Impact of a Father–Child, Community-Based Healthy Lifestyle Program: Qualitative Perspectives from the Family Unit

The Healthy Dads, Healthy Kids (HDHK) program was designed to help fathers with BMI ≥ 25 kg/m2 to lose weight and positively influence physical activity and dietary behaviors of their children. There is a need to better understand the broader impact of father-focused, healthy lifestyle programs from the perspectives of other family members. This qualitative study explored the impact of a HDHK by gathering insights from the family unit (fathers, mothers/partners and children). Fathers and children who participated in the HDHK dissemination trial from the Maitland local government area (New South Wales, Australia) (n = 33) and all mothers/partners of participating HDHK were invited to take part in this qualitative study. Eleven focus groups were undertaken with 25 fathers (41.9 ± 6.3 years, 32.4 ± 5.1 kg/m2), 15 mothers/partners’ (38.1 ± 6.6 years), and 41 children (51% male, 8.2 ± 2.1 years). Audio recordings were transcribed and analyzed by an independent researcher using a standard general inductive approach to qualitative analysis with thematic analysis applied. Three key themes emerged, demonstrating several personal and family program impacts. These included a positive impact on: (i) the father-child relationship, (ii) new family habits (e.g., lifestyle changes within the family unit) and (iii) fathers’ involvement and parenting practices (e.g., increase in fathers’ household responsibilities). Improving the knowledge and skills of fathers and children through evidence-based strategies may be a useful approach to strengthen their relationship, enhance parenting strategies, and optimize health behaviors. Notably, findings showed the changes made by the fathers and children positively impacted the wider family unit. First qualitative study to explore the impact of a father–child lifestyle program by gathering insights from the whole family unit. Fathers and children embraced program concepts to strengthen their relationship and optimize health behaviors. Fathers improved their parenting practices. Changes made by fathers and children positively impacted the wider family unit. First qualitative study to explore the impact of a father–child lifestyle program by gathering insights from the whole family unit. Fathers and children embraced program concepts to strengthen their relationship and optimize health behaviors. Fathers improved their parenting practices. Changes made by fathers and children positively impacted the wider family unit.


