***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: BACKGROUND Recommending increased physical activity facilitates long-term weight loss , but the optimal level of physical activity to recommend is unknown . OBJECTIVE The objective of the study was to evaluate the efficacy for long-term weight loss of recommendations for much higher physical activity than those normally used in behavioral treatments . DESIGN Overweight men and women ( n = 202 ) were r and omly assigned to either a st and ard behavior therapy ( SBT ) for obesity , incorporating an energy expenditure ( EE ) goal of 1000 kcal/wk , or to a high physical activity ( HPA ) treatment , in which the goal was an EE of 2500 kcal/wk . To help HPA treatment group participants achieve this high exercise goal , their treatment included encouragement to recruit 1 - 3 exercise partners into the study , personal counseling from an exercise coach , and small monetary incentives . RESULTS The HPA treatment group reported achieving higher mean ( + /- SD ) physical activity levels than did the SBT group at 6 mo ( EE of 2399 + /- 1571 kcal/wk compared with 1837 + /- 1431 kcal/wk ) , 12 mo ( EE of 2249 + /- 1751 kcal/wk compared with 1565 + /- 1309 kcal/wk ) , and 18 mo ( EE of 2317 + /- 1854 kcal/wk compared with 1629 + /- 1483 kcal/wk ) ( all P < 0.01 ) . Mean ( + /- SEM ) cumulative weight losses at 6 , 12 , and 18 mo in the HPA treatment group were 9.0 + /- 7.1 , 8.5 + /- 7.9 , and 6.7 + /- 8.1 kg , respectively . In the SBT group , the corresponding weight losses were 8.1 + /- 7.4 , 6.1 + /- 8.8 , and 4.1 + /- 7.3 kg , respectively . Between-group differences in weight loss were significant at 12 and 18 mo . CONCLUSION These results suggest that recommendations of higher levels of physical activity ( EE of 2500 kcal/wk ) promote long-term weight loss better than do conventional recommendations OBJECTIVE : To investigate the sustained effectiveness of a novel skill-based intervention for weight loss . DESIGN : R and omized , controlled trial . SUBJECTS : A total of 80 overweight/obese women living in Connecticut . MEASUREMENTS : Absolute weight difference measured in pounds and absolute change in body mass index ( BMI ) . Secondary outcomes included changes in food frequency question naire ( FFQ ) data and waist-to-hip ratio . RESULTS : In all 61 , 35 , and 34 % of study participants completed the 6- , 12- , and 24-month assessment s , respectively . At 6 months postintervention , both counseling-based ( CBI ) and skill-based ( SBI ) intervention groups had statistically significant decreases in absolute weight ( 4.0±3.6 and 1.7±3.0 kg , respectively ) . Compared to their baseline values , both CBI and SBI groups still maintained weight losses at 24 months ( 1.1±5.8 and 0.59±3.3 kg , respectively ) ; however , the differences were not statistically significant . FFQ results showed that , within the SBI group , there was a significant decrease ( P<0.05 ) in percent fat from baseline to 12 months and a nearly significant decrease in saturated fat from baseline to 24 months ( P=0.07 ) . CONCLUSIONS : Both the novel SBI and conventional dietary counseling demonstrated some residual weight loss benefit at 2 y. Effects of the SBI on dietary intake patterns are encouraging , and warrant further study Purpose of review This review highlights recent work evaluating the relationship between exercise , physical activity and physical and mental health . Both cross-sectional and longitudinal studies , as well as r and omized clinical trials , are included . Special attention is given to physical conditions , including obesity , cancer , cardiovascular disease and sexual dysfunction . Furthermore , studies relating physical activity to depression and other mood states are review ed . The studies include diverse ethnic population s , including men and women , as well as several age groups ( e.g. adolescents , middle-aged and older adults ) . Recent findings Results of the studies continue to support a growing literature suggesting that exercise , physical activity and physical-activity interventions have beneficial effects across several physical and mental-health outcomes . Generally , participants engaging in regular physical activity display more desirable health outcomes across a variety of physical conditions . Similarly , participants in r and omized clinical trials of physical-activity interventions show better health outcomes , including better general and health-related quality of life , better functional capacity and better mood states . Summary