Predicting Physical Activity in Survivors of Breast Cancer: the Health Action Process Approach at the Intrapersonal Level

Vol.:(0123456789) 1 3 In e na ional Jou nal o Beha io al Medicine (2023) 30:777–789 h ps://doi.o g/10.1007/s12529-022-10140-3 FULL LENGTH MANUSCRIPT P edic ing Physical Ac i i y inSu i o s o B eas Cance : heHeal h Ac ion P ocess App oach a  heIn ape sonal Le el Ma ga idaSequei a1,2 · Cíce oPe ei a3 · Ma ia‑JoãoAl a ez1 Accep ed: 25 Oc obe 2022 / Published online: 9 No embe 2022 © In e na ional Socie y o Beha io al Medicine 2022 Abs ac Backg ound Bene i s ha e been es ablished o egula physical ac i i y (PA) and exe cise a e b eas cance , bu a decline o PA has also been a epo ed esul o b eas cance diagnosis and ea men s. The Heal h Ac ion P ocess App oach (HAPA) model has been shown o p edic a ious heal h beha io s, bu ew s udies ha e es ed i a he in ape sonal le el. The aim o he p esen s udy was o es whe he he HAPA cons uc s ha a e well con i med a he in e pe sonal le el also hold a he in ape sonal le el in a g oup o women su i o s o b eas cance . Me hod PA beha io s (N = 338) by nine su i o s o b eas cance we e obse ed o 6weeks, and he associa ions be ween he HAPA cons uc s and PA o e ime we e examined. Pa icipan s comple ed a ques ionnai e wi h he HAPA cons uc s ela ed o PA beha io (di ec s ep coun and sel - epo ed). Resul s A mul ile el model o beha io p edic ion ound ha op imis ic belie s abou abili y o ini ia e and main ain PA (sel -e icacy) we e posi i ely ela ed o in en ions o be ac i e, and hese in en ions p edic ed plans o be ac i e. PA was di ec ly and posi i ely p edic ed by planning and by con idence in he abili y o esume PA a e a b eak. Conclusion Sel -e icacy and planning a e associa ed wi h PA beha io wi hin women su i o s o b eas cance o e ime, which was no he case o he ou come expec ancies, social suppo , and ac ion con ol a his in ape sonal le el. A mul- ile el app oach o psychological p edic o s o PA can be use ul in g ounding in e en ions o su i o s o b eas cance . Keywo ds N-o -1 designs· Su i o s o b eas cance · Physical ac i i y· HAPA In oduc ion In ecen yea s, he ield o exe cise and physical ac i i y (PA) has unde gone b oad de elopmen o he p e en ion and managemen o di e en pa hologies, including cance . E idence indica es ha an absence o egula PA is ela ed wi h many mo e ypes o cance han p e iously hough , ha seden a y beha io may also ha e an in luence, and ha exe cise may imp o e su i al o hose diagnosed wi h colon and b eas cance [1]. As in es iga ion p oceeds, he e is less doub abou he ole o PA as a cen al suppo o b eas cance pa ien s, in iew o he sys emic bene i s o exe cise, dec ease in he isk o b eas cance - ela ed com- plica ions, and inc ease in quali y o li e and su i al [2]. The sys emic bene i s o egula PA and exe cise a e b eas cance diagnosis and ea men s lead o inc eased ae obic i ness, imp o ed quali y o li e and ac i i y ole ance, and educ ions in a igue, dep essi e symp oms, he apeu ic ox- ici y, and sleep dis u bances [3–6]. In spi e o hese bene i s, a dec ease in he le el o PA has been epo ed as a consequence o he e ec s associa ed wi h b eas cance diagnosis and ea men s, challenging he scien i ic communi y o iden i y he causes and he s a egies o change he p opensi y o his beha io . I is necessa y o iden i y he speci ic componen s o in e en ions ha acili- a e beha io al change o su i o s o b eas cance owa ds an inc ease o PA [7] in all h ee phases o su i o ship o * Ma ga ida Sequei a ma ga [email p o ec ed] Cíce o Pe ei a [email p o ec ed] Ma ia-João Al a ez mjal[email p o ec ed] 1 CICPSI, Faculdade de Psicologia, Uni e sidade de Lisboa, Lisbon, Po ugal 2 CIIAS, Escola Supe io de Saúde, Ins i u o Poli écnico de Se úbal, Se ubal, Po ugal 3 ICS, Ins i u o de Ciências Sociais da Uni e sidade de Lisboa, Lisbon, Po ugal 778 In e na ional Jou nal o Beha io al Medicine (2023) 30:777–789 1 3 his disease: he ime om diagnosis o he end o ea - men s, he ansi ion om ea men o ex ended su i al, and long- e m su i al [8]. I has been p oposed ha sound beha io heo ies can imp o e beha io change in e en ions by linking ele an causal ac o s o he beha io o he app op ia e beha io change echniques, including in e en ions seeking a egu- la p ac ice o PA o su i o s o cance [9]. T adi ional