***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: OBJECTIVE To assess the process variables involved in a weight loss program for African-American adolescent girls . Several process variables have been identified as affecting success in in vivo weight loss programs for adults and children , including program adherence , self-efficacy , and social support . The current study sought to broaden the underst and ing of these process variables as they pertain to an intervention program that is presented using the Internet . It was hypothesized that variables such as program adherence , dietary self-efficacy , psychological factors , and family environment factors would mediate the effect of the experimental condition on weight loss . RESEARCH METHODS AND PROCEDURES Participants were 57 adolescent African-American girls who joined the program with one obese parent ; family pairs were r and omized to either a behavioral or control condition in an Internet-based weight loss program .  Outcome data ( weight loss ) are reported for the first 6 months of the intervention . RESULTS Results partially supported the hypotheses . For weight loss among adolescents , parent variables pertaining to life and family satisfaction were the strongest mediating variables . For parental weight loss , changes in dietary practice s over the course of 6 months were the strongest mediators . DISCUSSION The identification of factors that enhance or impede weight loss for adolescents is an important step in improving weight loss programs for this group . The current findings suggest that family/parental variables exert a strong influence on weight loss efforts for adolescents and should be considered in developing future programs Thirty-nine U.S. Air Force enlisted men participated in a r and omized controlled study that evaluated an experimental program design ed to enhance fitness . Subjects were assigned to either a treatment ( access to the program ) or control ( no access to program ) group for 6 months . To improve treatment group fitness ( as measured by VO2 , subjects received individually tailored information ( based on a behavior change model ) via the Internet to encourage adoption of positive diet and exercise behaviors . Results showed no significant effect in improving fitness in treatment . However , significant effects were observed for secondary outcomes such as weight ( controls , + 1.0 kg vs. treatment , -2.2 kg , p < 0.05 ) , body mass index ( + 0.3 kg/m2 vs. -0.7 kg/m2 , p < 0.05 ) , and percent body fat ( + 0.6 % vs. -1.5 % , p < 0.001 ) . The data suggest that the individually tailored exercise information was not effective in encouraging sufficient exercise intensity to impact fitness . However , the dietary tailored information appears to have encouraged the adoption of more positive nutritional practice s as demonstrated by the beneficial effects reflected in secondary outcomes Background Our aim was to compare the effects of a Paleolithic ( ' Old Stone Age ' ) diet and a diabetes diet as generally recommended on risk factors for cardiovascular disease in patients with type 2 diabetes not treated with insulin . Methods In a r and omized cross-over study , 13 patients with type 2 diabetes , 3 women and 10 men , were instructed to eat a Paleolithic diet based on lean meat , fish , fruits , vegetables , root vegetables , eggs and nuts ; and a Diabetes diet design ed in accordance with dietary guidelines during two consecutive 3-month periods . Outcome variables included changes in weight , waist circumference , serum lipids , C-reactive protein , blood pressure , glycated haemoglobin ( HbA1c ) , and areas under the curve for plasma glucose and plasma insulin  in the 75 g oral glucose tolerance test . Dietary intake was evaluated by use of 4-day weighed food records . Results Study participants had on average a diabetes duration of 9 years , a mean HbA1c of 6,6 % units by Mono-S st and ard and were usually treated with metformin alone ( 3 subjects ) or metformin in combination with a sulfonylurea ( 3 subjects ) or a thiazolidinedione ( 3 subjects ) . Mean average dose of metformin was 1031 mg per day . Compared to the diabetes diet , the Paleolithic diet result ed in lower mean values of HbA1c ( -0.4 % units , p = 0.01 ) , triacylglycerol ( -0.4 mmol/L , p = 0.003 ) , diastolic blood pressure ( -4 mmHg , p = 0.03 ) , weight ( -3 kg , p = 0.01 ) , BMI ( -1 kg/m2 , p = 0.04 ) and waist circumference ( -4 cm , p = 0.02 ) , and higher mean values of high density lipoprotein cholesterol ( + 0.08 mmol/L , p = 0.03 ) . The Paleolithic diet was mainly lower in cereals and dairy products , and higher in fruits , vegetables , meat and eggs , as compared with the Diabetes diet . Further , the Paleolithic diet was lower in total energy , energy density , carbohydrate , dietary glycemic load , saturated