Children and adolescents with obesity can be motivated to engage with obesity health services that focus on diet or physical activity interventions because of the perceived benefits of such activities.

Children and adolescents with obesity reported being motivated by several factors to engage with the interventions: not only the expected and hoped-for benefits of weight loss [27,32], but also other benefits, such as preventing health sequelae, being socially accepted, and building self confidence and self-esteem [23,25,27,28,31,32]. Adolescents highlighted that their desire for weight loss was partly driven by wanting to take responsibility/ have agency for their condition and to follow a healthy lifestyle [23]. Some children and adolescents also reported being motivated by observing the achievements of other children and adolescents who have engaged, or are engaging, with such activities [27], as well as recognising their own success [23,31]. Other factors that particularly motivated adolescents to engage with physical activity include being able to attend a gym [23,24]. Benefits differ by gender, with girls hoping for improvements in weight loss and physical appearance, while boys wanted to build muscle and become good at sport [26].

This finding is based on nine reviews [23–29,31,32] (with 180 included primary qualitative studies). Most of the studies had minor or moderate concerns regarding methodological limitations but the data richness score varied amongst the studies.

Children and adolescents with obesity can view the idea of diet or physical activity interventions negatively, and question the value of such activities.

Some children and adolescents with obesity viewed the idea of dietary intervention, exercise or physical activity interventions negatively and questioned the value of such activities. However, reasons for questioning the value of these interventions differed between dietary interventions and physical activity interventions. Some children and adolescents with obesity did not engage in physical activity as they gained no pleasure from exercise, “I gained weight gradually every year, like five or ten pounds. PE didn’t do anything for me” [24]; while some reported that even the idea of such activities occasioned a negative self-image because they were worried about not being able to do the activities due to their weight or a lack of the necessary skills, “I think the weight caused [failure in physical education class]. Because I was overweight I didn’t want to make an effort. I didn’t want to try because I knew I wouldn’t be good at it” [24,26,31,32]. Where the impact of dietary interventions was small and unfavourable with intangible benefit, this reduced adolescents and children’s desire to sustain dietary change [26,27].

Some participants reported difficulties in engaging with the intervention during periods of increased stress, the problems of coping with hunger, and a dislike of the lifestyle changes required to maintain weight [27].

This finding is based on six reviews [19,24,26,27,31,32] (with 108 included primary qualitative studies), with minor or moderate concerns regarding methodological limitations, but variable richness data.

Individual children, adolescents and their families have many other commitments; such competing priorities can represent a problem when it comes to thinking about or engaging in diet and physical activity interventions.

Children and adolescents with obesity reported that they had fewer opportunities for structured activity when engaging with exercise and physical activities [24,27], in part because as they became older, they became more autonomous and did less with family and at school; they increasingly just engaged in sedentary activities [27]. They also described having other commitments, such as school work and seeing friends [24] or just lacked the time and energy for such activities, “...if I exercise, I have to exercise for a long time to burn calories, and I think this will make me very tired” [27]. Other family members also reported competing priorities of work and family, which reduced the time available for such activities [24]. There was also a reported gender and cultural element: African-American adolescent girls reported that physical activity were simply not seen as a priority: “[Girls are] not interested in working like real hard doing all that exercise stuff. Some of them like – like girls they don’t like to sweat and get their hair messed up...They think like they do the wrong thing, they break their nails, it’s a crisis.” [19].

In terms of implementing dietary interventions, parents of children and adolescents with obesity reported that due to their multiple commitments, busy schedule and lack of time, it was difficult to make time for discussions about health and diet with their children [27,29], to implement healthy eating habits [28] or to prepare meals in accordance with the intervention [24,28].

This finding is based on five reviews [19,24,27–29] (with 99 included primary qualitative studies). The methodological quality and the richness of the data varied amongst the studies.

Family involvement and support is important if children and adolescents with obesity are to engage with diet or physical activity interventions.

Children and adolescents with obesity reported that they liked parents and family to be involved as much as possible in their dietary management and physical activities; having family actively involved with the intervention (exercise or diet) acted as a motivator to engage and continue engagement with such interventions: “I don’t really go to gyms. At my mom’s house, I have a basketball court. When I work out and I do stuff, I usually like to do it with my cousin or by myself... because then I don’t have to prove nothing to nobody. I do what I can do”. [24,25,31].