Introduction
Overweight and obesity are leading global public health challenges.Globally, 1.9 billion adults have a Body Mass Index (BMI) in the overweight range and 650 million are living with obesity (World Health Organization, 2021).Currently, Australia ranks within the top 10 of all developed countries in terms of obesity rates as a percentage of total adult population (OECD, 2020), with 67% of Australian adults living with overweight or obesity (Australian Institute of Health and Welfare, 2020).The high prevalence rates pose a considerable health and economic burden on individuals, families and nations (Tremmel et al., 2017).Specifically, obesity is associated with a range of non-communicable diseases including type 2 diabetes, cardiovascular disease, and certain cancers (Blüher, 2019).Further, the global economic impact of obesity was estimated to be US $2.0 trillion or 2.8% of the global gross domestic product (GDP) (Dobbs et al., 2014).In 2017, 18% of deaths worldwide were attributable to obesity-related diseases (Lin et al., 2020).
Obesity among males is especially concerning.In Australia, 75% of males live with overweight or obesity, compared to 60% of females.Further, adult men are more likely to have greater abdominal fat tissue than women (Wirth & Steinmetz, 1998), which independently increases metabolic syndrome and related cardio-metabolic risk (Després, 2006).Despite this, males remain less likely to perceive themselves as overweight, attempt weight loss or take part in weight loss programs (French et al., 1994;Lovejoy et al., 2009;Morgan et al., 2011c;Young et al., 2012).
The transition to fatherhood is recognized as a major social determinant of men's health (Garfield et al., 2006) and has been linked to men's weight status (Garfield et al., 2016).In a longitudinal, population-based study of 10,253 American men (Garfield et al., 2016), those who became a father during the study experienced an increase in BMI trajectory, whereas those who remained non-fathers experienced a relative decrease over the same period.These increases may have been driven in part by changes in lifestyle health behaviors as fathers responded to shifting priorities and time commitments (Pot & Keizer, 2016).To help fathers maintain a healthy weight, targeted lifestyle interventions that meet their unique preferences and values are needed.
Suboptimal lifestyle behaviors and increasing levels of obesity in fathers may also have flow on effects to their children.For example, a longitudinal study found obesity in fathers to be associated with a four-fold increase in the risk of obesity in both sons and daughters at 18 years of age (Burke et al., 2001).This is a major issue, as obesity becomes entrenched and around 55% of children who have obesity will still have obesity in adolescence, while 80% of adolescents with obesity go on to have obesity in adulthood (Simmonds et al., 2016).As such, there is an urgent need to understand and address this inter-generational health risk.
It is well-established that parents play a critical role in the development of positive health behaviors in children (Golan, 2006).Specifically, parents influence physical activity and dietary behaviors through their own behavior, attitude, modeling, parenting styles and child feeding practices (Davison & Birch, 2001;Lloyd et al., 2015;Sallis et al., 2000).However, relatively little empirical attention has examined the unique role of fathers.To date, fathers have been largely overlooked in both family-based programs targeting children's lifestyle behaviors (Morgan et al., 2017) and observational research investigating optimal parenting practices for children's physical activity and nutrition (Davison et al., 2016).Of interest, some of the available evidence suggests fathers' behaviors and parenting styles may be more influential on children's weight status than mothers (Stein et al., 2005;Wake et al., 2007).Potential reasoning is father's unique role in influencing physical activity, with fathers often more likely than mothers to engage in physical play (e.g., play wrestling) and to initiate co-participation in physical activity with their children (Beets et al., 2010;Morgan et al., 2020;Zahra et al., 2015).In addition, fathers tend to provide a better model of sports skill performance, due to their increased opportunities and reinforcement to practice sports skills throughout life (Hallal et al., 2012;Trost et al., 2002).
To improve the health and wellbeing of children, there may be utility in harnessing the father-child relationship as an innovative strategy to engage fathers in family-based, lifestyle interventions.The Healthy Dads, Healthy Kids (HDHK) program was the first lifestyle program to engage fathers to improve their children's physical activity and dietary behaviors.This program has previously demonstrated efficacy in a university-based research project delivered by qualified researchers (Morgan et al., 2011a) and demonstrated effectiveness in a community-based trial where trained facilitators delivered the program in local primary schools (Morgan et al., 2014).Overall, fathers and children improved their weight status, increased physical activity, and improved dietary behaviors.Importantly, a large dissemination trial of the program across a range of underserved communities revealed these results were mostly sustained at 12-month follow up (Morgan et al., 2019a).Despite these positive findings, we need to better understand the specific mechanisms of effect through which intervention fathers impacted on their children's physical activity, dietary behaviors, and weight status.Further, given scholars have suggested that fathers often bond with their children through physical play and lifestyle-related activities (Paquette & Dumont, 2013), it is important to explore whether participation in the program led to improvements in the father-child relationship or other family dynamics (Paquette & Dumont, 2013).Moreover, little is known about the ripple effect these changes may have on the wider family unit.Gathering insights from the whole family can help to improve overall understanding of these important questions.
Focus groups provide an appropriate and valuable method for obtaining comprehensive information about participants' experiences and opinions relating to a shared experience.However, only one study to date has qualitatively explored the impact of a father-child lifestyle intervention (Pollock et al., 2020).The study obtained perspectives from fathers who participated in the Dads And Daughters Exercising and Empowered' (DADEE) study (Morgan et al., 2019b(Morgan et al., , 2021) ) and identified holistic benefits of: daughters' social-emotional well-being, fathers' parenting skills, the father-daughter relationship, family relationship dynamics and knowledge and understanding of gender stereotypes and gender bias.These important findings were limited to perspectives from the fathers only and the program only targeted physical activity.Other qualitative studies which have explored the impact of family-based lifestyle interventions have provided some further insights (Twiddy et al., 2012;Watson et al., 2021).Views obtained from parents and children participating in the GOALS study in the UK (n = 39 children, n = 34 parents/carers, 15% fathers) identified learning as a family, being accountable and gradual realistic goal setting as factors that facilitated behavior change (Watson et al., 2021).Furthermore, insights from parents and children from the WATCH-IT program in the UK (n = 23 parent-child dyads, 22% fathers) found strong family support and a good relationship with staff to facilitate successful weight management (Twiddy et al., 2012).Despite these important insights, there was an under-representation of fathers and none of these studies obtained insights from non-participating partners to establish the wider impacts on the family.
To our knowledge, no previous study has explored the impact of a father-child lifestyle intervention by gathering perspectives from the whole family unit.Therefore, the aim of this study was to explore the broader impact of the HDHK program on the whole family (fathers, mothers and children), to help better understand how the intervention impacted on the families' physical activity, dietary behaviors and weight status.

Study Design
This was a qualitative study using focus groups.The University of Newcastle Human Research Ethics Committee approved the study (HREC-2010-0045).The conduct and reporting of this paper adhered to the guidelines outlined in the consolidated criteria for reporting qualitative research (COREQ) (Tong et al., 2007) see Supplementary File 1.

