***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: We examined the interaction of two different frequencies of aerobic exercise training ( 30 min at 50 - 60 % of maximal heart rate reserve per session ) and a self-administered caloric restriction program on the changes in subcutaneous ( SFM ) and visceral ( VFM ) fat mass over a period of 13 wk . Twenty-six sedentary young women ( 27.9 % body fat ) were r and omized into three groups : nonexercising control ( C , N = 8) ; 1 - 2 sessions/wk plus a 240 kcal caloric restriction ( 1 - 2SW , N = 9 ) ; and 3 - 4 sessions/wk without caloric restriction ( 3 - 4SW , N = 9 ) . There was a equivalent decrease in the percentage of body fat and total fat mass in both exercise groups compared with that in C. Reduction in SFM was significant in 3 - 4SW , but not in 1 - 2SW or C. A negative correlation was observed between training frequency and changes in SFM ( r = -0.65 ) . In contrast , VFM decreased significantly and equivalently in both 1 - 2SW and 3 - 4SW , but there was no correlation between training frequency and changes in VFM ( r = 0.20 ) . It is suggested that the decrease in SFM , but not VFM , is proportional to the amount of aerobic exercise training . A change in VFM appears to be related to an deficit in caloric balance either by dietary restriction ( decrease caloric intake ) or by increased caloric expenditure Background It has been suggested that exercise training results in compensatory mechanisms that attenuate weight loss . However , this has only been examined with large doses of exercise . The goal of this analysis was to examine actual weight loss compared to predicted weight loss ( compensation ) across different doses of exercise in a controlled trial of sedentary , overweight or obese postmenopausal women ( n = 411 ) . Methodology /Principal Findings Participants were r and omized to a non-exercise control ( n = 94 ) or 1 of 3 exercise groups ; exercise energy expenditure of 4 ( n = 139 ) , 8 ( n = 85 ) , or 12 ( n = 93 ) kcal/kg/week ( KKW ) . Training intensity was set at the heart rate associated with 50 % of each woman 's peak VO2 and the intervention period was 6 months . All exercise was supervised . The main outcomes were actual weight loss , predicted weight loss ( exercise energy expenditure/ 7700 kcal per kg ) , compensation ( actual minus predicted weight loss ) and waist circumference .  The study sample had a mean ( SD ) age 57.2 ( 6.3 ) years , BMI of 31.7 ( 3.8 ) kg/m2 , and was 63.5 % Caucasian . The adherence to the intervention was > 99 % in all exercise groups . The mean ( 95 % CI ) weight loss in the 4 , 8 and 12 KKW groups was −1.4 ( −2.0 , −0.8 ) , −2.1 ( −2.9 , −1.4 ) and −1.5 ( −2.2 , −0.8 ) kg , respectively . In the 4 and 8 KKW groups the actual weight loss closely matched the predicted weight loss of −1.0 and −2.0 kg , respectively , result ing in no significant compensation . In the 12 KKW group the actual weight loss was less than the predicted weight loss ( −2.7 kg ) result ing in 1.2 ( 0.5 , 1.9 ) kg of compensation ( P<0.05 compared to 4 and 8 KKW groups ) . All exercise groups had a significant reduction in waist circumference which was independent of changes in weight . Conclusion In this study of previously sedentary , overweight or obese , postmenopausal women we observed no difference in the actual and predicted weight loss with 4 and 8 KKW of exercise ( 72 and 136 minutes respectively ) , while the 12 KKW ( 194 minutes ) produced only about half of the predicted weight loss . However , all exercise groups had a significant reduction in waist circumference which was independent of changes in weight . Trial Registration Clinical Trials.gov NCT OBJECTIVE : To determine the time course for changes in aerobic capacity , body weight ( BW ) , and composition in overweight adults in response to a supervised exercise trial with a targeted energy expenditure of 2000 kcal week−1 . DESIGN : The Midwest Exercise Trial ( MET ) was a r and omized , controlled , 16-month verified , supervised exercise trial . Aerobic exercise progressed to 45 min day−1 , 5 days week−1 over 6-months and