Parents also reported valuing the intervention activities such as physical exercises and/ or diet management [25]. Some children and adolescents – of both genders – reported that they valued the support and involvement of mothers the most. The types of support adolescents preferred from their families differed. Some adolescents with obesity reported that they preferred emotional, motivational or verbal support from family members, including parents and siblings [24,28,32]. Others preferred active participation in the intervention by family members: “having my mom with me really motivates me” [24,28]. Children and adolescents reported that the failure of parents and siblings to engage with the intervention, or their apparent lack of interest, understanding or knowledge about the need and value of such activities adversely affected whether they were likely to participate, “there was a time when my daughter would say, I don’t want to go,’cause they’re telling me I can’t eat this and can’t eat that. And I go, No we’ll go,’cause they’re telling me the same thing. When she saw it was difficult for me too and we started getting into a routine, she started wanting to go” [31]. Some parents had cultural beliefs suggesting that thinness is a sign of sickness and convinced adolescents that body weight is not an important negative indicator of health [28]. The conflicting opinions and approaches to healthy lifestyle from parents and other family members could also be confusing for children and adolescents, preventing them from engaging successfully with the intervention [29].

Some children and adolescents also reported that parents were important role models: adolescents considered it frustrating when parents failed to model appropriate behaviours, “How can I tell her “this is what you need to do” if she’s not seeing me do it” [24]. Some adolescents also reported that personal norms, such as family members themselves living with their own obesity, made it more difficult for them to engage with the intervention [19]. Conversely, it was reported that if a family had an active lifestyle, then this made participation with the intervention much easier [25].

Some children and adolescents reported how they depended on their parents either for access to, or to provide the means for participating in, certain exercise and physical activity interventions, such as providing transport to gyms [24,27]. Children and adolescents may also rely on their parents to purchase, prepare and provide intervention-specific food choices [24,28]. Hence, some adolescents described a lack of control and influence over their diet: “If you’re just having something for dinner and it’s... healthy or not healthy... it’s not like you can change it necessarily because if that’s what... is made at home, then that’s what you’re going to eat” [24].

By contrast, others reported that being away from home and their parents made it difficult for them to maintain healthy lifestyle.

This finding is based on eleven reviews [19,21,23–29,31,32] (with 206 included primary qualitative studies). Most of the studies had minor or moderate concerns regarding methodological limitations, but concerns regarding richness varied.

Health worker support is important if children and adolescents are to engage with diet or physical activity interventions.

Children and adolescents with obesity reported that the failure of health workers delivering the intervention, to act as role models [26], or to support children and adolescents with structured advice on diet, nutrition, exercise and physical activities, adversely affected their participation in interventions: “..the problem was not being taken seriously, and felt rejected when asking for help” [24,31]. Conversely, sensitive and supportive health workers offered motivation for some children and adolescents: “I went to you know like my GP a couple of times to try and get advice on …what I should do … [was advised to] be mindful of what the intake was and perhaps to, to exercise regularly you know with, either with friends or you know try and get support you know. So that did help a lot.”. [27].

Adolescents and their parents valued health workers who were experienced, knowledgeable and who specialised in supporting children with obesity [23]. Parents respond best to health workers who are empathetic, direct and clear [26]. Parents viewed good staff-participant relationships as vital for continued attendance voicing their intention to drop out of treatment if staff lack experience, enthusiasm or group management skills. Some adolescents also reported that education and physical exercise professionals, rather than supporting those with obesity, contributed to stigmatization, for example, by punishing the whole class for the slowest person or highlighting their weight as an issue [19].

This finding is based on eight reviews [19,23,24,26,27,29–31] (with 144 included primary qualitative studies). Most of the studies had minor concerns regarding methodological limitations, but variable concerns regarding richness.

Peer involvement and social support is important if children and adolescents are to engage with diet or physical activity interventions.

Children and adolescents with obesity reported that social support and reaction from friends and peers was highly influential when deciding to engage with, or reject, dietary management or physical activity interventions. Adolescents in one study described being around their peers as a security blanket, allowing them to feel comfortable and confident: “your friend[s] are there, and they can motivate you to do better, too’. [23]. Having peer support gave them a sense of belonging by allowing them to talk to others in a similar situation to them, sharing their struggles and issues and this motivated them to take part in the interventions, “I found them fun because I was surrounded by different people who were in the situation that I was in.” [23,32]. In particular, group sessions were described as having a positive impact on children’s confidence and viewed as fundamental to both initiation and maintenance of health behaviour changes [23,25,29]. Adolescents also reported that peers needed to act as role models [19]. Conversely, the failure of peers to support them in their engagement with healthy diet or physical activity adversely affected the likelihood of their participation with interventions [19,24,31,32] The personal norms of peers could even contribute to the stigmatizing of exercise and physical activities: “In the gym, they laugh and talk behind my back,” and, “It hurts me when they say ‘hey there, fat kid.’ I try to ignore them, but it does not stop” [24]. Concerns about stigmatization by peers – either due to the physical activities involved or clothing required, especially for girls – was reported by adolescents as a barrier to engaging with such activities [19,31].

