***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVES To investigate the previous dieting experiences and expectations of individuals enrolled in a r and omized trial of four commercial weight loss programmes  and post-intervention to compare experiences across the diet groups . AIM The purpose of this study was to enhance the underst and ing of why subjects volunteered to take part in a weight loss trial and also to ascertain their views on each of the diets tested . METHODS Focus groups containing both men and women were undertaken at baseline prior to r and omization , and diet specific focus groups were held post-intervention . All group discussion s were recorded and transcribed verbatim and analysed for emerging themes using the long-table approach . RESULTS The main intrinsic motivators to enroling in the study were a current lack of self-esteem and confidence . The opportunity to take part in an academic study was also a motivator . Motivation and increasing efficacy were cited commonly among those who had successfully lost ( or at least not gained ) weight . The ' pros ' identified for each of the commercial diets tested in the trial were in line with each of the diet 's promotional material s ; the ' cons ' varied between groups . CONCLUSION In this study , reducing health risks was not the main motivator for people deciding to lose weight . Increasing intrinsic sense of worth gained by losing weight and continued motivation appear to be related to success . The differing experiences of people undertaking each of the four diets suggest that matching diet regimen to individual is important Background The prevalence of obesity in men is rising , but they are less likely than women to engage in existing weight management programmes . The potential of professional sports club setting s to engage men in health promotion activities is being increasingly recognised . This paper describes the development and optimization of the  Football Fans in Training ( FFIT ) programme , which aims to help overweight men ( many of them football supporters ) lose weight through becoming more active and adopting healthier eating habits . Methods The MRC Framework for the design and evaluation of complex interventions was used to guide programme development in two phases . In Phase 1 , a multidisciplinary working group developed the pilot programme ( p-FFIT ) and used a scoping review to summarize previous research and identify the target population . Phase 2 involved a process evaluation of p-FFIT  in 11 Scottish Premier League ( SPL ) clubs . Participant and coach feedback , focus group discussion s and interviews explored the utility/acceptability of programme components and suggestions for changes . Programme session observations identified examples of good practice and problems/issues with delivery . Together , these findings informed redevelopment of the optimized programme ( FFIT ) , whose components were mapped onto specific behaviour change techniques using an evidence -based taxonomy . Results p-FFIT comprised 12 , weekly , gender-sensitised , group-based weight management classroom and ‘ pitch-side ’ physical activity sessions . These in-stadia sessions were complemented by an incremental , pedometer-based walking programme . p-FFIT was targeted at men aged 35 - 65 years with body mass index ≥ 27 kg/m2 . Phase 2 demonstrated that participants in p-FFIT were enthusiastic about both the classroom and physical activity components , and valued the camaraderie and peer-support offered by the programme . Coaches appreciated the simplicity of the key healthy eating and physical activity messages . Suggestions for improvements that were incorporated into the optimized FFIT programme included : more varied in-stadia physical activity with football-related components ; post-programme weight management support ( emails and a reunion session ) ; and additional training for coaches in SMART goal setting and the pedometer-based walking programme . Conclusions The Football Fans in Training programme is highly acceptable to participants and SPL coaches , and is appropriate for evaluation in a r and omised controlled trial Background The prevalence of male obesity is increasing , but men are less likely than women to attend existing weight management programmes . We have taken a novel approach to reducing perceived barriers to weight loss for men by using professional football ( soccer ) clubs to encourage participation in a weight management group programme , gender-sensitised in content and style of delivery .  Football Fans in Training ( FFIT ) provides 12 weeks of weight loss , physical activity and healthy eating advice at top professional football clubs in Scotl and . This pilot r and omized trial explored the feasibility of using these clubs as a setting for a r and omized controlled trial of 12 month weight loss following men ’s participation in FFIT . Methods A two-arm pilot trial at two Scottish Premier League football clubs ( one large , one smaller ) , with 103 men ( aged 35–65 , body mass index ( BMI ) ≥27 kg/m2 ) individually r and omized to  the intervention ( n=51 , received the pilot programme ( p-FFIT ) immediately ) and waitlist comparison ( n=52 , received p-FFIT after four months ) groups . Feasibility of recruitment , r and omization , data collection and retention were assessed . Objective physical measurements ( weight , waist circumference , blood pressure , body composition ) and question naires ( self-reported physical activity , diet , alcohol consumption , psychological outcomes ) were obtained from both groups by fieldworkers