrentino RM,editors. Handbook of motivation and cognition: foundations of socialbehavior, vol. 2. New York: Guilford Press; 1990. p. 53–92.28. Gollwitzer PM. Implementation intentions: strong effects of simple plans.Am Psychol. 1999;54:493–503.29. Hull EE, Rofey DL, Robertson RJ, Nagle EF, Otto AD, Aaron AJ. Influence ofmarriage and parenthood on physical activity: a two-year prospectiveanalysis. J Phys Act Health. 2010;7:577–83.30. Jacobs DR, Ainsworth BE, Hartman TJ, Leon AS. A simultaneous evaluationof ten commonly used physical activity questionnaires. Med Sci SportsExerc. 1993;25:81–91.31. Kelly L, McMillan D, Anderson A, Fippinger M, Fillerup G, Rider J. Validity ofactigraphs uniaxial and triaxial accelerometers for assessment of physicalactivity in adults in laboratory conditions. BMC Med Phys. 2013;13:1–7.32. MacKinnon DP, Fairchild AJ, Fritz MS. Mediation analysis. Annu Rev Psychol.2007;58:593–614.33. Mackinnon DP, Lockwood CM, Hoffman JM, West SG, Sheet V. Acomparison of methods to test mediation and other intervening variableeffects. Psychol Methods. 2002;7:83–103.34. Mailey, E. L., & McAuley, E. (2013). Impact of a brief intervention on physicalactivity and social cognitive determinants among working mothers: arandomized trial. J Behav Med.35. Martire LM, Schulz R, Helgeson VS, Small BJ, Saghafi EM. Review andmeta-analysis of couple-oriented interventions for chronic illness. AnnBehav Med. 2010;40:325–42.36. Matthews C, Hagstromer E, Pober D, Bowles H. Best practices for usingphysical activity monitors in population-based research. Med Sci SportsExerc. 2012;44:S68–76.37. McIntyre CA, Rhodes RE. Correlates of physical activity during the transitionto motherhood. Women Health. 2009;49:66–83.38. Miller Y, Stewart B, Trost G, Brown W. Mediators of physical activtybehavior change among women with young children. Am J Prev Med.2002;23:98–103.39. Morgan PJ, Lubans DR, Callister R, Okely AD, Burrows T, Fletcher R,Collins C. The ‘healthy dads, healthy kids’ randomized controlled trial:efficacy of a healthy lifestyle program for overweight fathers and theirchildren. Int J Obes. 2011;35:436–7.40. Pollman-Schult M. Parenthood and life satisfaction: why Don’t childrenmake people happy? J Marriage Fam. 2014;76:319–36.41. Prochaska JO, Velicer WF. The transtheoretical model of health behaviorchange. Am J Health Promot. 1997;12:38–48.42. Quinlan A, Rhodes RE, Blanchard CM, Naylor PJ, Warburton DER. Familyplanning to promote physical activity: a randomized controlled trialprotocol. BMC Public Health. 2015;15:1–9.43. Raudenbush S, Brennan R, Barnett R. A multivariate hierarchical model forstudying psychological change within married couples. J Fam Psychol. 1995;9:161–74.44. Raudenbush SW, Bryk TA. Hierarchical linear model: applications and dataanalysis. 2nd ed. Thousand Oaks: Sage; 2002.45. Rebar A, Stanton R, Geard D, Short CE, Duncan M, Vandelanotte C. A meta-meta-analysis of the effect of physical activity on depression and anxiety innon-clinical adult populations. Health Psychol Rev. 2015;9(3)366–78.46. Rhodes RE. The evolving understanding of physical activity behavior: amulti-process action control approach. In: Elliot AJ, editor. Advances inmotivation science; 2017. p. 171–205.47. Rhodes RE, Benoit C, Blanchard CM, Symons Downs D, Levy Milne R, NaylorPJ, et al. Predicting regular physical activity continuation after the onset offirst-time parenthood. Ann Behav Med. 2010;39:s31.48. Rhodes RE, Blanchard CM, Benoit C, Levy-Milne R, Naylor PJ, Symons DownsD, Warburton DER. Physical activity and sedentary behavior across 12months in cohort samples of couples without children, expecting their firstchild, and expecting their second child. J Behav Med. 2014a;37:533–42.49. Rhodes RE, Blanchard CM, Benoit C, Levy-Milne R, Naylor PJ, Symons DownsD, Warburton DER. Social cognitive correlates of physical activity across 12months in cohort samples of couples without children, expecting their firstchild and expecting their second child. Health Psychol. 