models o heal h beha io change, heo e ically based on g ounded heo ies such as social cogni i e heo y (SCT), ha e been shown o con ibu e o e ec i e in e en ions owa ds PA beha io , namely among su i o s o cance , including b eas cance [10, 11]. The s a e o esea ch in his a ea has ocused p ima ily on mo i a ional de e minan s o beha io al in en ions o in luence PA beha io , adi ion- ally gi ing less a en ion o pos -in en ional ac o s [12]. Recen ly, pos -in en ional and main enance ac o s ha e p o ed essen ial in in e en ions o PA beha io change, e en o cance su i o s [13], including he e ec o se - e al beha io change echniques on beha io al in en ion [14] de i ed om con ol heo y [15], ein o cing he idea ha sound beha io heo ies ha include sel - egula o y ac o s should be conside ed o change and long- e m sus ainabili y o occu . The Heal h Ac ion P ocess App oach (HAPA), suppo ed in he SCT [16], akes in o accoun a mo i a ional phase ha leads o in en ion o ma ion, ollowed by a pos -in en ional phase in ol ing oli ional sel -e icacy and s a egic planning. In he ini ial mo i a ional phase, an in en ion o ac is de el- oped; he HAPA speci ies isk awa eness, posi i e ou come expec ancies, and sel -e icacy as p edic o s o in en ions. Risk awa eness e e s o he pe cep ion o isk ha a speci ic beha io (o absence he eo ) ep esen s o one’s u u e heal h, which can ac as a igge o conside changing one’s heal h beha io . Ou come expec ancies e e o he an icipa ion o posi i e consequences esul ing om he beha io . Ac ion sel - e icacy designa es he posi i e op imis ic con ic ion ha one will be able o ini ia e a speci ic beha io . A e in en ions ha e been se , hey ha e o be ans o med in o de ailed ins uc ions on how o pe o m he desi ed ac ion in o de o ini ia e and subsequen ly main ain he beha io and eco e om possible lapses. The HAPA p oposes ha sel -e icacy, ac ion planning ( he exac planning o when, whe e, and how o implemen he in ended beha io ), coping planning ( he sel - egula ion s a egy ha in ol es he iden i ica ion o ba ie s ha endan- ge he in ended beha io and s a egies o o e come hem), and ac ion con ol (sel - egula o y skills and s a egies) con- ibu e o ansla ing in en ions in o ac ions. Ac ion con ol is a concu en sel - egula o y s a egy o e alua e whe he he beha io is app oaching wha is in ended and consis s o h ee di e en ace s: he awa eness o one’s own s anda ds, he sel -moni o ing, and he sel - egula o y e o [17]. Di - e en phase-speci ic sel -e icacy belie s a e dis inguished o add ess he espec i e challenges [16], al hough hey may be ha bo ed a he same poin in ime [18], which pe mi s hei agg ega ion. Pe cei ed sel -e icacy is needed h oughou he en i e p ocess; in o de o success ully y ha de and pe sis longe in he p ocess o beha io change, he pe cei ed abil- i y o main ain a heal h beha io in he ace o obs acles is equi ed, which is e med main enance sel -e icacy. Bu he e a e expe iences o ailu e and he need o eco e om se - backs, equi ing eco e y sel -e icacy, one’s con idence in one’s abili y o e u n o egula beha io , especially when i p o es o be complex. Iden i ied as a model wi h an open- a chi ec u e amewo k [18], he HAPA allows o ex ensions by he inclusion o addi ional cons uc s. One o hese is social suppo , which can be in luen ial ei he in he mo i a ional o in he oli ional s age, making an impac on in en ions as well as on beha io , pa icula ly o PA [19, 20]. The HAPA has been shown o be o good p edic i e alidi y ac oss a a ie y o di e en heal h- ela ed beha - io s, including se e al heal h-enhancing beha io s such as heal hy ea ing, ood sa e y beha io s, and PA [18]. In he la e , he HAPA has been es ed and demons a ed o be use ul in p edic ing PA a he in e pe sonal le el o obese adul s [19], e i ed elde ly [21], inac i e middle-aged women [22], and A ican Ame ican su i o s o b eas cance [23]. Mos o hese s udies ha e used s uc u al equa ion mod- eling, inding in en ion, main enance sel -e icacy [19, 21, 22], and social suppo [15, 19] as p edic o s o PA. In some s udies, pos -in en ional HAPA cons uc s o in e indi idual di e ences in egula p ac ice o PA we e no con i med, such as ac ion planning [22], ein o cing he need o cop- ing planning in he p ocess [23]. Howe e , he e is much less e idence o model e icacy a he in ape sonal