This finding is based on nine reviews [19,21,23–25,27,29,31,32] (with 113 included primary qualitative studies). Most studies had minor or moderate concerns regarding methodological limitations, but concerns regarding richness varied.

Physical resources at school (spaces, equipment and facilities) need to be accessible and appropriate if children and adolescents are to engage with physical activity interventions.

Adolescents with obesity reported that they needed their schools to have accessible and appropriate facilities, both during and after school, if they were to be able to engage with physical activity interventions, and to maintain exercise activities after the programme has ended [19,27,31].

Some adolescent girls with obesity also pointed out that provision of appropriate facilities includes changing room and exercise areas where they do not feel ‘on display’: “...the worst bit was getting changed and getting into the uniform for PE,...” [19,31]. The non-availability of preferred activities was also reported by some adolescents to be an issue: caps on numbers and certain activities only being offered at particular times of the year prevented engagement in preferred exercise interventions [19].

This finding is based on four reviews [19,23,27,31] (with 70 included primary qualitative studies). There were minor to moderate concerns regarding methodological limitations and minor to moderate concerns regarding richness.

Physical resources at home and in the community (safe spaces to play and exercise) need to be accessible and appropriate if children and adolescents are to engage with physical activity interventions.

Some children and adolescents with obesity reported that they wanted access to physical spaces and facilities both at home [24] and in their community [24,27] to support their engagement with exercise or physical activity interventions, and that such physical spaces should be local and safe, “I need someone to walk with me. My mom doesn’t want me walking around by myself. She says that she doesn’t trust the guys in the neighborhood” [24,31].

This finding is based on three reviews [24,27,31] (with 42 included primary qualitative studies). There were minor to moderate concerns regarding methodological limitations but moderate to serious concerns about richness.

If the weather conditions are inappropriate for the type of planned physical activity, then children and adolescents may not be motivated to engage in physical activity.

Children and adolescents with obesity report concerns about how excessively hot or cold weather limits their opportunities to engage with exercise or physical activity interventions [19,24].

This finding is based on two reviews [19,24] (with 26 included primary qualitative studies); there were minor concerns regarding methodological limitations, but serious concerns about richness.

Resource, programme and facilities at school, home and in the community need to be accessible for children, adolescents and their families to engage with dietary interventions.

Adolescents with obesity reported that limited access to intervention-specific food options, as well as facilities that promote healthy eating within school and within the broader social and cultural environment [20,27], prevented them from engaging with dietary management interventions [28]. By contrast, easy access to restaurants and food outlets attracted families to consume ‘unhealthy’ food [28]. Moreover clinic hours and scheduling conflicts such as school holidays and after-school activities, clinic location and a lack of transport to programme location and length of visit were reported reasons for families not engaging with the dietary intervention programmes [25,29,30].

This finding is based on six reviews [20,25,27–30] (with 98 included primary qualitative studies). The methodological quality and the richness of the data varied between the reviews.

The types of diets or physical activities available are important; they should be social, fun, informal and regular.

Parents preferred to enrol their children in programmes that focused on lifestyle (i.e., incorporated nutrition, physical activity and behavioural components) over programs with other primary focuses, such as those centered mainly on medication, clinical treatment, or short-term weight loss interventions. They favoured programmes that took a holistic approach to weight management rather than those that focused on weight loss or dieting alone [25]. Adolescents expressed preference for group/team activities and programmes with peers and friends: “the team games were good. Boost their confidence to join in with their mates. Cause some of these kids are really isolated so they need team sports to encourage them to join in” [21]. Some adolescents complained the absence of support from peers when exercising [19], although some adolescents also reported that going to the gym by themselves was best [23]. They wanted exercise interventions to be available regularly and frequently, rather than being accessible only intermittently [27] and expressed a greater preference for physical activity interventions over dietary interventions [26].

Children, adolescents and their caregivers also reported that they preferred obesity interventions that were highly practical [21], but also informal and fun: “It wasn’t just like ‘you need to do more exercise and you need to eat better’ – it actually taught us like how to” [21,23,24,26]. They did not like exercise and physical activities that were highly structured or competitive [26]. Practical and interactive healthy eating sessions were highly valued such as cooking and using visual approaches, e.g., to illustrate portion size [21]. Parents and adolescents wanted interventions to be structured with meal plans and recipe ideas [24,29] and wanted healthy food that tasted good [20,24].