2014b;33:792–802.50. Rhodes RE, Blanchard CM, Benoit C, Naylor PJ, Levy-Milne R, Warburton DER,Symons Downs D. Belief-level markers of physical activity among youngadult couples: comparisons across couples without children and newparents. Psychol Health. 2014;29:1320–40.51. Rhodes, R. E., Bredin, S. S. D., Janssen, I., Warburton, D. E. R., & Bauman, A.(2017). Physical activity: Health impact, prevalence, correlates andinterventions. Psychol Health. https://doi.org/10.1080/08870446.2017.1325486.52. Rhodes RE, Naylor PJ, McKay HA. Pilot study of a family physical activityplanning intervention among parents and their children. J Behav Med.2010;33:91–100.53. Rhodes RE, Quinlan A. The family as a context for physical activitypromotion. In: Beauchamp MR, Eys MA, editors. Group dynamics in exerciseand sport psychology. second ed. New York: Routledge; 2014. p. 203–21.54. Rhodes RE, Quinlan A. Predictors of physical activity change in observationaldesigns. Sports Med. 2015;45:423–41.55. Rhodes RE, Temple VA, Tuokko HA. Evidence-based risk assessment andrecommendations for physical activity clearance: cognitive andpsychological conditions. Appl Physiol Nutr Metab. 2011;36(S1):S113–53.56. Sallis JF, Haskell WL, Wood PD, Fortmann SP, Rogers T, Blair SN, PaffenbargerR. Physical activity assessment methodology in the five City project. Am JEpidemiol. 1985;121:91–106.57. Schulz KF, Altman DG, Moher D, CONSORT Group. CONSORT 2010statement: updated guidelines for reporting parallel group randomisedtrials. Ann Intern Med. 2010;152:e24.58. Schwarzer R. Modeling health behavior change: how to predict and modify theadoption and maintenance of health behaviors. Appl Psychol. 2008;57:1–29.59. Sniehotta FF, Scholz U, Schwarzer R. Action plans and coping plans forphysical exercise: a longitudinal intervention study in cardiac rehabilitation.Br J Health Psychol. 2006;11:23–37.60. Spence JC, Blanchard CM, Clark M, Plotnikoff R, Storey KE, McCargar L. The roleof self-efficacy in explaining gender differences in physical activity amongadolescents: a multi-level analysis. J Phys Act Health. 2010;7(2):176–83.61. Statistics Canada. (2014). Population by sex and age group, by province andterritory (Number, both sexes). CANSIM, table 051-0001. http://www.statcan.gc.ca/tables-tableaux/sum-som/l01/cst01/demo31c-eng.htm. Accessed 1 June 2017.62. Tremblay MS, Warburton DER, Janssen I, Paterson DH, Latimer AE, RhodesRE. New physical activity guidelines for Canadians. Appl Physiol Nutr Metab.2011;36:36–46.63. Trost SG, McIver KL, Pate RR. Conducting accelerometer-based activityassessments in field-based research. Med Sci Sports Exerc. 2005;37:S531–43.64. Umstattd MR, Motl R, Wilcox S, Saunders R, Watford M. Measuring physicalactivity self-regulation strategies in older adults. J Phys Act Health. 2009;6:S105–12.65. Warburton DER, Bredin SSD. Reflections on physical activity and health:what should we recommend? Can J Cardiol. 2016;32:495–504.66. Warburton DER, Bredin SSD, Charlesworth S, Foulds H, McKenzie DC,Shephard RJ. Evidence-based risk recommendations for best practices in thetraining of qualified exercise professionals working with clinical populations.Appl Physiol Nutr Metab. 2011;36:S232–65.67. Warburton DER, Bredin SSD, Jamnik V, Gledhill N. Validation of the PAR-Q+and ePARmed-X+. Health Fitness J Canada. 2011;4:38–46.68. Warburton DER, Charlesworth SA, Foulds HJ, McKenzie DC, Shephard RJ,Bredin SSD. Qualified exercise professionals: best practice for work withclinical populations. Can Fam Physician. 2013;59:759–61.69. Warburton DER, Nicol CW, Bredin SS. Health benefits of physical activity: theevidence. Can Med Assoc J. 2006;174:801–9.Quinlan et al. BMC Public Health  (2017) 17:875 Page 10 of 10


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