le el [24], in e ms o how i s p edic ions a e adequa e o explain a pe son’s beha io o e ime, assuming ha one’s belie s, mo i a ions, a i udes, and beha io s a e no s a ic bu change in esponse o pe sonal and en i onmen al ac o s. Indeed, heo ies and models o beha io change, including he HAPA, ha e mos ly been es ed as explana ions o di - e ences be ween people. I is no clea ha hey can p e- dic he beha io o an indi idual pe son since ac o s ha p edic di e ences be ween indi iduals a e usually di e - en om hose p edic ing beha io wi hin indi iduals [25, 26], and associa ions a he in e pe sonal le el can di e subs an ially om associa ions a he in ape sonal le el [27]. This p oblem can be add essed using wi hin-pe son esea ch designs ha a e lexible enough o answe c i ical esea ch ques ions so ha we can expand he scope o he HAPA. These designs, some imes e e ed as N-o -1, and also known as single-pa icipan , wi hin-pe son, and single- case s udy designs, all unde he umb ella e m o me hods in ol ing sequences o epea ed measu emen s su icien ly equen o allow cha ac e iza ion o a sepa a e change p o- cess o each indi idual o uni o assessmen . While a single 779In e na ional Jou nal o Beha io al Medicine (2023) 30:777–789 1 3 N-o -1 s udy seeks o unde s and idiog aphic wi hin-pe son changes, esea che s migh also be in e es ed in agg ega ing hose p ocesses o each gene alizable conclusions, and in his case, he e m agg ega ed o cumula i e N-o -1 s udy can be used, e e ing o he same p inciple [28]. The e o e, N-o -1 designs allow esea che s o answe di e en ypes o esea ch ques ions. One migh ask whe he he pa e n o ela ionships among a iables in he model occu s in simi- la o di e en ways o each pa icipan o e ime, which would equi e epea ing he analysis sepa a ely o each pa - icipan . Equally in e es ing, hese esea ch designs pe mi examina ion o he p ocess by which he a iables wi hin he pa icipan s a e ela ed o e ime wi hou ques ioning he speci ici y o his p ocess o each indi idual. Besides he ela ion be ween a iables o e ime, he di - e ences in he ime- a ying associa ions be ween weekdays and weekends ha e also been conside ed, since PA beha io has been iden i ied as suscep ible o a ia ion o e he week [29]. N-o -1 designs ha e been used o es social cogni ion models and o p edic beha io wi hin indi iduals, inding some suppo o he abili y o he Theo y o Planned Beha - io o p edic PA beha io s in heal hy indi iduals [30] and in es ing he in luence o SCT cons uc s o indi idual PA le els in heal hy adul s [31]. Smi h e al. [31] sugges ha indi iduals make daily decisions, adop daily a i udes, and hold daily belie s abou engaging in a speci ic heal h beha - io ha will in luence hei cu en and u u e pe o mance conce ning ha beha io . These a ia ions in cogni ion and beha io may go unde ec ed when using be ween-pe son designs, demons a ing he po en ial limi a ions o such designs. As a as we know, a ew s udies ha e es ed he HAPA a he wi hin-pe son le el o heal h-enhancing PA. Some o hese s udies we e conduc ed o unning aining [32], phys- ical exe cise wi hin heal hy young adul s [27], educ ion o seden a y beha io [33], and PA and medica ion adhe ence wi hin olde adul s [24]. In e ms o cons uc s, isk pe cep- ion was ound o play a ela i ely mino ole in de e min- ing heal h- ela ed beha io s when mul iple heal h beha io s we e conside ed [34]. Ne e heless, gi en he se e i y and social ep esen a ion o b eas cance , i would be impo an o con inue o conside isk pe cep ion and i s ole in a sam- ple o su i o s o b eas cance . T ea men s and ollow-ups may be conside ed ac o s in cessa ion o PA, so eco e y sel -e icacy should be a ocus o his esea ch. In addi ion, s udies o he HAPA model es ed a he wi hin-pe son le el sugges ha planning-based in e en ions may no ha e he desi ed e ec s o p omo ing PA [24, 27, 33]. This cons uc he e o e equi es special a en ion when HAPA is es ed a his le el. In he cu en s udy, we used a wi hin-pe son esea ch design o examine how he cons uc s o he HAPA model changed o e ime (independen a iables) and how his change p edic ed daily PA (dependen a iable) in a g oup o women su i o s o b eas cance . Me hod A se o nine cumula i e N-o -1 obse a ions was conduc ed be ween Ap il and July 2019 o unde s and he in e ela ion- ships be ween he HAPA