human
***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: Examines types of social support that best predicts adherence at different time points during a 1-year endurance exercise program in 269 women and men ages 50 to 65 years . Results indicate that social support had similar effects on exercise participation for women and men , and support specific to exercise was a better predictor of exercise adherence than general social support . A preference for receiving a lesser amount of initial support from exercise staff was the strongest social support-related predictor of exercise adherence during the initial 6 months of the program . Support currently received from family and friends and exercise staff at Month 6 was found to be the strongest predictor of adherence during Months 7 to 12 . Format of exercise  was also a strong predictor of exercise adherence with home-based programs related to greater adherence . Additionally , divorced nonsmokers appear to be at increased risk for poor early exercise adherence and should be targeted in interventions to promote exercise participation BACKGROUND Project ACTIVE was a r and omized clinical trial comparing two physical activity interventions , lifestyle and traditional structured exercise . The two interventions were evaluated and compared in terms of cost effectiveness and ability to enhance physical activity among sedentary adults . DESIGN This was a r and omized clinical trial . SETTING / PARTICIPANTS The study included 235 sedentary but healthy community-dwelling adults . INTERVENTION A center-based lifestyle intervention that consisted of behavioral skills training was compared to a structured exercise intervention that included supervised , center-based exercise . MAIN OUTCOME MEASURES The main outcome measures of interest included cost , cardiorespiratory fitness , and physical activity . RESULTS Both interventions were effective in increasing physical activity and fitness . At 6 months , the costs of the lifestyle and structured interventions were , respectively , $ 46.53 and $ 190.24 per participant per month . At 24 months these costs were $ 17.15 and $ 49.31 per participant per month . At both 6 months and 24 months , the lifestyle intervention was more cost-effective than the structured intervention for most outcomes measures . CONCLUSIONS A behaviorally-based lifestyle intervention approach in which participants are taught behavioral skills to increase their physical activity by integrating moderate-intensity physical activity into their daily lives is more cost-effective than a structured exercise program in improving physical activity and cardiorespiratory health . This study represents one of the first attempts to compare the efficiency of intervention alternatives for improving physical activity among healthy , sedentary adults Follow-up evaluation was conducted of 101 older men and women ( mean age = 67 + /- 5 years ) who had participated in a r and omized study of physiological and psychological effects of aerobic exercise . Eighty-five subjects completed the follow-up evaluation , and almost all of them ( 94 % ) reported continuing with physical activity , as assessed by a self-report measure . Total energy expenditure was calculated as an indicator of exercise maintenance , and energy expenditure at follow-up was predicted from measures of physiological functioning , psychological well-being , and cognitive functioning obtained at the conclusion of the structured exercise program . Greater cardiorespiratory endurance , faster psychomotor speed , and lower anxiety predicted exercise behavior at follow-up , accounting for 13 % of the variance in exercise behavior . Gender was not a significant predictor of exercise behavior Little is known about the predictors of maintenance in organized exercise programmes . The aim of this study was to investigate the behavioral predictors of maintenance of exercise participation in older adults , using an integrated social psychological model . To this end , we carried out a prospect i ve cohort study ( n = 1,725 ; age 50 years or older ) involving 10 different types of exercise programmes , with measurements at baseline and after 6 months . Predictors of intention to continue participating and the actual maintenance of  exercise participation in the exercise programme were assessed using a step-wise logistic regression model . Significant odds ratios ( ORs ) predicting the intention to continue with the  exercise programme  were found for female sex , younger age , being married , being a non-smoker , being in paid employment , having a positive attitude towards exercise and having a high self-efficacy at baseline . Significant ORs predicting actual maintenance of exercise participation  were short lapses , absence of lapses , high intention at baseline , high perceived quality of the programme , positive attitude at baseline and few risk situations at baseline . In order to promote maintenance of exercise participation for older adults , effort should be taken to prevent lapses , to help people cope with risk situations for lapses , to improve the attitude towards exercise participation and to improve the quality of the programme Signal detection methodology was used to identify the best combination of predictors of long-term exercise adherence  in 269 healthy , initially sedentary