fatty acids and calcium , and higher in unsaturated fatty acids , dietary cholesterol and several vitamins . Dietary GI was slightly lower in the Paleolithic diet ( GI = 50 ) than in the Diabetic diet ( GI = 55 ) . Conclusion Over a 3-month study period , a Paleolithic diet improved glycemic control and several cardiovascular risk factors compared to a Diabetes diet in patients with type 2 diabetes . Trial registration Clinical Trials.gov NCT00435240 OBJECTIVES To identify diabetes-related characteristics of individuals at different stages of readiness to change to healthy ,  low-fat eating . RESEARCH DESIGN AND METHODS Stage-based differences in demographic , eating-related , health care utilization , and psychosocial factors were examined in a sample of 768 overweight ( BMI > 27 kg/m(2 ) ) individuals with diabetes enrolled in a r and omized behavioral intervention trial . RESULTS Stage-based differences occurred for type 1 diabetic participants on percent of calories from fat and number of daily vegetable servings . For type 2 diabetic participants , sex , disease-specific quality of life , percent calories from fat , and number of daily vegetables servings differed across stages . Those in action stages were more likely to be female and have a better quality of life and healthier eating habits .  Type 2 diabetic insulin-requiring participants in action stages were more likely to be married . Social support was highest for those in the contemplation stage and lowest for those in the action stage . Type 2 diabetic participants on pills in the action stages were older , had a lower BMI , ate more fruit , were nonsmokers , recently attended diabetes education , had a better quality of life and social support , and had less stress . One anomalous finding for type 2 diabetic participants was that precontemplators scored similarly to those in action stages . CONCLUSIONS These data vali date the Transtheoretical Model , where those in the action stages displayed healthier eating . They also indicate that demographic and psychosocial factors may mediate readiness to change diet . Precontemplators were a heterogeneous group and may need individually tailored interventions Data from two r and omized clinical trials ( RCT ) were used to examine the extent to which a health promotion intervention affected changes in growth trajectories of psychosocial constructs and if so , whether these constructs in turn explained changes in  physical activity ( PA ) . PA and psychosocial measures on 842 overweight adults in the United States were collected in two RCTs evaluating Internet-based behavior change interventions with assessment s at baseline , 6 and 12 months . A physical activity latent variable at 12 months was created using indicators of self-reported walking and leisure time activities . Intervention-mediated effects on  PA  at 12 months were found via latent growth curves representing self-efficacy and behavioral strategies , where increasing growth curves across time were associated with higher  PA values at 12 months . These findings provide some evidence that web-based self-help intervention programs worked through targeted behavior change constructs to influence physical activity levels in overweight adults Background Successfully transferring the findings of expensive and tightly controlled programmes of intensive lifestyle modification to the primary care setting is necessary if such knowledge is to be of clinical utility . The objective of this study was to test whether intensive lifestyle modification , shown previously in tightly-controlled clinical trials to be efficacious for diabetes risk-reduction among high-risk individuals , can reduce cardiovascular risk factor levels in the primary care setting . Methodology / Principal Findings The Swedish Björknäs study was a r and omized controlled trial conducted from 2003 to 2006 with follow-up on cardiovascular risk factors at 3 , 12 , 24 and 36 months . A total of 151 middle-aged men and women at moderate- to high-risk of cardiovascular disease from northern Sweden were r and omly assigned to either an intensive lifestyle intervention ( n = 75 ) or control ( n = 76 ) group . The intervention was based broadly on the protocol of the Diabetes Prevention Program . The three-month intervention period was administered in the primary care setting and consisted of supervised exercise sessions and diet counselling , followed by regular group meetings during three years . The control group was given general advice about diet and exercise and received st and ard clinical care . Outcomes were changes in anthropometrics , aerobic fitness , self-reported physical activity , blood pressure , and metabolic traits . At 36 months post-r and omisation , intensive lifestyle modification  reduced waist circumference ( −2.2 cm : p = 0.001 ) , waist-hip ratio ( −0.02 : p<0.0001 ) , systolic blood pressure ( −4.9 mmHg : p = 0.036 ) , and diastolic blood pressure ( −1.6 mmHg : p = 0.005 ) , and improved aerobic fitness ( 5 % ; p = 0.038 ) . Changes in lipid or glucose values did not differ statistically between groups . At 36 months , self-reported time spent exercising and total physical activity had increased more in the intervention group than in the control group ( p<0.001 ) . Conclusion / Significance A program of intensive lifestyle modification undertaken in the primary health care setting can favourably influence cardiovascular risk-factor profiles in high-risk individuals . Trial Registration Clinical Trials.gov Background Research on the motivational model proposed by Self-Determination Theory ( SDT ) provides theoretically sound insights into reasons why people adopt and maintain exercise and other health behaviors , and allows for a meaningful analysis of the motivational processes involved in behavioral self-regulation . Although obesity is notoriously difficult to reverse and its recidivism is high , adopting and maintaining a physically active lifestyle is arguably the most effective strategy to counteract it in the long-term . The purpose s of this study are twofold : i ) to describe a 3-year r and omized controlled trial ( RCT ) aim ed at testing a novel obesity treatment program based on SDT , and ii ) to present the rationale behind SDT 's utility in facilitating and explaining health behavior change , especially physical activity/exercise , during obesity treatment . Methods Study design , recruitment , inclusion criteria , measurements , and a detailed description of the intervention ( general format , goals for the participants , intervention curriculum , and main SDT strategies ) are presented . The intervention consists of a 1-year group behavioral program  for overweight and moderately obese women , aged 25 to 50 ( and pre-menopausal ) , recruited from the community at large through media advertisement . Participants in the intervention group meet weekly or bi-weekly with a multidisciplinary intervention team ( 30 2 h sessions in total ) , and go through a program covering most topics considered critical for successful  weight control .  These topics and especially their delivery were adapted to comply with SDT and Motivational Interviewing guidelines . Comparison group receive a general health education curriculum . After the program , all subjects are follow-up for a period of 2 years . Discussion Results from this RCT will contribute to a better underst and ing of how motivational characteristics , particularly those related to physical activity/exercise behavioral self-regulation , influence treatment success , while exploring the utility of Self-Determination Theory for promoting health behavior change in the context of obesity . Trial Registration Clinical Trials Gov. Identifier Research on the conceptualization of adherence to treatment has not addressed a key question : Is adherence best defined as being a uni-dimensional or multi-dimensional behavioral construct ? The primary aim of this study was to test which of these conceptual models best described adherence to a weight management program . This ancillary study was conducted as a part of the POUNDS LOST trial that tested the efficacy of four dietary macronutrient compositions for promoting weight loss .  A sample of 811 overweight/obese adults was recruited across two clinical sites , and each participant was r and omly assigned to one of four macronutrient prescriptions : ( 1 ) Low fat ( 20 % of energy ) , average protein ( 15 % of energy ) ; ( 2 ) High fat ( 40 % ) , average protein ( 15 % ) ; ( 3 ) Low fat ( 20 % ) , high protein ( 25 % ) ; ( 4 ) High fat ( 40 % ) , high protein ( 25 % ) . Throughout the first 6 months of the study , a computer tracking system collected data on eight indicators of adherence . Computer tracking data from the initial 6 months of the intervention were analyzed using exploratory and confirmatory analyses . Two factors ( accounting for 66 % of the variance ) were identified and confirmed : ( 1 ) behavioral adherence and ( 2 ) dietary adherence . Behavioral adherence did not differ across the four interventions , but prescription of a high fat diet ( vs. a low fat di 
    Output:
    
The intervention was found to have limited impact on weight loss ( about 2 kg or less ) and other outcome measures .
There was no conclusive evidence for sustainable weight loss .
However , TTM SOC and a combination of physical activity , diet and other interventions tended to produce significant outcomes ( particularly change in physical activity and dietary intake ) .
TTM SOC and a combination of physical activity , diet and other interventions result ed in minimal weight loss , and there was no conclusive evidence for sustainable weight loss .