Participants and Recruitment
Participants were fathers and their children who had taken part in the 'Healthy Dads, Healthy Kids' (HDHK) dissemination program from the Maitland local government area (New South Wales) during 2012 who also consented to take part in a focus group discussion.Consenting mothers/ partners' of participants also took part in a focus group discussion.The focus groups were conducted immediately after the final session (session 8).
This project formed part of a larger mixed methods study.The full study methods have been described in detail elsewhere (Morgan et al., 2011a(Morgan et al., , b, 2014(Morgan et al., , 2019a)), and the objective of this current study builds on the overarching aim of the HDHK program which was to assess whether fathers can positively influence health behaviors of their children.Participants for this study were sampled from the HDHK dissemination trial, which ran between 2011-2013 (Morgan et al., 2019a).In this trial, the eligibility criteria included fathers who had a BMI greater than 25 kg/m 2 , had a primary school-aged child (typically aged between 5 and 12 years) and passed a pre-exercise screening questionnaire or provided a doctor's clearance.Fathers and their child(ren) were recruited (via school newsletters, social media, school presentations, local media release, fliers distributed to local communities and face-to-face interactions with parents of children attending the local schools) and assessed between 2011-2013 at local schools.
A written Focus Group Invitation, Participant Information Statement (which explained reasons for doing the research) and a Consent Form together with a reply-paid envelope were posted to all families that attended over 50% of the sessions and retained at the end of the program (n = 33).Verbal reminders were provided during the final session by facilitators to fathers and children.Those who returned a completed consent form for participation were contacted by phone to confirm the time and venue for the focus groups.SMS reminders were also sent prior to each focus group session.

The Healthy Dads, Healthy Kids (HDHK) Program
Full details of the program have been reported elsewhere (Morgan et al., 2011a(Morgan et al., , b, 2014(Morgan et al., , 2019a)).Briefly, the HDHK program was based on Social Cognitive Theory (SCT) (Bandura, 1986) and Family Systems Theory (FST) (Golan & Weizman, 2001) and aimed to assist fathers learn lifestyle-based weight loss strategies and become healthy role models to influence the lifestyle behaviors of their children.Specifically, the program used physical activity and healthy eating as an engagement medium to enhance quality one-on-one time between fathers and their children.Also, the program focused on an authoritative parenting style to facilitate better dietary and activity choices for children (Sleddens et al., 2011).
The 8-week intervention consisted of: eight consecutive weekly face-to-face group sessions (90 min each).There were four father-only sessions and four father-child sessions that focused on fundamental movement skills, rough and tumble play, health-related fitness, and fun and active household and backyard games.Fathers received additional resources to take home including i) a handbook which included a summary of the information from the face-toface sessions and additional background information and ii) Green slips at the end of each session which provided a homework activity (e.g., cooking meals with kids, family fundamental movements skills circuit).The children also received a handbook which included tasks to complete each week with dad (e.g., recipes to cook with dad).Although mothers did not attend any face-to-face sessions, fathers were encouraged to involve their partners using the activities and information detailed in the handbooks and Green slips to enhance social support of their children.
All face-to-face group sessions were delivered by two trained local Physical Education teachers who had completed a 6-8-hour facilitator training workshop (delivered by author PJM).The facilitator training covered; background information to the program, session-by-session content knowledge, and key tips to effectively manage and deliver the program.

Data Collection
A qualitative design using focus groups was selected as group interactions may elicit information and insights that are less accessible during individual interviews.This is particularly true in newly formed and transient groups such as these, where the group dynamic is likely to yield more rich, complex and honest conversations (Leask et al., 2001).
Fathers, mothers/partners, and children took part in separate focus groups consisting of between four and thirteen participants.These groups were held in a room adjacent to the usual HDHK session venue at a local primary school.The focus groups were conducted by five team members (including authors: AL, PJM, ATB, EC) who were trained in qualitative methods and involved in the intervention implementation.Of those who conducted focus groups, three were male and two were female.The occupation list and credentials at the time of the study included: one PhD student (with a Masters in Education), two chief investigators (Professor and PhD), one project officer and one project manager.During focus groups no one else was present besides the participants and interviewers.To support open and honest discussions and a diversity of opinions, the interviewers had a diverse skill set including; i) ability to build rapport and create a warm, supportive and comfortable environment where all feedback was valued, ii) a deep level of understanding of the program to enable more insightful conversations, iii) observation skills to recognize and respond to group dynamics and any changes to body language or demeanor, and iv) ability to remain impartial and maintaining verbal and non-verbal objectivity (Nyumba et al., 2018).The focus groups with fathers lasted on average 31 min (between 28 and 33 min), while the mums/ partners lasted an average of 35 min (between 23 and 46 min).The children's focus groups were shorter in duration, lasting 13 min on average (between 8 min and 18 min).During the focus groups, field notes were not taken.
The research team developed the discussion framework to facilitate discussion (Supplementary File 2).In the fathers' focus groups, questions were designed to explore the impact of the program on their physical activity and nutrition, as well as their parenting and family's health and lifestyle choices.The children's focus group questions were designed to elicit discussion about: any changes in their father as a result of the program, their perceptions of the physical activity sessions, overall likes and dislikes, and the impact of the program on the home environment (e.g., completing activities at home, impact on other family members etc.).Finally, the areas of enquiry in the mothers/ partners' focus groups centered around the father-child relationship, fathers' involvement and parenting practices and overall family dynamics.Whilst not reported in this manuscript, in all focus groups, researchers sought feedback on how the program could be improved, which informed future iterations of the program.