Overall, obesity management interventions should factor in longer term support that considers the mental health of adolescents and psychological support, as obesity management brings about feelings of failure, guilt and shame [23,29].

This finding is based on eleven reviews [19–21,23–30] (with 204 included primary qualitative studies). Concerns over the methodological limitations of the studies and richness of the data varied between the studies.

The types of diets or physical activities available should be appropriate for the child in terms of their age, gender, ethnicity, and physical capabilities.

Some children and adolescents with obesity and their parents reported that they wanted weight management programmes to be tailored or personalised [30]. The programme should be appropriate for the child/adolescent’s age, ability, culture and ethnicity [23,29]. Adolescents expressed strong feelings about the lack of services aimed at them [23]. They wanted to engage with obesity interventions that were created with their age group in mind, with strategies that matched their needs and expectations, “I like to ride a bicycle, but I can only do so for a short period of time because I feel very, very tired, and I have no strength.” [29].

Some children and adolescents with obesity reported that they found some exercises too demanding, struggling with them on account of their weight or lack of necessary skills: “I really try and sometimes give up, but most of the time I watch. It is very hard” [19,26]. The exercises left some adolescents in pain or discomfort, or too tired to do anything else [19]. As a result, some adolescents reported a history of ‘failure’, and that they felt frequently judged when in classes: “I’m not very good at a lot of things we do in PE so I get embarrassed when we do those things” [19]. These problems adversely affected children and adolescent engagement and participation. Some adolescents also reported that the required exercises or activities were too difficult to do at home [19].

Dietary management interventions should also take into account parental ability to accommodate recommendations; and give detailed plans to follow – parents noted that they wanted specific and relevant content, such as portion sizes for different ages and appropriate recipes that would be suitable for all family members [29].

This finding is based on six reviews [19,23,26,27,29,30] (with 118 included primary qualitative studies). Concerns over the methodological limitations of the studies and richness of the data varied between the studies.

Children and adolescents report that it is important not to ‘stand out’.

Some children and adolescents with obesity and their parents report that engaging in physical activities and dietary programmes can be a positive experience if the group is restricted to children and adolescents with obesity, as this offers a normalizing environment where they feel socially accepted [21,25,27]. Some parents who participated in this study felt it was good to attend and ‘speak to other parents who are trying to change things’, while their children ‘could make friends with other kids’ who could ‘play on the same level’ as their own child [25]. Conversely, standing-out in non-intervention activities was reported by some adolescents to be a highly stigmatizing experience, contributing to negative self-image, especially for girls [19,32].

This finding is based on seven reviews [19,21,23–25,27,32] (with 837 included primary qualitative studies); there were minor-to-moderate concerns regarding methodological limitations but mixed concerns regarding richness.

The quality and nature of advice on types of diet or physical activity interventions given to children and families is important (what activities might be best, how to do them, goals to aim for).

Some children and adolescents with obesity, along with their caregivers, reported that interventions should provide them with new skills and knowledge. Some preferred practical, hands-on instruction over theory: “...you don’t want to hear theory when you’re a mum. You want to hear real-life experience and what’s practical for us” [21,24,25], while others appreciated gaining evidence-based knowledge [23,25]. Some adolescents report that they liked specialist providers, who could give them structured guidance, including clear advice on goal-setting, structured meal plans, recipes, quantity and quality of foods [23,24,27,29,30]; and they wanted to know exactly what physical activities were best, “I want to start exercising, but I don’t know what exercises to do” [19,22–24]. In addition, a non-forceful approach from health workers was appreciated; and they placed value on gentle encouragement and receiving support that focused on more than just weight loss, such as self-esteem and well-being [23].

However, some children and adolescents also report that they prefer a degree of autonomy in their choice of activities, want to set their own targets during interventions [23,29], rejecting the need for maintenance of support after the intervention had ended [23].

This finding is based on nine reviews [19,21–25,27,29,30] (with 103 included primary qualitative studies); there were mixed concerns regarding methodological limitations and richness.

Cost can be a real concern for children, adolescents and their families when seeking to engage with dietary interventions or with physical activity interventions.

Concerns were expressed over costs: not just attending clinics but also accessing necessary resources [29]. Some parents reported that the need to pay for services, or a lack of insurance coverage, made it difficult to engage with the intervention [29]. Other parents were concerned at the cost of using digital tools and other resources [30]. Some parents and adolescents reported that limited finances made it difficult to eat intervention-specific foods or engage in certain exercise and physical activities [24,28].

This finding is based on five reviews [24,27–30] (with 93 included primary qualitative studies); there were mix concerns regarding methodological limitations and richness.