The studies have several implication s for clinical practice and research . Most work suggests that exercise and physical activity are associated with better quality of life and health outcomes . Therefore , assessment and promotion of exercise and physical activity may be beneficial in achieving desired benefits across several population s. Several limitations were noted , particularly in research involving r and omized clinical trials . These trials tend to involve limited sample sizes with short follow-up periods , thus limiting the clinical implication s of the benefits associated with physical activity . Abbreviations CAD : coronary artery disease ; COPD : chronic obstructive pulmonary disease ; CRP : cardiac rehabilitation program ; CVD : cardiovascular disease ; GMCB : group-mediated cognitive – behavioural ; HRQOL : health-related quality of life Signal detection methods were used to identify predictors of successful weight loss in 177 mildly to moderately overweight women and men assigned to one of two weight-loss programs . Predictors included initial demographic , physiological , behavioral , and psychosocial characteristics , and program type ( e.g. diet-only and diet-plus-exercise ) . Successful weight loss was defined as a loss of at least two units of body mass index at one year . Four subgroups were identified . Participants in the diet-plus-exercise program who were initially more satisfied with their bodies and did not have a history of repeated weight loss were most likely to succeed ( 63 % succeeded ) . In contrast , participants assigned to the diet-plus-exercise program who were either extremely dissatisfied with their bodies or who had a history of repeated weight loss were at similar risk for failure as participants in the diet-only program ( only 26 % to 35 % succeeded ) . The results underscore the potential utility of exploring these subgroups further to inform the development of new treatment strategies to increase the likelihood of success BACKGROUND Although it is known that plasma leptin concentrations correlate with the amount of adipose tissue in the body , little information is available on the long-term effects on leptin concentrations of changes in diet and exercise . OBJECTIVE We wanted to examine whether changes in dietary energy sources and exercise-mediated energy expenditure , alone or in combination , affect plasma leptin concentrations . DESIGN In a r and omized , 2 x 2 factorial trial , 186 men with metabolic syndrome were divided into 4 groups : diet , exercise , a combination of diet and exercise , and control . Data on dietary intake , physical fitness , and demographics were collected and plasma leptin concentrations were measured before and after a 1-y intervention period . RESULTS Plasma leptin concentrations , body mass index , and fat mass decreased in association with long-term reductions in food intake as well as increased physical activity . By adjusting for either body mass index or fat mass , we observed a highly significant reduction in plasma leptin concentration after both the diet and the exercise interventions . There was no interaction between the interventions , suggesting a direct and additive effect of changes in diet and physical activity on plasma leptin concentrations . CONCLUSION Long-term changes in lifestyle consisting of decreased intake of dietary fat and increased physical activity reduced plasma leptin concentrations in humans beyond the reduction expected as a result of changes in fat mass CONTEXT The prevalence of overweight and obesity in the United States remains high . Commercial weight loss programs may contribute to efforts to reduce the prevalence of overweight and obesity , although few studies have examined their efficacy in controlled trials . OBJECTIVE To test whether a free prepared meal and incentivized structured weight loss program promotes greater weight loss and weight loss maintenance at 2 years compared with usual care . DESIGN , SETTING , AND PARTICIPANTS A r and omized controlled trial of weight loss and weight loss maintenance in 442 overweight or obese women ( body mass index , 25 - 40 ) aged 18 to 69 years ( mean age , 44 years ) conducted at US institutions over 2 years with follow-up between November 2007 and April 2010 . INTERVENTION The program , which involves in-person center-based or telephone-based one-to-one weight loss counseling , was available over a 2-year period . Behavioral goals were an energy-reduced , nutritionally adequate diet , facilitated by the inclusion of prepackaged