trained to st and ard protocol s at baseline and 12 weeks , and from the intervention group at 6 and 12 months . Qualitative methods elicited men ’s experiences of participation in the pilot trial . Results Following a short recruitment period , the recruitment target was achieved at the large , but not smaller , club . Participants ’ mean age was 47.1±8.4 years ; mean BMI 34.5±5.0 kg/m2 . Retention through the trial was good ( > 80 % at 12 weeks and 6 months ; > 75 % at 12 months ) , and 76 % attended at least 80 % of available programme delivery sessions . At 12 weeks , the intervention group lost significantly more weight than the comparison group ( 4.6 % c.f . -0.6 % , p<.001 ) and many maintained this to 12 months ( intervention group baseline-12 month weight loss : 3.5 % , p<.001 ) . There were also improvements in self-reported physical activity and diet , many sustained long term . Conclusions The results demonstrated the feasibility of trial procedures and the potential of FFIT to engage men in sustained weight loss and positive lifestyle change . They supported the conduct of a fully-powered r and omized controlled trial Background The prevalence of obesity in men in the UK is amongst the highest in Europe but men are less likely than women to use existing weight loss programmes . Developing weight management programmes which are appealing and acceptable to men is a public health priority . Football Fans in Training ( FFIT ) , a men-only weight management programme delivered to groups of men at top professional football clubs , encourages men to lose weight by working with , not against , cultural ideals of masculinity . To inform further development of interventions in football club setting s , the current study explored who is attracted to FFIT and why overweight/obese men choose to take part . Methods A mixed- methods study analysing baseline data on 747 men aged 35–65 years with BMI ≥ 28 kg/m2 who were participants in a r and omised controlled trial of FFIT , and data from 13 focus group discussion s with 63 men who had attended the programme . Results Objective ly-measured mean body mass index was 35.3 kg/m2 ( sd 4.9 ) . Overall over 90 % of participants were at very high or extremely high risk of future ill-health . Around three-quarters of participants in all age groups were at ‘ very high ’ risk of type 2 diabetes , hypertension and cardiovascular disease ( 72 % , 73 % and 80 % of men aged 35–44 , 45–54 and 55–64 years respectively ) . A further 21 % , 16 % and 13 % were at ‘ extremely high ’ risk . Qualitative data revealed that the powerful ‘ draw ’ of the football club attracted men otherwise reluctant to attend existing weight management programmes . The location and style of delivery of early FFIT sessions fostered team spirit ; men appreciated being with others ‘ like them ’ and the opportunity to undertake weight management in circumstances that enhanced physical and symbolic proximity to something they valued highly , the football club . Conclusions The delivery of a weight management intervention via professional football clubs attracted men at high risk of ill-health . The setting enabled men to join a weight management programme in circumstances that felt ‘ right ’ rather than threatening to themselves as men . FFIT is an example of how to facilitate health promotion activities in a way that is consistent with , rather than challenging to , common ideals of masculinity Background Process evaluation is important for improving theories of behavior change and behavioral intervention methods . The present study reports on the process outcomes of a pilot test of the theoretical model ( the Process Model for Lifestyle Behavior Change ; PMLBC ) underpinning an evidence -informed , theory-driven , group-based intervention design ed to promote healthy eating and physical activity for people with high cardiovascular risk . Methods 108 people at high risk of diabetes or heart disease were r and omized to a group-based weight management intervention targeting diet and physical activity plus usual care , or to usual care . The intervention comprised nine group based sessions design ed to promote motivation , social support , self-regulation and underst and ing of the behavior change process . Weight loss , diet , physical activity and theoretically defined mediators of change were measured pre-intervention , and after four and 12 months . Results The intervention result ed in significant improvements in fiber intake ( M between-group difference = 5.7 g/day , p < .001 ) but not fat consumption ( −2.3 g/day , p = 0.13 ) , that were predictive of weight loss at both four months ( M between-group difference = −1.98 kg , p < .01 ; R2 = 0.2 , p < 0.005 ) , and 12 months ( M difference = −1.85 kg , p = 0.1 ; R2 = 0.1 , p < 0.01 ) . The intervention was successful in improving the majority of specified mediators of behavior change , and the predicted mechanisms of change specified in the PMBLC were largely supported . Improvements in self-efficacy and underst and ing of the behavior change process were associated with engagement in coping planning and self-monitoring activities , and successful dietary change at four and 12 months . While participants reported improvements in motivational and social support variables , there was no effect of these , or of the intervention overall , on physical activity . Conclusions The data broadly support the theoretical model for supporting some dietary changes , but not for physical activity . Systematic intervention design allowed us to identify where improvements to the intervention may be implemented