cons uc s and PA beha io in a g oup o su i o s o b eas cance , wi h daily and weekly obse a ions o e a pe iod o 6weeks. Pa icipan s Nine Po uguese women, su i o s o b eas cance in he phase o ansi ion om ea men o ex ended su i al and o long- e m su i al, who me he eligibili y c i e ia, being adul women (18 o 64yea s) who could walk independen ly and ha e comple ed b eas cance ea men s o mo e han 4mon hs, wi h li e acy and cogni i e le els ha allowed hem o p o ide hei in o med consen , o unde s and he pu pose o he s udy, and o use he ins umen s au ono- mously (Table1). P ocedu es The sample was ec ui ed by con enience, om cance pa ien s’ associa ions and h ough a snowball sampling me hod. Pa icipan s we e con ac ed by he i s au ho a e in o mally ag eeing o pa icipa e h ough he associa ion o o he pa icipan s’ ini ial con ac . A ace- o- ace mee ing wi h he i s au ho was held o p esen he aims o he s udy, i s po en ial bene i s, and he igh s o he pa icipan s. Upon ag eemen o pa icipa e, he in o med consen was signed. In his mee ing, pa icipan s Table 1 Cha ac e is ics o he pa icipan s (N = 9) Age, M (SD)49.0 (5.7) Ma i al s a us Ma ied 7 Single o di o ced 2 Educa ion le el Uni e si y g adua ion 7 Seconda y school 2 P o essional s a us Wo king 7 No wo king 2 Yea s ou om diagnosis, M (SD) 7.67 (5.3) B eas cance su ge y 9 B eas cance adju an ea men s 9 780 In e na ional Jou nal o Beha io al Medicine (2023) 30:777–789 1 3 comple ed an online ques ionnai e including sociodemo- g aphic and clinical da a p e iously iden i ied as being ela ed o egula p ac ice o PA among su i o s o b eas cance [35, 36]. Da a con iden iali y was assu ed ia he c ea ion o a pa icipan ’s code. In his p e-session, he da a collec ion o m was p esen ed and explained, and a pedome e (Xiaomi Mi Band 2®) was p o ided o each pa icipan . P e ious esea ch has shown his ool o be a alid and eliable de ice o obse ing s ep coun s o physical ac i i ies as e alua ed by i s co ela- ion wi h a GT3X+ ac ig aphy accele ome e [37, 38]. The unc ioning o he de ice was explained, and pa icipan s we e asked o wea i e e y day and o eco d hei daily s eps. Addi ionally, pa icipan s we e con ac ed by elephone once a week o p omp comple ion and o oubleshoo any p oblems. Daily and weekly da a collec ion was pe o med o 6weeks h ough an Ecological Momen a y Assessmen (EMA) [39] using email o ex messages, acco ding o pe - sonal p e e ence (Supplemen al Ma e ial S1). EMA included he illing ins uc ions and he s a emen “Conside ing he Wo ld Heal h O ganiza ion's ecommenda ions o do a leas 150min o PA pe week” ollowed by each i em. This ec- ommenda ion was discussed wi h each pa icipan in he p e-session. A pilo s udy was conduc ed o es he ques ionnai es and he p ocedu es (daily and weekly assessmen s and da a collec ed) wi h i e psychologis s, and bo h we e discussed and adjus ed o he eedback ecei ed. The s udy was app o ed by he E hical Commi ee o he Facul y o Psychology, Uni e si y o Lisbon. Measu es Th ee se s o measu es we e collec ed h ough EMA: he HAPA cons uc s measu ed daily o e 42 unin e up ed days, he HAPA cons uc s measu ed weekly o e 6weeks and daily e alua ion o physical ac i i ies. Unless o he wise no ed, HAPA cons uc s we e assessed using single i ems wi h a esponse scale o 1 (s ongly disag ee) o 6 (s ongly ag ee). I ems we e adop ed om o he PA s udies ha ha e demons a ed cons uc alidi y and eliabili y o i ems measu ing he HAPA a iables [24, 27]. The empo al obse a ion o he a iables was based on heo e ical and empi ical in o ma ion. Pe o ming a heal h beha io in daily li e equi es cons an sel - egula o y e o s [16]. As a esul o he sel - egula o y objec i es o main e- nance sel -e icacy, planning, and ac ion con ol, signi ican a iance in pa icipan s’ beha io ac oss days is expec ed o main ain es ablished goals, educing disc epancies be ween one’s beha io and sel -se in en ions. Daily e alua ion and a ia ions o hose a iables we e ound in se e al heal h beha io s [41, 42], ex ended o ac ion sel -e icacy [43]. On he o he hand, isk pe cep ion, ou come expec ancies, and eco e y sel -e icacy a e a iables heo e ically and empi i- cally less pe meable o daily change [18, 44]. The e o e, i is be e o measu e hem o e longe pe iods han he day, wi h he week being a ime pe iod ound in some s udies (e.g., [44]). Daily Measu es The daily e alua ion o PA included wo di e en me hods sensi i e o daily a ia ions, conside ing he ad an ages and disad an ages o each [45]: daily s eps coun and sel - epo . Fo sel - epo ed assessmen , mode a e- and high- in ensi y ac i i ies we e conside ed, wi h he ollowing i ems: “Rega ding he mode a e physical ac i i y p ac iced oday (e.g., walking), no e he o al minu es,” “I p ac iced he ollowing mode a e ac i i y,” “Rega ding igo ous physi- cal ac i i y p ac iced oday (physical ac i i y ha le you b ea hless) no e he o al minu es,” “I p ac iced he ollow- ing igo ous ac i i y.” To know i he o al daily s ep coun included he PA assessed indi ec ly, pa icipan s we e asked “Did you use he pedome e in his ac i i y?” bo h o mode - a e and igo ous ac i i ies. The di ec me hod conside ed he daily s ep coun by he pedome e . I any PA o exe cise was pe o med wi hou he use o he pedome e (e.g., swimming, kickboxing), da a we e con e ed in o “s ep equi alen s” using he ac i i y’s speci ic Me abolic Equi alen o he Task (MET) le el [46, 47]. These s ep equi alen s we e hen combined wi h he aw s ep-coun s o gi e an o e all es ima ion o s eps pe day. In addi ion o he daily obse a ion o beha io , some o he HAPA cons uc s we e assessed daily using eigh i ems, asking abou beha io al in en ion: “I in end o p ac ice physi- cal ac i i y omo ow and con ibu e o he weekly 150min”; o ac ion sel -e icacy: “I’m con iden ha omo ow I will be able o p ac ice physical ac i i y”; ac ion planning was measu ed wi h he i em: “I’ e al eady planned when, whe e, and how o be able o p ac ice physical ac i i y omo ow”; coping planning: “I ha e plans o o e come he ba ie s ha may a ise omo ow o p e en me om p ac icing physi- cal ac i i y”; main enance sel -e icacy: “I’m con iden ha omo ow I will be able o p ac ice physical ac i i y, e en i di icul ies a ise”; social suppo : “I ha e someone o sup- po me in ca ying ou he physical ac i i y scheduled o omo ow.” Ac ion con ol was assessed by wo i ems, one o he awa eness o one’s own s anda ds: “Today I was awa e o he goal I se mysel o p ac ice physical ac i i y and con- ibu e o he 150min pe week”; he o he o sel - egula o y e o : “Today I made an e o o mee my in en ion o p ac- ice physical ac i i y, in o de o con ibu e o he weekly 150min.” Unlike he o he cons uc s, ac ion con ol was asked abou in e e ence o he PA pe o med on ha cu - en day. 781In e na ional Jou nal o Beha io al Medicine (2023) 30:777–789 1 3 Some heo e ical aspec s we e conside ed ega ding he close ela ion be ween i ems and e ms o measu emen unde lying he HAPA cons uc s and he speci ic ele an measu emen issue, conce ning whe he esponden s pe - cei ed he sub le nuances be ween i ems. To add ess hese, he cons uc s assessed daily we e assigned o an independ- en sample o 11 women in a pilo s udy asking hem o g oup he i ems acco ding o simila i y and di e ences (see supplemen al ma e ial o a de ail explana ion o his pilo s udy (S2)). Pa icipan s g ouped he daily cons uc s as ollows: in en ion, sel -e icacy (g ouping ac ion sel -e icacy and main enance sel -e icacy), planning (g ouping ac ion planning and coping planning), ac ion con ol (g ouping awa eness o own s anda ds and sel - egula o y e o ), and social suppo . These we e he inal cons uc s conside ed o analysis. Weekly Measu es The weekly measu ed HAPA cons uc s we e isk awa e- ness, measu ed wi h he i em: “I know I may ha e new heal h p oblems ela ed o b eas cance ”; ou come expec an- cies, wi h he i em: “I eel ha by doing a leas 150min o physical ac i i y a week I can imp o e b eas cance ela ed p oblems”; and eco e y sel -e icacy, wi h he i em: “Once I s a p ac icing egula physical ac i i y, I will be able o main ain his p ac ice, e en i I s op o a while.” Da a Analysis Fo he di ec daily assessmen o PA, he inal a iable wi h he o e all es ima ion o s eps pe day was con e ed o walked dis ance (km). The PA da a collec ed by sel - epo was con e ed o a quan i a i e alue using he MET o each ac i i y and he daily minu es pe o med wi h he algo i hm de ined by he IPAQ Reliabili y S udy [48] o each ype o ac i i y: walking, o he mode a e ac i i y, and igo ous ac i i y. This sel - epo ed obse a ion a ied om 0 o 1560 MET min/day, wi h highe sco es indica ing mo e PA. As PA and ac ion con ol we e