***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 This study examined whether the combination of alternate day fasting ( ADF ) plus exercise produces superior changes in body composition and plasma lipid levels when compared to each intervention alone . DESIGN AND METHODS Obese subjects ( n = 64 ) were r and omized to 1 of 4 groups for 12 weeks : 1 ) combination ( ADF plus endurance exercise ) , 2 ) ADF , 3 ) exercise , or 4 ) control .  RESULTS Body weight was reduced ( P < 0.05 ) by 6 ± 4 kg , 3 ± 1 kg , and 1 ± 0 kg in the combination , ADF , and exercise groups , respectively . Fat mass and waist circumference decreased ( P < 0.001 ) , while lean mass was retained in the combination group . Low-density lipoprotein ( LDL ) cholesterol decreased ( 12 ± 5 % , P < 0.05 ) and high-density lipoprotein ( HDL ) cholesterol increased ( 18 ± 9 % , P < 0.05 ) in the combination group only . LDL particle size increased ( P < 0.001 ) by 4 ± 1 Å and 5 ± 1 Å in the combination and ADF groups , respectively . The proportion of small HDL particles decreased ( P < 0.01 ) in the combination group only . CONCLUSIONS These findings suggest that the combination produces superior changes in body weight , body composition , and lipid indicators of heart disease risk , when compared to individual treatments BACKGROUND Weight loss due to a negative energy balance is considered to be accompanied by a decrease in physical activity . OBJECTIVE The aim of this study was to investigate whether a decrease in physical activity is sustained during weight maintenance . DESIGN Subjects were 20 men and 31 women [ mean ( ±SD ) age : 42 ± 8 y ; BMI ( in kg/m(2 ) ) : 31.4 ± 2.8 ] . Weight loss was achieved by an 8-wk very-low-energy diet period , followed by 44 wk of weight maintenance . Physical activity measures were total energy expenditure expressed as a multiple of sleeping metabolic rate ( PALSMR ) and resting metabolic rate ( PALRMR ) , activity-induced energy expenditure divided by body weight ( AEE/kg ) , and activity counts measured by a triaxial accelerometer . Measurements took place at 0 , 8 , and 52 wk . RESULTS Body mass decreased significantly during the diet period ( 10.5 ± 3.8 % , P < 0.001 ) , and this reduction was sustained after 52 wk ( 6.0 ± 5.1 % , P < 0.001 ) . PALSMR and PALRMR decreased from 1.81 ± 0.23 and 1.70 ± 0.22 , respectively , before the diet to 1.69 ± 0.20 and 1.55 ± 0.19 after the diet ( P < 0.001 ) and increased again after weight maintenance to 1.85 ± 0.27 and 1.71 ± 0.23 , respectively , compared with 8-wk measurements ( P < 0.001 ) . AEE/kg decreased from 0.043 ± 0.015 MJ/kg at baseline to 0.037 ± 0.014 MJ/kg after the diet ( P < 0.001 ) and was higher after 52 wk ( 0.044 ± 0.17 MJ/kg ) compared with after 8 wk ( P < 0.001 ) . Activity counts decreased from 1.64 ± 0.37 megacounts/d at baseline to 1.54 ± 0.35 megacounts/d after the diet ( P < 0.05 ) and were higher after 52 wk ( 1.73 ± 0.49 megacounts/d ) compared with 8 wk ( P < 0.01 ) . CONCLUSION A weight loss-induced reduction in physical activity returns to baseline values when weight loss is maintained . This trial was registered at clinical trials.gov as NCT01015508 Introduction Changes in sex hormones with weight loss might have implication s for breast cancer prevention but have not been examined extensively , particularly in African-American ( AA ) women . Methods We conducted a prospect i ve study of 278 overweight/obese postmenopausal women ( 38 % AA ) not taking hormone therapy within the Weight Loss Maintenance Trial . All participants lost at least 4 kg after a 6-month weight-loss phase and attempted to maintain weight loss during the subsequent 12 months . We evaluated the percentage changes in estrone , estradiol , free estradiol , testosterone , free testosterone , and rostenedione , dehydroepi and rosterone sulfate