Analyses
The focus groups were audio recorded with the participants' consent and transcribed verbatim using an independent transcription company.Participants were given a pseudonym to ensure all remained de-identified.A qualitative analysis was conducted by an experienced, independent qualitative researcher (author VH) not involved in either study design, intervention implementation or data collection.An inductive thematic approach was applied which was aligned with the analytic process outlined elsewhere (Braun & Clarke, 2006).A thematic analysis was chosen due to its suitability for the descriptive aims of the research, and to allow for the experiences, meanings and the reality of participants to inform the thematic structure.NVivo Version 9 (QSR International Pty Ltd, 2010) was used to assist with the organizational aspects of the analysis.NVivo is a software program used for analysis of unstructured audio data.
Each data set for the three participant groups was initially analyzed separately using the following method.After an initial phase of data familiarization where insights, potential themes and relationships in the data were noted, a coding scheme was developed based on in vivo coding of the transcripts.This was an iterative process with the final coding scheme subsequently applied to the three datasets.The data relating to each code was reviewed and formed the basis for a semantic approach to theme generation across data from all three participant groups, in which themes were grounded within the explicit meaning of the data.All data falling under each theme and sub-theme were then reviewed again to ensure their fit under each theme, prompting minor changes to ensure that the overall thematic structure captured the entirety of the dataset.Each theme was defined and named and thematic summaries were developed which were supported by the integration of representative participant quotes.

Results
A total of 25 fathers, 15 mothers/partners, and 41 children participated in 11 focus groups.This represented a consent rate of 76% for fathers and 45% for mothers.The fathers had a mean age of 41.9 ± 6.3 years (range 31 to 54), a mean BMI of 32.4 ± 5.1 kg/m 2 , and most (n = 24, 96%) lived in areas of low to middle socio-economic status.The mothers had a mean age of 38.1 ± 6.6 years (range 29 to 48; four not reported).Of the 41 children, 21 (51%) were male and the mean age was 8.2 ± 2.1 years.Overall, 56% of the children had a BMI z-score which was classified as either overweight (+1 SD) or obesity (+2 SD), respectively.
Three key themes were constructed during the thematic analysis relating to a range of perceived personal and family impacts from program involvement (Table 1).These themes included a positive impact on: (i) the father-child relationship, (ii) new family habits (e.g., lifestyle changes within the family unit) and (iii) fathers' involvement and parenting practices (e.g., increase in fathers' household responsibilities).In addition, each key theme encompassed several subthemes as outlined below.

Father-Child Relationships
Most fathers, mothers and children made direct reference to father-child relationship as one of the most salient outcomes of the program.For fathers, it was often the main motivation for joining the program.The 'bonding benefit' was mentioned mostly by fathers who felt they had largely missed quality one-on-one interaction with their children due to work commitments, or because they had several other children at home."It's just the bonding, the one-on-one bonding with the kids is something I'd probably missed out on a fair bit.So that was really good for us and we've carried that on right through and I don't think that's something that will stop anytime soon."Dad "I feel a lot closer to the younger kids because I probably used to come home from work and sit down and it was dad's relax time, you know, that couple of hours after you come home from work.Where now I come home and the first thing I'll do is go to bat with them or have a wrestle or throw the ball or whatever.So for me, I'm a lot -I feel I'm a lot closer in the last maybe four to six weeks to my youngest three kids."Dad Similarly, many children perceived the program as a chance to spend some much needed quality one-on-one time with their dads, by engaging in fun and game-filled activities which were felt to benefit them both."Getting to know each other better" was a phrase commonly used.The majority of children perceived their dad as equally having gained enjoyment from spending more time with them during the program; "I think he enjoyed spending time with me" and "You get to have fun with your dad and you never want to stop."In addition, half of the children felt that their fathers were now spending more time with them: "Now he doesn't like to be on the computer and looks for news every single time he comes from work, but now he's like playing with us most of the time."Child "At home after he gets home from work he just goes straight -he gets me and my sisters and he says, come on Harry, let's go jump on the trampoline and pass the ball.But when he didn't come to Healthy Dads Healthy Kids, he didn't do that."Child Most mothers reported a noticeable increase in the time fathers were spending with their kids, as well as an improvement in their relationship.Most perceived this to be one of the most important outcomes of the HDHK program, because of the usual scarcity of such dad-kid bonding opportunities, with this being particularly the case for fatherdaughter relationships, where the program had been felt to provide a common ground for interaction and bonding.
"I find him with the kids instead of sitting down watching TV or playing a game or something like that."Mum "I think the kids have really, really enjoyed doing this with their dad.I think it's been really good for them and to go out and leave me because that just doesn't happen ever.I'm taking one of them or all of or it just never happens that he leaves the house with all three kids and I'm in the house on my own.It's such a rare thing so I think that's been really good for their relationships."Mum