was then maintained for 10 months . Controls maintained their normal physical activity and all participants maintained ad libitum diets . SUBJECTS : A total of 131 participants were r and omized to exercise or control groups and 74 completed the intervention and all laboratory testing . MEASUREMENTS : At baseline and months 4 , 9 , 12 , and 16 , aerobic capacity ( VO2max ) was measured by indirect calorimetry , BW by digital scale , and fat weight and fat-free weight by hydrostatic weighing . RESULTS : Aerobic capacity ( ml kg−1 min−1 ) increased ( P<0.05 ) from baseline ( 39.2±5.2 , mean±s.d . ) to 9 months ( 48.8±4.3 ) in exercising men as well as women ( 32.8±4.2–39.6±5.5 ) with no significant changes occurring at 12 or 16 months . From baseline to 9 months BW ( 94.0±12.6–88.7±9.7 kg ) and fat weight ( 26.8±6.8–21.8±4.5 kg ) significantly decreased in exercising men with no changes occurring at 12 or 16 months . There were no changes in fat-free weight across the 16 months for exercising men or for BW or composition in exercising women . Further , there were no significant changes for the control men for aerobic capacity , BW , or body composition across 16 months . Women in the control group showed significant increases in weight of 2.9±5.5 kg and fat weight of 2.1±4.8 kg at 16 months only . CONCLUSIONS : We recommend that investigations that use exercise without diet as the stimulus for weight loss have at least a 9-month duration to provide sufficient time for the full effects to be realized , should such effects be present The present study examined the cardiovascular health effects of 16 weeks of recreational football training in untrained premenopausal women in comparison with continuous running training .  Fifty healthy women were matched and r and omized to a football ( FG , n=25 ) or a running ( RG , n=25 ) group and compared with a control group with no physical training ( CO , n=15 ) . Training was performed for 1 h twice a week . After 16 weeks , systolic and diastolic blood pressure was reduced ( P<0.05 ) in FG ( 7+/-2 and 4+/-1 mmHg ) and systolic blood pressure was lowered ( P<0.05 ) in RG ( 6+/-2 mmHg ) . After 16 weeks , resting heart rate was lowered ( P<0.05 ) by 5+/-1 bpm both in FG and RG , and maximal oxygen uptake was elevated ( P<0.05 ) by 15 % in FG and by 10 % in RG ( 5.0+/-0.7 and 3.6+/-0.6 mL/min/kg , respectively ) . Total fat mass decreased ( P<0.05 ) by 1.4+/-0.3 kg in FG and by 1.1+/-0.3 kg in RG . After 16 weeks , pulse pressure wave augmentation index ( -0.9+/-2.5 vs 4.2+/-2.4 % ) , skeletal muscle capillarization ( 2.44+/-0.15 vs 2.07+/-0.05 cap/fib ) and low-density lipoprotein/high-density lipoprotein cholesterol ratio were improved ( P<0.05 ) in FG , but not altered in RG . No changes were observed in CO . In conclusion , regular recreational football training has significant favorable effects on the cardiovascular risk profile in untrained premenopausal women and is at the least as efficient as continuous running The animal model of exercise-induced anorexia was employed in humans to develop a laboratory paradigm for study ing the acute effect of exercise on food intake .  Each of nine obese and nine nonobese women  exercised either strenuously ( 90 W ) or moderately ( 30 W ) on a cycle ergometer for 40 min or rested in the laboratory on each of 3 nonconsecutive days .  Intake of a liquefied test meal  ( 1.04 kcal/g ) eaten 15 min after exercise was significantly less after the strenuous ( 620 g ) than after the moderate ( 754 g ) exercise in the nonobese women but was no different after the two conditions ( 532 g after strenuous , 581 g after moderate ) in the obese women . Heart rate and energy expenditure were increased in proportion to the exercise by the same amount in both groups . The results demonstrate for the first time that food intake is reduced immediately after strenuous exercise in nonobese women , as it is in animals , and vali date the feasibility of this laboratory paradigm BACKGROUND It is not clear how decreased activity quantitatively affects energy balance ( EB ) in subjects feeding ad libitum . OBJECTIVE We assessed