adults ages 50 - 65 years . Less educated individuals who were assigned to supervised home-based exercise of either higher or lower intensity and who were less stressed and less fit at baseline than other individuals had the greatest probability of successful adherence by the 2nd year . Overweight individuals assigned to a group-based exercise program were the least likely to be successful 2 years later . Predictors of short-term ( 1-year ) adherence were generally similar to predictors of 2-year adherence . Signal detection analysis may be useful for identifying subgroups of people at risk for underadherence who subsequently might be targeted for intervention Background . Counseling sedentary primary care patients can increase physical activity , but whether this approach will increase exercise and fitness in elderly adults with chronic diseases remains to be determined . Methods . After receiving individualized nurse counseling to begin a program of walking for health , 60- to 80-year-old primary care patients were r and omized to one of three levels of telephone contacts over 10 months : ( i ) 20 nurse-initiated calls , ( ii ) 10 nurse-initiated calls plus 10 motivational calls programmed through an automated phone calling system , or ( iii ) no program-initiated phone contacts .  Self-reported ( diary ) walking adherence was the primary outcome ; other activity , social support , health quality of life , and measured walking performance , mobility , and body mass index and girths were also assessed during the initiation ( months 1 - 6 ) and maintenance ( months 7 - 10 ) phases of the trial . Results . Average adherence for the 181 participants to the goal of walking at least 20 minutes on 3 or more days per week was 44 % for initiation and 42 % for maintenance . Participants receiving the combination of nurse-initiated personal and automated phone calls  walked significantly more frequently than those with no phone contacts . Fitness improved in all three groups ; changes were generally correlated with self-reported walking . Having a companion was associated with more frequent walking . Perceived quality of physical and mental health did not change . Conclusions . Simple and relatively inexpensive nurse contacts can motivate elderly primary care patients to walk for exercise , and this activity is associated with measurable health benefits The present study evaluated whether , and to what extent , the constructs implicated in the theory of planned behavior could predict behavioral intention to exercise and exercise-class attendance of older adults ( age 65 - 90 years ) already enrolled in a physical activity program . The study also evaluated whether including self-efficacy judgments might improve the predictive capacity of the model . Participants ( N = 1,095 ) were r and omly sample d Italian volunteers from exercise classes for older adults . First , they completed question naires assessing the above-mentioned constructs . Then , class attendance was recorded during the following 3 months . Results indicated a substantial correspondence between the model and the data . Perceived behavioral control and self-efficacy were the strongest predictors of behavioral intention , whereas attitudes and subjective norms only partially contributed to its prediction . The inclusion of self-efficacy improved the predictive capacity of the overall model . Finally , results showed a weak relation between behavioral intention and attendance rate in physical activity sessions This study examines dropout incidence , moment of dropout , and switching behavior in  organized exercise programs for seniors in the Netherl and s , as determined in a prospect i ve cohort study ( with baseline measurements at the start of the exercise program and follow-up after 6 months ; N = 1,725 , response rate 73 % ) . Participants were community-living individuals 50 + who participated in different forms of organized exercise programs .  The average dropout incidence was 0.15 per 6 months , which is lower than that for the general population . The dropout incidence and the timing of dropout differed substantially between the exercise programs . In total , 31 % of people who dropped out of one type of exercise program switched to another type of exercise .  The type of program and exercise had a strong effect on differences in this switching behavior . It is recommended that switching behavior be monitored in future studies OBJECTIVE To evaluate the effects of a lifestyle intervention and a structured exercise intervention on physical activity  in older adults . METHOD Participants were r and omly assigned to a lifestyle intervention ( n=60 ) , including an individualized home-based program supported by phone calls , or to  a structured intervention ( n=60 ) consisting of three weekly supervised sessions . Results were compared with a  control group ( n=66 ) .  