New Family Habits
Most fathers commented on the positive way in which their children involved in the program had embraced the concepts, from food changes to physical activities, and carried those through to the home environment.Specifically, the children continually motivated their dads to participate, bringing about lifestyle changes within the family unit above what would take place with only the parent attending.
"Well for me, it started off just as a more one-on-one time with [child] because of -with four -I'm backwards and forwards from work.Basically, he knew that every Wednesday night he had me for this period of time for himself.Then that's actually rolled on to all the kids because they're interactive as far as 'let's do the courses' or 'let's do the obstacle challenges' or whatever else is now rolled in through the other three as well."Dad For many, the games learnt through the program were becoming part of family routine (e.g., "sock wrestle" or "backyard obstacle course").Many fathers talked about how their child would now often invite them to join in physical activities and physical play.This was corroborated by the children; "We set a little circuit up at home and they always come and say, time to do the circuit dad."Dad "My daughter quite regularly now wants to have sock wrestles and stuff when we go home" Dad "I find the kids come to me a lot more to play and do things now.Like they would just play together, now they actually say dad, let's go out, we're kicking a ball or dad, we're going to go jump on the trampoline and yeah, so it gets me up and motivated too" Dad "Ever since we've come here, we've made sure we've taken care of dad and made him a healthier lunch and played more games with him than we used to."Child Furthermore, most fathers talked of simple but fundamental changes to family choices, such as eating dinner without the TV on, going for regular walks or other physical activity as a whole family.Many of the fathers and mothers talked of the family having increased focus on, and motivation to, engage in healthy behaviors; as well as benefits in terms of a newly established patterns and awareness of healthy and unhealthy food and nutrition."It's made a big difference to our family's nutrition.I think we spend a lot more time wandering in [the supermarket] at the fruit and veg section, getting the nice things.They think, oh what can we get to go with this salad instead of going to the meat section or the bakery section and said, ah we'll just grab this to go with that.I think the main focus now is the salad and the vegetables which is from this program."Dad "I like the fact that my husband hasn't eaten a family block of chocolate most nights of the week.But I hate the fact that I can't do it either.So we're more aware of what we have in the household at the moment, as far as food goes.So therefore if you do feel like that naughty snack, there's not an option to have it.It's got to be a healthy one at the moment.It's been really good."Mum Many fathers talked about the strategies and knowledge they had gained to enable improved planning of their diet such as making healthier lunch choices, opting for healthier take-away options, reading food labels as well as a more astute understanding of, and attention to, the intake-output balance (e.g., daily kilojoule [kJ] requirements to maintain a healthy weight).For example; "…at the end of the day I sort of had this little picture in my head of hey I'm 9500 kJ [2270 calories] today and I've actually had 6500 kJ [1553 calories], you know those sorts of things."Dad Other new strategies commonly adopted were reducing portion size, "surfing the urge" (tuning into hunger cues and avoiding unnecessary snacking), choosing healthier snacks, and limiting screen time for themselves and their children.Furthermore, most fathers and mothers talked of engaging in opportunistic physical activity, which was perceived to be largely initiated by the fathers (e.g., getting up earlier to go for a walk or playing with kids after work).
"My wife and I and our young fellow will go for a walk and for that hour that we're walking, like, we're talking and doing stuff and that's not focussing on a screen and we're finding that like every Sunday morning now it's a regular thing, we just go for a big long walk somewhere and couple of afternoons we take the dogs for a walk and it's just stuff that we didn't do before as a little unit.It's really good."Dad "It's been the physical activities.My husband will reluctantly come for a walk with us before whereas now it's 'let's go for a walk'."Mum The notable changes in the fathers were clearly observed by the children.The majority of children perceived their fathers as generally more active (e.g., "he's been doing lots of exercise" and "he's a lot fitter"), replacing screen time with physical activity time ("my dad has stopped being so focused on TV and the computer and the iPad and he's come out and he's played with us") and eating more healthy food ("he eats healthy and it's good"), while others made direct reference to their father having lost weight: "Before dad came to Healthy Dads, Healthy Kids you could see a bit of a belly under his shirt but since he's come back he is much changed and he is much healthier and can run better."Child "He's lost some weight and he has muscles".Child "His body shape's changed and he's lost weight and he also gets to know some activities that he can do to exercise now."Child While some mothers reported their partners' new enthusiasm relating to diet and exercise to be somewhat overwhelming, the majority reported the new 'dad as a health instructor' as a very positive change for the family.
"Definitely my husband tends to be a bit more aware of what's going on around him now that he's taking more interest in the program and what the program is teaching him.He's trying to teach that to all of us as well, so he's become the instructor himself.Yeah, we try and humour him as much as we can and go along with it."Mum While many mothers reported having attempted to initiate changes to family diet and routines in the past, they felt that the information and initiatives provided through the HDHK program had been more readily accepted and taken on board by their partners and children, due to it coming from an "outside authority".
"I think sometimes if all the information comes from me, it's not always accepted or that I'm the 'know it all'.So, if it comes from somebody else, in research and comes through them, then he's a bit more accepting of it.So yes, I did like that he took on that responsibility and it wasn't mine."Mum For some fathers, the program had increased quality time spent together which had effects extending to the entire family unit and facilitated family bonding… "it definitely brought the family closer".