the effect of an imposed sedentary routine on appetite , energy intake ( EI ) , EB , and nutrient balance in lean men for 7 d. DESIGN Six men with a mean ( + /-SD ) age of 23.0 + /- 2.3 y , weight of 69.2 + /- 11.4 kg , and height of 1.76 + /- 0.07 m were each studied twice during a sedentary [ 1.4 x resting metabolic rate ( RMR ) ] and a moderately active ( 1.8 x RMR ) regimen . During each treatment , they resided in the whole-body indirect calorimeter for the 7 d and had ad libitum access to a medium-fat diet of constant , measurable composition . Meal size , frequency , and composition were continually monitored . Motivation to eat was recorded during waking hours . Subjects were weighed in light clothing each morning , and their weight was corrected to nude . RESULTS Energy expenditure was 9.7 and 12.8 MJ/d [ P < 0.01 ; SE of the difference between means ( SED ) = 0.41 ] during the sedentary and active regimens , respectively . EI was 13.5 and 14.4 MJ/d ( P = 0.463 , SED = 1.06 ) , respectively . There was no regimen effect on hunger , appetite , or body weight . By day 7 , cumulative EB was 26.3 and 11.1 MJ , respectively . CONCLUSIONS Reducing a level of physical activity from 1.8 to 1.4 x RMR can markedly affect EB . A sedentary routine does not induce a compensatory reduction of EI and leads to a significantly positive EB , most of which is stored as fat The study was aim ed at investigating if endurance training of moderate intensity and longer duration , intended to promote health rather than performance , evokes ultrastructural changes in skeletal muscle tissue comparable to those observed after high-intensity protocol s. Twenty healthy , middle-aged men enrolled in a 6-month , home-based jogging program of 120 min/wk at 75 % VO2max . Only 12 men showed a sufficient exercise adherence  over the 6 months ( > or = 60 min/wk on average ) and were included into statistical analysis . Their average training activity was 105 + /- 31 min/wk . The results revealed significant increases in VO2max ( + 8.4 % , p < 0.01 ) and submaximal power output ( + 18.1 % , p < 0.01 ) . Total mitochondrial volume density in M. vastus lateralis increased by 20 % ( p < 0.05 ) with a larger increase in subsarcolemmal volume compared to central volume ( 50 % vs 15 % ) . No changes in volume of intracellular lipid droplets , capillary density , capillary per fiber ratio , fiber mean cross-sectional area and muscle fiber type could be observed . Body composition analysis showed a decrease in trunk fat mass ( -7.3 % , p < 0.05 ) and an increase in trunk lean mass ( + 1.7 % , p < 0.05 ) , while changes in the legs were not significant . It can be concluded that a moderate-intensity , health oriented endurance training beneficially affected cardiovascular and muscle oxidation capacity as well as body composition in the trunk area . No adaptations in capillaries or lipid metabolism could be demonstrated . The results support the hypothesis of thresholds for induction of adaptation processes in muscle skeletal tissue depending on the intensity of the exercise stimulus BACKGROUND Obesity is a major health problem due , in part , to physical inactivity . The amount of activity needed to prevent weight gain is unknown . OBJECTIVE To determine the effects of different amounts and intensities of exercise training . DESIGN R and omized controlled trial ( February 1999-July 2002 ) . SETTING AND PARTICIPANTS Sedentary , overweight men and women ( aged 40 - 65 years ) with mild to moderate dyslipidemia were recruited from Durham , NC , and surrounding communities . INTERVENTIONS Eight-month exercise 
    Output:
    
The fitted model suggested that for a shorter study duration , lower energy compensation was observed in younger individuals with higher initial fat mass ( FM ) .
In contrast , higher energy compensation was noted for younger individuals with lower initial FM .
From 25 weeks onward , energy compensation was no longer different for these predictors .
Lower energy compensation occurs with short-term exercise , and a much higher level of energy compensation accompanies long-term exercise interventions