and sex hormone-binding globulin ( SHBG ) using generalized estimating equations . Results In all study phases , AA women had higher levels of estrogen and testosterone concentrations , independent of adiposity . On average , participants lost 7.7 kg during the weight-loss phase , and concentrations of estrone ( -5.7 % , P = 0.006 ) , estradiol ( -9.9 % , P < 0.001 ) , free estradiol ( -13.4 % , P < 0.0001 ) , and free testosterone ( -9.9 % , P < 0.0001 ) decreased , while the SHBG concentration ( 16.2 % , P < 0.001 ) increased . Weight change did not significantly affect total testosterone or other and rogen concentrations . Compared with non-AA women , AA women experienced less change in estrogens per kilogram of weight change ( that is , per 1 kg weight loss : estrone , -0.6 % vs. -1.2 % , P-interaction = 0.10 ; estradiol , -1.1 % vs. -1.9 % , P-interaction = 0.04 ; SHBG , 0.9 % vs. 1.6 % , P-interaction = 0.006 ; free estradiol , -1.4 % vs. -2.1 % , P-interaction = 0.01 ) . Conclusion To the best of our knowledge this is the first study to examine and compare the effects of intentional weight loss and maintenance on a panel of sex hormones in AA women and non-AA women . Although speculative , these data suggest hormonal differences may contribute to different racial patterns of breast cancer incidence and mortality and encourage further investigations to underst and the long-term effects of weight loss on sex hormones in obese postmenopausal women . Trial Registration Clinical Trials.gov : Background : Alternate day fasting ( ADF ) with a low-fat ( LF ) diet improves brachial artery flow-mediated dilation ( FMD ) . Whether these beneficial effects can be reproduced with a high-fat ( HF ) diet remains unclear . Objective : This study compared the effects of ADF-HF to ADF-LF regimens on FMD . The role that adipokines have in mediating this effect was also investigated . Methods : Thirty-two obese subjects were r and omized to an ADF-HF  ( 45 % fat )  or ADF-LF diet ( 25 % fat ) , consisting of two phases : ( 1 ) a 2-week baseline weight maintenance period and ( 2 ) an 8-week ADF weight loss period . Food was provided throughout the study . Results : Body weight was reduced ( P<0.0001 ) in the ADF-HF ( 4.4±1.0 kg ) and ADF-LF group ( 3.7±0.7 kg ) . FMD decreased ( P<0.05 ) by ADF-HF relative to baseline ( 7±1 to 5±2 % ) and increased ( P<0.05 ) by ADF-LF ( 5±1 to 7±2 % ) . Blood pressure remained unchanged in both groups . Adiponectin increased ( P<0.05 ) in the ADF-HF ( 43±7 % ) and ADF-LF group ( 51±7 % ) . Leptin and resistin decreased ( P<0.05 ) in the ADF-HF ( 32±5 % ; 23±5 % ) and ADF-LF group ( 30±3 % ; 27±4 % ) . Increases in adiponectin were associated with augmented FMD in the ADF-LF group only ( r=0.34 , P=0.03 ) . Conclusion : Thus , improvements in FMD  with ADF may only occur with LF diets and not with HF diets , and adipokines may not have a significant role in mediating this effect BACKGROUND : A relatively high percentage of energy intake as protein has been shown to increase satiety and decrease energy efficiency during overfeeding . AIM : To investigate whether addition of protein may improve weight maintenance by preventing or limiting weight regain after weight loss of 5–10 % in moderately obese subjects . DESIGN OF THE STUDY : In a r and omized parallel design , 148 male and female subjects ( age 44.2±10.1 y ; body mass index ( BMI ) 29.5±2.5 kg/m2 ; body fat 37.2±5.0 % ) followed a very low-energy diet ( 2.1 MJ/day ) during 4 weeks . For subsequent 3 months weight-maintenance assessment , they were stratified according to age , BMI , body weight , restrained eating , and resting energy expenditure ( REE ) , and r and omized over two groups . Both groups visited the University with the same frequency , receiving the same counseling on dem and by the dietitian . One group ( n=73 ) received 48.2 g/day additional protein to their diet . Measurements at baseline , after weight loss , and after 3 months weight maintenance were body weight , body composition , metabolic measurements , appetite profile , eating attitude , and relevant blood parameters . RESULTS : Changes in body mass , waist circumference , REE , respiratory quotient ( RQ ) , total energy expenditure ( TEE ) , dietary restraint , fasting blood-glucose , insulin , triacylglycerol , leptin , β-hydroxybutyrate , glycerol , and free fatty acids were significant during weight loss and did not differ between groups . During weight maintenance , the ‘ additional-protein group ’ showed in comparison to the nonadditional-protein group 18 vs 15 en% protein intake , a 50 % lower body weight regain only consisting of fat-free mass , a 50 % decreased energy efficiency , increased satiety while energy intake did not differ , and a lower increase in triacylglycerol and in leptin ; REE , RQ , TEE , and increases in other blood parameters measured did not differ . CONCLUSION : A 20 % higher protein intake , that is , 18 % of energy vs 15 % of energy during weight maintenance after weight loss , result ed in a 50 % lower body weight regain , only consisting of fat-free mass , and related to increased satiety and decreased energy efficiency Thirty obese women were r and omly assigned to either 40 % [ severe energy restriction ( SER ) ] or 70 % [ moderate energy restriction ( MER ) ] of their maintenance energy requirements and to no exercise , aerobic exercise ( walking ) , or aerobic exercise plus circuit weight training .  Body composition by hydrostatic weighing and energy expenditure by indirect calorimetry were measured at 0 , 3 , and 6 mo . In addition , we developed a deficit-efficiency factor ( DEF ) , calculated as body energy loss/dietary energy deficit , to attempt to quantify the effectiveness of the weight-reduction interventions . Subjects in the SER group lost more weight ( mean + /- SE : 15.1 + /- 1.4 vs 10.8 + /- 1.0 kg ) , fat ( 11.7 + /- 1.1 vs 8.3 + /- 0.6 kg ) , and fat-free mass ( 2.8 + /- 0.3 vs 1.8 + /- 0.3 kg ) than the MER group ( P < or = 0.05 ) . However , the overall DEF was greatest in the MER group ( 0.80 + /- 0.07 ) compared with the SER group ( 0.52 + /- 0.05 ; P < or = 0.01 ) . Exercise had no significant effect . This study demonstrates that MER may offer an advantage over SER because it produces a greater energy loss relative to energy deficit This study examined the effects of calorie alternation and exercise on weight loss .  Moderately obese women ( 130 - 160 % of ideal body weight ) were r and omly assigned to an alternating- or constant-calorie diet with or without aerobic exercise . Both diets provided an average of 1200 kcal/d over a 12-wk period ; daily intake of subjects in the alternating-diet condition varied in a prescribed pattern from 600 to 1800 kcal/d . Exercising subjects walked 5 d/wk . All subjects participated in an intensive outpatient behavior-modification program . At the end of the study , exercised subjects had greater reductions in body weight and body fat percentage than did nonexercised subjects . The type of caloric restriction did not affect weight or fat loss . Changes in resting metabolic rate did not differ among groups . Alternating calories was neither beneficial nor detrimental as a weight-loss strategy whereas exercise was clearly beneficial in weight-loss therapy Weight loss reduces energy expenditure , but it is unclear whether dietary macronutrient composition affects this reduction . We hypothesized that energy expenditure might be modulated by macronutrient composition of the diet . The PO 
    Output:
    
Intermittent fasting thus represents a valid -- albeit apparently not superior -- option to continuous energy restriction for weight loss