Fathers' Involvement and Parenting Practices
Most mums talked of their partners having taken on more chores and other household responsibilities since their involvement in the program.In particular, the fathers had been instrumental in implementing new household rules relating to screen time and improved family awareness relating to nutrition and healthy eating.For many, these new attitudes had positively changed the dynamics of the household.Most mothers voiced their appreciation of their partners' new involvement and interest in family health and diet.This had been particularly evident around meal planning, food shopping, packing kids' and fathers' lunches etc where responsibilities in the past, had fallen on the mothers.The fathers'' newfound skills such as assessing the nutritional value of foods selected was felt as a welcome change.Some mums also perceived the program as having facilitated an overall increase in their partners' involvement in parenting.A few perceived the main outcome of the program being the fathers' renewed enthusiasm to make a difference.
"So much of the food and healthy eating responsibility is the mother's responsibility and the dads aren't always willing partners coming along with it.It's nice to have the dads reading labels and realising what they're putting in their mouths.So I love that aspect of it."Mum The fathers' increased involvement and positive influence on parenting were also mentioned by some children, particularly around their fathers' becoming more helpful around the home ("he's been helping around the house more") and generally being in a better mood ("he has changed because he has got nicer").
Most mums indicated that the program had given their partners a better understanding of the issues faced by mothers, ensuring that they both now were standing united and "being on the same page" when it came to family choices.
"As a mother, a lot of the things that he was coming home and saying and sharing with me, sort of had an idea anyway.Because you always put your children's nutrition first and what not.But with having him on board, it was reinforcing those behaviours that need to be there, as far as eating and things like that go.As far as computer time, television time, and just exercise in general.So it was good to have him on board, him informed and on the same page."Mum "The kids now know if you ask mum or dad, the answer is going to be the same…" Mum

Discussion
This paper aimed to qualitatively explore the impact of a father-child, community-based healthy lifestyle program (Healthy Dads, Healthy Kids) on the whole family unit (fathers, mothers/ partners and children) and from the whole family's perspective.Three key themes emerged, demonstrating several personal and family impacts from program involvement.These included a positive impact on: (i) the father-child relationship, (ii) new family habits (e.g., lifestyle changes within the family unit) and (iii) fathers' involvement and parenting practices (e.g., increase in fathers' household responsibilities).These important findings build on the previously established health benefits of the HDHK program (Morgan et al., 2011a(Morgan et al., , 2014) ) and highlight the broader benefits to the family unit.

Father-Child Relationships
The HDHK program had a profound impact on the fatherchild relationship, with all family members identifying this as one of the most salient outcomes of the program.
Fostering these relationships through co-physical activity was a key aspect of HDHK.This finding aligns with another qualitative study among fathers and adult daughters who both identified co-physical activity as the single most important turning point in the development of their relationship during childhood (Barrett & Morman, 2013).Further, another qualitative study that explored impact of a father-daughter, physical activity program found that fathers felt a physically and emotionally closer bond with their daughters due to quality time spent being active together (Pollock et al., 2020).Evidence from sociology, supports these findings, with Paquette describing the father-child bond as an "activation relationship" that is commonly developed through co-physical activity and stimulating, vigorous, and unpredictable physical play (Paquette, 2004;Paquette & Dumont, 2013).Regular co-physical activity and rough and tumble play with children provides an opportunity for fathers to spend time with their children to bond and develop shared interests (Neshteruk et al., 2020).These interactions can lead to holistic benefits for the family and especially children, including positive physical, psychological, social-emotional, educational, developmental and family cohesion outcomes (Allport et al., 2018;Wilson & Prior, 2011;Yogman et al., 2016;Young & Morgan, 2017).This type of 'rough-and-tumble' play was a key component of HDHK, with fathers and children undertaking this in the group-based practical sessions.Further encouragement, ideas and support was provided to continue cophysical activity and rough and tumble play at home using the activity handbook and Greenslip tasks.