food items in a planned menu during the initial weight loss phase , and increased physical activity . Participants assigned to usual care received 2 individualized weight loss counseling sessions with a dietetics professional and monthly contacts . MAIN OUTCOME MEASURES Weight loss and weight loss maintenance . RESULTS Weight data were available at 24 months for 407 women ( 92.1 % of the study sample ) . In an intent-to-treat analysis with baseline value substitution , mean weight loss was 7.4 kg ( 95 % confidence interval [ CI ] , 6.1 - 8.7 kg ) or 7.9 % ( 95 % CI , 6.5%-9.3 % ) of initial weight at 24 months for the center-based group , 6.2 kg ( 95 % CI , 4.9 - 7.6 kg ) or 6.8 % ( 95 % CI , 5.2%-8.4 % ) for the telephone-based group , and 2.0 kg ( 95 % CI , 0.6 - 3.3 kg ) or 2.1 % ( 95 % CI , 0.7%-3.5 % ) for the usual care control group after 24 months ( P < .001 for intervention effect ) . CONCLUSION Compared with usual care , this structured weight loss program result ed in greater weight loss over 2 years . TRIAL REGISTRATION clinical trials.gov Identifier : NCT00640900 CONTEXT Although commercial weight loss programs provide treatment to millions of clients , their efficacy has not been evaluated in rigorous long-term trials . OBJECTIVE To compare weight loss and health benefits achieved and maintained through self-help weight loss vs with a structured commercial program . DESIGN AND SETTING A 2-year , multicenter r and omized clinical trial with clinic visits at 12 , 26 , 52 , 78 , and 104 weeks conducted at 6 academic research centers in the United States between January 1998 and January 2001 . PARTICIPANTS Overweight and obese men ( n = 65 ) and women ( n = 358 ) ( body mass index , 27 - 40 ) aged 18 to 65 years . INTERVENTION R and om assignment to either a self-help program ( n = 212 ) consisting of two 20-minute counseling sessions with a nutritionist and provision of self-help re sources or to a commercial weight loss program ( n = 211 ) consisting of a food plan , an activity plan , and a cognitive restructuring behavior modification plan , delivered at weekly meetings . MAIN OUTCOME MEASURES Weight change was the primary outcome measure . Secondary outcomes included waist circumference , body mass index , blood pressure , serum lipids , glucose , and insulin levels . RESULTS At 2 years , 150 participants ( 71 % ) in the commercial group and 159 ( 75 % ) in the self-help group completed the study . In the intent-to-treat analysis , mean ( SD ) weight loss of participants in the commercial group was greater than in the self-help group at 1 year ( -4.3 [ 6.1 ] kg vs -1.3 [ 6.1 ] kg , respectively ; P<.001 ) and at 2 years ( -2.9 [ 6.5 ] kg vs -0.2 [ 6.5 ] kg , respectively ; P<.001 ) . Waist circumference ( P = .003 ) and body mass index ( P<.001 ) decreased more in the commercial group . Changes in blood pressure , lipids , glucose , and insulin levels were related to changes in weight in both groups , but between-group differences in biological parameters were mainly nonsignificant by year 2 . CONCLUSION The structured commercial weight loss program provided modest weight loss but more than self-help over a 2-year period Objectives : To describe participants ’ adherence to multiple components ( attendance , energy intake , fat gram , exercise goals , and self-monitoring eating and exercise behaviors ) of a st and ard behavioral treatment program ( SBT ) for weight loss and how adherence to these components may influence weight loss and biomarkers ( triglycerides , low density lipoproteins [ LDL ] , high density lipoprotein , and insulin ) during the intensive and less-intensive intervention phases . Methods : A secondary analysis of a r and omized clinical trial consisting of a SBT with either fat-restricted st and ard or lacto-ovo vegetarian diet . The 12-month intervention was delivered in 33 group sessions . The first six months reflected the intensive phase ; the second six months , the less-intensive intervention phase . We conducted the analysis without regard to treatment assignment . Eligible participants included overweight/obese adults ( N = 176 ; mean body mass index = 34.0 kg/m2 ) . The sample was 86.9 % female , 70.5 % White , and 44. 
    Output:
    
For percentage weight change , no significant differences were found among the BMI classes .
Conclusion Average weight change during lifestyle interventions only differs to a small extent among people with BMI between 25 and 40 kg m−2 .
This implies that these interventions are equally appropriate for these BMI classes