asked o he cu en day and he o he a iables we e asked o he nex day, he adjus men o 1day was conside ed on he da abase. A h ee-le el da abase s uc u e was designed, in which daily obse a ions (N = 338 in le el 1) we e nes ed in weeks (N = 58 in le el 2), which, in u n, we e nes ed in he sample pa icipan s (N = 9 in le el 3). A se o andom in e cep s and slope mul ile el eg ession analyses was hen es i- ma ed in Mplus 8 [49] using he Maximum Likelihood wi h Robus S anda d E o s me hod as sugges ed by Hox e al. [50] o p e en possible bias in he esiduals. The p edic o e ec s we e es ima ed o each phase o he HAPA model. Speci ically, o he mo i a ional phase, examina ion was unde aken o he associa ion o beha io al in en ion wi h sel -e icacy and social suppo (measu ed daily) and wi h isk awa eness and ou come expec ancies (bo h measu ed a weekly); o he oli ional phase, examina ion was done o he associa ion o he obse ed beha io s (km walked and sel - epo ed beha io ) wi h bo h daily-measu ed (beha - io al in en ion, planning, ac ion con ol, social suppo ) and weekly measu ed p edic o s ( eco e y sel -e icacy). Addi ionally, i was explo ed whe he beha io al in en ion (daily) and eco e y sel -e icacy (weekly) p edic ed beha - io al planning, as well as whe he hese a iables p edic ed ac ion con ol. Two mul ile el models we e es ima ed o each analy- sis. In model 1, he main e ec s o bo h daily and weekly measu ed p edic o s we e conside ed. Addi ionally, he ime was included as p edic o in he equa ion, aiming o con ol whe he he es ima ed e ec o p edic o s on he dependen a iables was due o a me e ime e ec [24]. In model 2, he in e ac ion e ms we e added be ween he ime and each p edic ing a iable, aiming o explo e whe he he es ima ed e ec s o each HAPA p edic o did no change o each ime poin obse ed, o whe he hey we e a iable along he imeline. The signi ican in e ac ion e ec s we e hen in e p e ed by plo ing he es ima ed e ec o he HAPA cons uc a each obse ed ime poin . Be o e es ima ing he mul ile el model, he p edic o s in each espec i e measu ed le el we e mean-cen e ed. Fu he mo e, he di e ences in he ime- a ying associa ions be ween weekdays and week- ends we e e i ied. Resul s In he p esen s udy, EMA comple ion a es we e high, wi h an a e age o 89% in all pa icipan s, anging om 40.5% (pa ien 9) o 100% (pa ien s 1, 4, 6, 7). These pa ame e s a e be e han he a e age ound in e iew s udies on his opic [40], which is 77%, wi h a es in indi idual s udies anging om 56 o 97.7%. The daily o weekly a iabili y o each cons uc a e ep esen ed in supplemen al ma e ial (S3 and S4), and he daily beha io al in en ions and obse ed and sel - epo ed PA beha io a e ep esen ed in Fig.1. Beha io al In en ion Table2 shows he es ima ed pa ame e s o he p edic ing a iables o beha io al in en ion. Resul s indica ed ha sel - e icacy was he only a iable ha eliably had an e ec in his ega d in model 1, meaning ha when pa icipan s el g ea e sel -e icacy, hei in en ion o engage in physical ac i i ies was also g ea e , whe he weekdays o weekends we e conside ed. This e ec was s a iona y, wi h model 2 showing ha he sel -e icacy × ime in e ac ion was no 782 In e na ional Jou nal o Beha io al Medicine (2023) 30:777–789 1 3 signi ican , meaning ha he ob ained e ec did no change a each ime poin obse ed. Impo an ly, model 2 showed an in e ac ion e ec be ween social suppo and ime. The decomposi ion o his in e ac ion indica ed ha he social suppo e ec was no associa ed wi h pa icipan s’ in en- ions o engage in physical ac i i ies in he i s days o he obse a ions. Howe e , by a ce ain poin in ime ( he 12 h day), he e ec o social suppo was high enough and became signi ican , meaning ha his con ibu ion did no occu immedia ely, bu ook 12days o i s e ec o mani es i sel in he PA (see Fig.2). Physical Ac i i y Beha io s Table3 p esen s he es ima ed pa ame e s o obse ed PA beha io s, bo h in daily dis ance co e ed (km) as measu ed by he pedome e and in sel - epo ed ac i i y engagemen . Model 1 esul s showed a signi ican e ec o planning, indi- ca ing ha pa icipan s walked mo e kilome e s and epo ed ha ing engaged in mo e PA on days when hey ga e mo e a en ion o planning hei ac i i ies. Model 2 demons a ed ha he e ec o planning did no change o each ime poin obse ed, as no signi ican planning × ime