New Family Habits
Fathers and children embraced key program concepts and influenced positive lifestyle behaviors among each other and the wider family unit.While the quantitative improvements on lifestyle behaviors have been confirmed elsewhere (Morgan et al., 2011a(Morgan et al., , 2014)), these findings help to provide context as to why and how these changes occurred.
The HDHK program's focus on 'reciprocal reinforcement' appeared to be a valuable strategy for optimizing the lifestyle habits of participating families.For example, in addition to encouraging fathers to be positive role models for their children, the children were also responsible in driving many home-based activities and encouraged to motivate their fathers to be more active and to eat healthier.The qualitative findings confirm that this concept of reciprocal reinforcement (Bandura, 1978;Golan & Weizman, 2001) was embraced, with many mum's affirming dads to be the initiators of healthy habits, while many dad's talked of children inviting them to initiate the healthy habits (e.g., "time to do the circuit dad" and "what can we get to go with this salad?").This suggests that fathers have an important influence on the lifestyle habits of their children and vice versa.The bi-directional impact between father and child physical activity and diet has been reported elsewhere.Specifically, a review of eight studies identified a modest, positive association between father and child activity levels (Neshteruk et al., 2017), while moderate to strong positive associations have been identified for father-child dietary intake (Vollmer et al., 2015;Walsh et al., 2015).
In terms of the wider changes to the whole family, it appears fathers were seen as the initiators of change at home.This finding is congruent with other qualitative research, where fathers were described as the family's 'physical activity leaders' responsible for engaging children in physical activities at home and in the community, and were more likely to initiate co-physical activity at home (Zahra et al., 2015).The influence on the wider families' lifestyle habits is rationalized in the Family Systems Theory, which suggests that the family is a complex and interactive social system where all members' needs and experiences affect the others (Golan & Weizman, 2001).It is possible that fathers and children embraced the HDHK program concepts and carried these through to the home environment to influence other family members.Then, each family member influenced the other reciprocally, directly, and indirectly (Morgan et al., 2020).
The transition to fatherhood is a transformative process for many men (Genesoni & Tallandini, 2009), while it is often described as joyful and fulfilling, it can also introduce new challenges which can impact on men's physical and psychological well-being (Durette et al., 2011;Morgan et al., 2020).In particular, research has shown physical activity levels to decline during early fatherhood (Hull et al., 2010;Pot & Keizer, 2016) which can have flow-on effects for their children (Morgan et al., 2020).Further, emerging literature has shown entry to fatherhood to be associated with long-term weight gain (Lo et al., 2021), and while changes in diet are likely to play a role in this perinatal weight change, few studies have examined changes in nutritional intake among new fathers (Saxbe et al., 2018).Given these challenges, the responses from the children in this current study which affirm fathers to be "more active", "healthier" and "spend more time with them" further highlight the positive impact of the HDHK program.These findings align with previous qualitative research which found new fathers successfully maintained pre-child physical activity levels to be motivated by; i) co-physical activity with children, ii) becoming a physically active role model, and iii) benefitting the health of their family (Mailey et al., 2014).As such, targeting these motivations as was the case in HDHK, may help to engage fathers in programs that can offset the decline in physical activity and associated weight gain typically observed during early fatherhood.