Physical activity was measured with self-report question naires , pedometers , and accelerometers before the start ( pretest ) , at the end ( 11 months , posttest ) , and after 23 months ( follow-up ) . The study took place in Belgium from March 2004 until April 2006 . RESULTS At posttest , both intervention groups had significantly increased their total physical activity compared with the control group . At follow-up , the lifestyle group showed significantly larger increases in active transportation and total steps than the control and structured group respectively . There were no longer significant differences between the structured intervention and the control group . CONCLUSIONS The structured and lifestyle interventions were equally effective at the end of the intervention . One year after the intervention the lifestyle group maintained a significant increase in physical activity , which highlights the potential of lifestyle programs in the battle against inactivity in older adults This study prospect ively investigated the effects of major life events on subsequent  exercise adherence rates of individuals ( N = 173 ) participating in a 2-year , r and omized , controlled clinical trial of 3 different exercise conditions ( higher-intensity home-based ; lower-intensity home-based ; and higher-intensity class-based ) . For 3 of 4 6-month exercise-adherence periods , an analysis of variance indicated a significant main effect ( p < .05 ) for major life events . Compared with participants reporting 0 or 1 major life event ,  exercise adherence in the maintenance phase was significantly lower for those reporting 3 or 4 major life events regardless of the exercise condition . No significant life-event-exercise-adherence relationship was found in the adoption phase of exercise participation ( i.e. , Months 1 to 6 ) . The deleterious effect of life events emphasizes the importance of instruction regarding how to prepare for high-risk situations that can lead to missed exercise sessions or to program attrition Objectives . To investigate the relationships among self-efficacy , changes in self-efficacy , past exercise participation , future exercise adherence , and exercise program format . Methods . Two-year r and omized trial involving subjects ( n = 63 ) participating in an aerobic exercise program .  Subjects were r and omly assigned to one of three exercise conditions : higher-intensity home-based exercise , higher-intensity class-based exercise , or lower-intensity home-based exercise . Results . Results indicated that baseline self-efficacy and exercise format had significant ( p < .02 ) , independent effects on adherence during the adoption and early maintenance phases of exercise behavior . In contrast , in predicting long-term exercise program maintenance , a significant ( p < .05 ) self-efficacy X exercise format interaction indicated that self-efficacy predicted adherence only in the supervised home-based exercise conditions . Results also suggest that baseline self-efficacy , independent of the effect of past adherence , significantly ( p < .03 ) predicted exercise adherence during the adoption phase , but not early maintenance phase , of exercise behavior . Finally , adherence change during the adoption phase of exercise behavior significantly ( p < .04 ) predicted Year-one levels of self-efficacy even after adjusting far the effect of baseline self-efficacy . Conclusions . These results suggest that exercise program format as well as an individual 's initial cognitive and behavioral experiences in an exercise program play significant roles in determining exercise adherence This study examined whether psychological , physiological , and health and lifestyle measures were associated with adherence to a structured exercise program for older women . Women aged " 60 to 85 years ( N = 102 ) , " r and omly recruited from the community , were assessed on these measures before and after a 12-month exercise trial .  Sixty-nine women completed the trial , and 54 continued participation after the trial for at least 6 months . Adherence was examined at various stages during the trial . Multiple regression analysis revealed that reduced muscle strength , slow reaction time , and psychoactive drug use explained most of the variance in adherence during the trial . In contrast , muscle strength , reasoning ability , depression , and self-reported improvement in strength best predicted continued participation after the trial . The findings have implication s for community-based exercise programs and research trials CONTEXT Participation in regular physical activity is recognized as one of the most important health behaviors associated with the prevention of chronic disease and the promotion of health and well-being among the elderly . Although a number of cross-sectional studies have reported predictors of physical activity participation , few studies have assessed changes in intervention-related mediators associated with physical activity adherence in the elderly . OBJECTIVE The purpose of this study was to compare the relative abilities of cognitive mediating variables ( i.e. , self-efficacy beliefs and outcome expectancies/realizations ) versus a social mediating variable ( i.e. , exercise-related social support ) to examine mediators of a telephone-based , exercise-counseling intervention on exercise adherence during months 7 to 12 of an exercise intervention . METHOD Participants were 103 community-dwelling , healthy , sedentary , older adults ( 67 women and 36 men ) .  Self-efficacy for exercise 
    Output:
    
agent
Due to lack of high quality studies and often only one manuscript reporting on a particular determinant , we concluded " insufficient evidence " for most associations between determinants and physical activity or exercise .