in e ac ion was ound. Impo an ly, a signi ican in e ac ion be ween eco e y sel -e icacy and ime was ound. These in e ac ions mean ha eco e y sel -e icacy p edic ed beha io al ac i i- ies di e en ly o e ime, so ha he s onge he eco e y sel -e icacy, he mo e kilome e s he pa icipan s walked, wi h hese e ec s becoming signi ican ly posi i e om he 17 h day o obse a ion (see Fig.3). Conside ing he au o eg essi e analysis, he esul s o beha io al in en ion, planning, and ac ion con ol did no change he p e ious indings. Fo he physical ac i i y beha io s, he au o eg essi e analysis iden i ied a nega- i e e ec , meaning ha he mo e pa icipan s walked he day be o e, he less hey walked on he p esen day. Fo he analysis o he weekdays/weekends, he e ec was posi i e, meaning pa icipan s walked longe dis ances a weekends. Planning Beha io s andAc ion Con ol Table4 p esen s he p edic o s o planning beha io and o ac ion con ol. Fo planning, model 1 indica ed ha in en- ion had a signi ican posi i e e ec , meaning ha on days when pa icipan s we e mo e in en on pe o ming physical ac i i ies, hey indica ed mo e planning o ca y ou hese ac i i ies, whe he PA on p e ious day, weekday, o week- end was conside ed. Model 2 showed ha his e ec did no Fig. 1 Daily dis ibu ion o beha io al in en ion, and obse ed and sel - epo ed physical ac i i y. No e. The igu e on he le shows he obse ed a iable (in en ion; PA dis ance and sel - epo ed PA) in each o he nine pa icipan s o e he days; he middle igu e shows he a e - ages o each obse ed a iable (in en ion; PA dis ance and sel - epo ed PA) o e he days o he g oup o women (all oge he and no indi idu- alized); and he igu e on he igh shows he dis ibu ion o equencies (and mean, SD, and o al N) o beha io s and in en ion le els o he se o obse a ions (N = 323) 783In e na ional Jou nal o Beha io al Medicine (2023) 30:777–789 1 3 change o each ime poin because he in e ac ion be ween in en ion and ime was no signi ican . Model 1 showed a eliable e ec o ime conce ning ac ion con ol, meaning ha ac ion con ol inc eased o e ime. Impo an ly, beha io al in en ion was also ound o ha e a posi i e e ec , in ha pa icipan s epo ed mo e ac ion con ol on days when hey we e mo e in en on pe - o ming physical ac i i ies. Model 2 showed ha his e ec did no change o each ime poin obse ed, as he e was no signi ican in e ac ion be ween he model p edic o s and ime. The model was also analyzed including con olling a i- ables (e.g., age, ma i al s a us, yea s om diagnosis), and he model es ima es did no change. Discussion I is demons a ed ha su i o s o b eas cance ha e high bene i s on being physically ac i e. The e o e, i is impo - an o es whe he he models ha explain PA hold ue o his popula ion in pa icula , be o e a emp ing o de elop in e en ions ha will be e ec i e in his popula ion. This s udy aimed o in es iga e how he cons uc s o he HAPA model a y o e ime and among hemsel es, as well as hei ela ionship wi h he in en ion o be ac i e and he a ia ion Table 2 Mul ile el eg ession es ima es o beha io al in en ion *p < .05; **p < .01; ***p < .001 Model 1 Model 2 b SE b SE In e cep –.040 .178 –.036 .176 Daily le el Sel -e icacy .774*** .134 .784** .119 Social suppo .035 .077 .024 .069 Time .001 .004 .002 .004 Au o eg ession .063 .049 .067 .046 Weekend –.039 .060 –.041 .057 Weekly le el Risk awa eness .020 .054 –.010 .043 Ou come expec ancies .008 .052 .054 .071 In e ac ions Sel -e icacy × ime –.006 .005 Social suppo × ime .004* .002 Va iance componen s Daily le el .381 .114 .371 .105 Weekly le el .001 .130 .001 .031 Indi idual le el .294 .300 .224 .156 In aclass co ela ion Weekly le el .001 .001 Indi idual le el .114 .107 Fig. 2 E ec o ime on he ela ionship be ween social suppo and in en ion o engage in physical ac i i y. The do ed lines ep esen he lowe and uppe con idence in e als a 95%. The e ical line indi- ca es he momen a which he e ec o social suppo on in en ion becomes signi ican 784 In e na ional Jou nal o Beha io al Medicine (2023) 30:777–789 1 3 in he le els o PA p ac iced, a he wi hin-pe son le el among women su i o s o b eas cance . In his g oup o pa icipan s, o bo h PA assessmen me hods used (di ec daily s ep coun and sel - epo ), he same esul s we e ound. Time e ec s in he a ia ion o cons uc s we e also examined. Daily luc ua ions in sel -e