Fathers' Involvement and Parenting Practices
Traditional parenting roles (i.e., mothers being primary caretaker) have changed and fathers are now spending more time with children than ever before (Morgan et al., 2020;Parker & Wang, 2013).Despite this, previous qualitative research has shown that some fathers could benefit from additional training and skills to enhance their parenting effectiveness (Lindsay et al., 2018;Sicouri et al., 2018;Walsh et al., 2017).Given this, the findings from this current study are particularly notable.Mothers' commonly spoke of the noticeable impact that the HDHK program had on improving fathers' understanding, skills, and approaches to parenting.HDHK educated fathers on using an authoritative parenting style (e.g., a combination of high parental control and positive stimuli to the child's autonomy, including nurturing/warmth, rational communication and receptiveness (Lavrič & Naterer, 2020)) as evidence has shown a positive relationship between this parenting style with physical activity (Davids & Roman, 2014) and making healthy dietary habits in children (Kiefner-Burmeister & Hinman, 2020).
Mothers' commonly highlighted that fathers had taken on more household responsibilities, had a better understanding of the issues that they faced and were now: "on the same page" when making family choices.This is an important finding because co-parenting (i.e., ways that parents work together in their roles as parents) is linked to several beneficial parent-child outcomes (Feinberg, 2002) and is a key concept of overall family wellbeing (Eira Nunes et al., 2021).A recent systematic review and metaanalysis of 23 co-parenting programs established improvements to parents' well-being and couple relationship (Eira Nunes et al., 2021).In addition, co-parenting has been considered a mediator of other influences (e.g., individual parent characteristics, work pressure and marital conflict) (Feinberg, 2002).Co-parenting quality has also been linked to improved parent-child relationship (Pedro et al., 2012) and healthy development among children, including improved social-emotional well-being, social competence (Dopkins Stright & Neitzel, 2003;McHale et al., 1999;Teubert & Pinquart, 2010) and a reduction in risk of externalizing and internalizing problem behaviors for children (Cowan et al., 2008).

Strengths and Limitations
The results of this novel qualitative study are strengthened by the collection of in-depth responses from mothers/partners', fathers and children to understand the broader impacts of the HDHK program on the whole family unit.Further, to improve credibility of the data, the analysis was conducted by an independent researcher with considerable expertise in qualitative methods (author VH).However, the study has limitations.Firstly, data were collected approximately 10 years prior to writing this manuscript.It is unclear if newer data would have produced different results given the generational differences in parenting practices (Garcia et al., 2020) and the impact of the COVID-19 pandemic on lifestyle behaviors in children (Paterson et al., 2021) and adults (Chew & Lopez, 2021).However, data from Australia's physical activity report card for children have shown consistent screen time and physical activity levels between 2014 to 2022 (Active Healthy Kids Australia, 2022).Similar trends have been evident among national dietary intake data in Australian children and adults (Australian Institute of Health and Welfare, 2018Welfare, , 2019Welfare, , 2022)).Therefore, the rationale and findings from this current study still has important implications.Findings are also limited by the time point when data were collected (after the last HDHK session).This was done to enhance response rate but only provides insights into short term impacts of the program.Although the qualitative longterm impacts could not be determined within this study, it is evident from a quantitative evaluation of the HDHK program that improvements to lifestyle behaviors (weight, BMI z-score, physical activity, dietary behaviors) were sustained at 12-months among fathers and children (Morgan et al., 2019b).Furthermore, focus groups were moderated by members of the research team who were involved in the study design and/or delivery.Consequently, the relationships participants had developed with the researchers may have affected their responses in the focus groups.However, this limitation was balanced against the value of using moderators who had a deep level of understanding of the program and could enable more insightful conversations.Also, interviewees (especially the children) may have felt more comfortable in discussions with a known person.As mentioned previously, an independent researcher conducted the analysis to reduce the impact of this potential bias.In addition, there was no opportunity for participants to comment and/or correct transcripts or provide feedback on findings.The children's focus groups were shorter in duration (lasting 13 min on average) which may be insufficient time to capture the full depth and breadth of the topic.However, a previous review on focus group research have confirmed the need for shorter interviews among children, and the overall length depends on several factors such as: the subject chosen, the skill of the moderator, and the time of day (Heary & Hennessy, 2002).While there is no set rule for appropriate length of focus groups among children, the approach for this current study was consistent with what has been suggested elsewhere (Adler et al., 2019), which was to conduct three or four focus groups and then assess whether saturation has been reached.After four focus groups with children, increasing repetitiveness or redundancy in the data (data saturation) was observed, and the generation of new codes ceased (inductive thematic saturation).Hence, we were confident that a reasonable range of varying participant experiences had been collected to address the aims of the study.Finally, as the mothers were not involved in the HDHK program, demographic data were not collected for this group.

Conclusions
This study builds on the previously established health benefits of a father-child, community-based healthy lifestyle program (Healthy Dads, Healthy Kids) and highlights the broader benefits of the program to the family unit.Despite the reported benefits of involving fathers in family-based lifestyle programs, they have been largely overlooked.Placing a greater emphasis on intervention benefits on the whole family unit and enriched father-child relationship may be an effective way to recruit and engage fathers into future family-based interventions.Furthermore, the evidence-based strategies implemented in the HDHK program can inform design and delivery of more effective father-child lifestyle programs, with potential to achieve holistic benefits to health, parenting practices and enhanced family relationships.

Table 1
Fathers, mothers/partners' and children's perceived impacts of involvement in the HDHK program