to promote change in all proposed mediators . More work is needed to explore effective mechanisms within interventions to promote physical activity behavior Objective To explore the reasons for enrolling , experiences of participating and reasons for remaining in a family-based , cluster r and omised controlled trial of a dietitian-delivered lifestyle modification intervention aim ing to reduce obesity in South Asians at high risk of developing diabetes . Design Qualitative study using narrative interviews of a purposive sample of trial participants following completion of the intervention . Data were thematically analysed . Setting The intervention was conducted in Scotl and and result ed in a modest decrease in weight , but did not statistically reduce the incidence of diabetes . Participants We conducted 21 narrative interviews with 24 participants ( 20 trial participants and four family volunteers ) . Results Many participants were motivated to participate because of : known family history of diabetes and the desire to better underst and diabetes-related risks to their own and their family 's health ; ways to mitigate these risks and to benefit from personalised monitoring . Home-based interventions , communication in the participant 's chosen language ( s ) and continuity in dietitians supported their continuing engagement with the trial . Adaptations in food choices were initially accommo date d by participants , although social and faith-based responsibilities were reported as important barriers to persevering with agreed dietary goals . Many participants reported that increasing their level of physical activity was difficult given their long working hours , physically dem and ing employment and domestic commitments ; this being compounded by Scotl and 's challenging climate and a related reluctance to exercise in the outdoors . Conclusions Although participants had strong personal interests in participation and found the information provided by dietitians useful , they nonetheless struggled to incorporate the dietary and exercise recommendations into their daily lives . In particular , increasing levels of physical exercise was described as an additional and in some cases unachievable burden . Consideration needs to be given to strengthening and supporting lifestyle interventions with community-based approaches in order to help overcome wider social and environmental factors R and omized trials of complex public health interventions generally aim to identify what works , accrediting specific intervention ' products ' as effective . This approach often fails to give sufficient consideration to how intervention components interact with each other and with local context . ' Realists ' argue that trials misunderst and the scientific method , offer only a ' successionist ' approach to causation , which brackets out the complexity of social causation , and fail to ask which interventions work , for whom and under what circumstances . We counter-argue that trials are useful in evaluating social interventions because r and omized control groups actually take proper account of rather than bracket out the complexity of social causation . Nonetheless , realists are right to stress underst and ing of ' what works , for whom and under what circumstances ' and to argue for the importance of theorizing and empirically examining underlying mechanisms . We propose that these aims can be ( and sometimes already are ) examined within r and omized trials . Such ' realist ' trials should aim to : examine the effects of intervention components separately and in combination , for example using multi-arm studies and factorial trials ; explore mechanisms of change , for example analysing how pathway variables mediate intervention effects ; use multiple trials across context s to test how intervention effects vary with context ; draw on complementary qualitative and quantitative data ; and be oriented towards building and validating ' mid-level ' program theories which would set out how interventions interact with context to produce outcomes . This last suggestion resonates with recent suggestions that , in delivering truly ' complex ' interventions , fidelity is important not so much in terms of precise activities but , rather , key intervention ' processes ' and ' functions ' . Realist trials would additionally determine the validity of program theory rather than only examining ' what works ' to better inform policy and practice in the long-term PURPOSE We explored participants ’ accounts of weight loss inter 
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MAIN RESULTS Service users were emphatic that supportive relationships , with service providers or WMP peers , are the most critical aspect of WMPs .
Supportive relationships were described as providing an extrinsic motivator or " hook " which helped to overcome barriers such as scepticism about dietary advice or a lack confidence to engage in physical activity .
DISCUSSION AND CONCLUSIONS The evidence revealed that service-users ' underst and ings of the critical features of WMPs differ from the focus of health promotion guidance or descriptions of evaluated programmes which largely emphasize educational or goal setting aspects of WMPs .
Existing programme guidance may not therefore fully address the needs of service users .
The study illustrates that the perspectives of service users can reveal unanticipated intervention mechanisms or underemphasized critical features and underscores the value of a holistic underst and ing about " what happens " in complex psychosocial interventions such as WMPs