icacy we e ound o play a consis en ole in women’s in en ions o become mo e ac i e, as i was he case o social suppo , which inc eased a e he 12 h day o obse a ion. Weekly luc ua ions in isk awa eness and ou come expec ancies did no con ib- u e o in en ion building. Indeed, o he s udies pe o med a he wi hin-pe son [27] and be ween-pe son le el [19] concluded ha isk awa eness was no posi i ely associ- a ed wi h in en ions o be physically ac i e, and he e o e a gued o he assump ion ha isk pe cep ion is a a he dis al p edic o o in en ion [18]. Posi i e ou come expec an- cies we e no iden i ied as impo an o in en ion building o become ac i e, in con as o o he s udies pe o med a he in e pe sonal [19, 22] and in ape sonal le el [24, 27]. I could be ha he se e i y o b eas cance coun e ac ed he impo ance a ibu ed o posi i e ou come expec ancies, so ha hey we e no enough o change he beha io al in en- ion. In addi ion, pa icipan s ha e high le els o ou come expec ancies, so an expec a ion o a desi able ou come no longe allows weekly luc ua ions o a ec hei in en ions o is no longe ele an o weekly in en ion o ma ion. Con- side ing he associa ion o sel -e icacy o he in en ion o be ac i e, i was also iden i ied ha ime pe se did no change his e ec a his indi idual le el, meaning ha he inc ease in sel -e icacy was i sel ac ually necessa y o he in en- ion change owa ds a mo e ac i e li es yle. Such belie s in sel -e icacy should be conside ed in he u u e; hey can be de eloped by ocusing on pas success, by p o iding expe i- ences o mas e y in PA, and by modeling. The cu en s udy also sough o es whe he social suppo can be seen as an addi ional meaning ul p edic- o in he HAPA, since i has been shown o be in luen ial o PA beha io , ei he in he mo i a ional [19] o in he oli ional s age [20]. Indeed, social suppo has p e iously been iden i ied as an impo an de e minan o PA p ac ice o su i o s o b eas cance [51, 52]. In his s udy, i was Table 3 Mul ile el eg ession es ima es o physical ac i i y beha io s *p < .05; **p < .01; ***p < .001 Km Sel - epo Model 1 Model 2 Model 1 Model2 b SE b SE b SE b SE In e cep 5.165*** .669 5.126*** .623 2.664*** .310 2.758*** .284 Daily le el In en ion –.401 .327 –.471* .227 .069 .176 .030 .170 Planning .689*** .210 .692*** .148 .188* .076 .214** .076 Ac ion con ol .118 .142 .146 .144 –.005 .050 .029 .060 Social suppo –.081 .084 –.031 .117 –.061 .105 –.066 .125 Time .032 .018 .033 .138 .019 .015 .021 .016 Au o eg ession –.224* .095 –.226 .147 .090 .078 .076 .076 Weekend .773** .251 .772*** .238 .574*** .168 .527*** .004 Weekly le el Reco e y sel -e icacy .305 .225 .452* .212 .147 .199 .230 .206 In e ac ions In en ion × ime –.056 .140 –.018 .012 Planning × ime .044 .083 .011 .015 Ac ion con ol × ime .003 .093 .010 .010 Social suppo × ime –.002 .037 .010 .007 Rec sel -e icacy × ime .045** .015 .025*** .006 Va iance componen s Daily le el 4.772*** .945 4.524*** .741 3.617*** .601 3.595*** .602 Weekly le el 1.455 .540 1.285 1.098 .199 .333 .102 .457 Indi idual le el .412 .308 .184 .462 .399 .353 .301 .334 In aclass co ela ion Weekly le el .221 .216 .068 .068 Indi idual le el .056 .064 .079 .079 785In e na ional Jou nal o Beha io al Medicine (2023) 30:777–789 1 3 shown o be associa ed o mo i a ional bu no o oli ional cons uc s o PA beha io . When ime was conside ed, i was possible o e i y ha social suppo was associa ed wi h mo e in en ion o engage in PA a e he 12 h day o obse a ions. The suppo a ailable om he esea che a he beginning o he s udy may ha e obscu ed he sup- po gi en in he na u al en i onmen ; al e na i ely, na u al suppo may ha e only aken on impo ance in building up in en ions a e he esea che ’s in luence was absen o some ime. Addi ionally, social suppo has been iden i ied in he li e a u e as impo an in he oli ion phase o PA when sel -e icacy is lowe , helping o cope wi h he s ess- ul demands which come a e an in en ion is se and ac ing as a bu e [19]. Howe e , when sel -e icacy is highe , he Fig. 3 E ec o ime on he ela ionship be ween eco e y sel -e icacy on obse ed (uppe panel) and sel - epo ed (bo om panel) daily physi- cal ac i i y. The do ed lines ep esen he lowe and uppe con idence in e als a 95%. The e ical line indica es he momen a which he e ec o eco e y sel -e icacy on physical ac i i y becomes signi ican