***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: Examines types of social support that best predicts adherence at different time points during a 1-year endurance exercise program in 269 women and men ages 50 to 65 years . Results indicate that social support had similar effects on exercise participation for women and men , and support specific to exercise was a better predictor of exercise adherence than general social support . A preference for receiving a lesser amount of initial support from exercise staff was the strongest social support-related predictor of exercise adherence during the initial 6 months of the program . Support currently received from family and friends and exercise staff at Month 6 was found to be the strongest predictor of adherence during Months 7 to 12 . Format of exercise  was also a strong predictor of exercise adherence with home-based programs related to greater adherence . Additionally , divorced nonsmokers appear to be at increased risk for poor early exercise adherence and should be targeted in interventions to promote exercise participation BACKGROUND Project ACTIVE was a r and omized clinical trial comparing two physical activity interventions , lifestyle and traditional structured exercise . The two interventions were evaluated and compared in terms of cost effectiveness and ability to enhance physical activity among sedentary adults . DESIGN This was a r and omized clinical trial . SETTING / PARTICIPANTS The study included 235 sedentary but healthy community-dwelling adults . INTERVENTION A center-based lifestyle intervention that consisted of behavioral skills training was compared to a structured exercise intervention that included supervised , center-based exercise . MAIN OUTCOME MEASURES The main outcome measures of interest included cost , cardiorespiratory fitness , and physical activity . RESULTS Both interventions were effective in increasing physical activity and fitness . At 6 months , the costs of the lifestyle and structured interventions were , respectively , $ 46.53 and $ 190.24 per participant per month . At 24 months these costs were $ 17.15 and $ 49.31 per participant per month . At both 6 months and 24 months , the lifestyle intervention was more cost-effective than the structured intervention for most outcomes measures . CONCLUSIONS A behaviorally-based lifestyle intervention approach in which participants are taught behavioral skills to increase their physical activity by integrating moderate-intensity physical activity into their daily lives is more cost-effective than a structured exercise program in improving physical activity and cardiorespiratory health . This study represents one of the first attempts to compare the efficiency of intervention alternatives for improving physical activity among healthy , sedentary adults Follow-up evaluation was conducted of 101 older men and women ( mean age = 67 + /- 5 years ) who had participated in a r and omized study of physiological and psychological effects of aerobic exercise . Eighty-five subjects completed the follow-up evaluation , and almost all of them ( 94 % ) reported continuing with physical activity , as assessed by a self-report measure . Total energy expenditure was calculated as an indicator of exercise maintenance , and energy expenditure at follow-up was predicted from measures of physiological functioning , psychological well-being , and cognitive functioning obtained at the conclusion of the structured exercise program . Greater cardiorespiratory endurance , faster psychomotor speed , and lower anxiety predicted exercise behavior at follow-up , accounting for 13 % of the variance in exercise behavior . Gender was not a significant predictor of exercise behavior Little is known about the predictors of maintenance in organized exercise programmes . The aim of this study was to investigate the behavioral predictors of maintenance of exercise participation in older adults , using an integrated social psychological model . To this end , we carried out a prospect i ve cohort study ( n = 1,725 ; age 50 years or older ) involving 10 different types of exercise programmes , with measurements at baseline and after 6 months . Predictors of intention to continue participating and the actual maintenance of  exercise participation in the exercise programme were assessed using a step-wise logistic regression model . Significant odds ratios ( ORs ) predicting the intention to continue with the  exercise programme  were found for female sex , younger age , being married , being a non-smoker , being in paid employment , having a positive attitude towards exercise and having a high self-efficacy at baseline . Significant ORs predicting actual maintenance of exercise participation  were short lapses , absence of lapses , high intention at baseline , high perceived quality of the programme , positive attitude at baseline and few risk situations at baseline . In order to promote maintenance of exercise participation for older adults , effort should be taken to prevent lapses , to help people cope with risk situations for lapses , to improve the attitude towards exercise participation and to improve the quality of the programme Signal detection methodology was used to identify the best combination of predictors of long-term exercise adherence  in 269 healthy , initially sedentary adults ages 50 - 65 years . Less educated individuals who were assigned to supervised home-based exercise of either higher or lower intensity and who were less stressed and less fit at baseline than other individuals had the greatest probability of successful adherence by the 2nd year . Overweight individuals assigned to a group-based exercise program were the least likely to be successful 2 years later . Predictors of short-term ( 1-year ) adherence were generally similar to predictors of 2-year adherence . Signal detection analysis may be useful for identifying subgroups of people at risk for underadherence who subsequently might be targeted for intervention Background . Counseling sedentary primary care patients can increase physical activity , but whether this approach will increase exercise and fitness in elderly adults with chronic diseases remains to be determined . Methods . After receiving individualized nurse counseling to begin a program of walking for health , 60- to 80-year-old primary care patients were r and omized to one of three levels of telephone contacts over 10 months : ( i ) 20 nurse-initiated calls , ( ii ) 10 nurse-initiated calls plus 10 motivational calls programmed through an automated phone calling system , or ( iii ) no program-initiated phone contacts .  Self-reported ( diary ) walking adherence was the primary outcome ; other activity , social support , health quality of life , and measured walking performance , mobility , and body mass index and girths were also assessed during the initiation ( months 1 - 6 ) and maintenance ( months 7 - 10 ) phases of the trial . Results . Average adherence for the 181 participants to the goal of walking at least 20 minutes on 3 or more days per week was 44 % for initiation and 42 % for maintenance . Participants receiving the combination of nurse-initiated personal and automated phone calls  walked significantly more frequently than those with no phone contacts . Fitness improved in all three groups ; changes were generally correlated with self-reported walking . Having a companion was associated with more frequent walking . Perceived quality of physical and mental health did not change . Conclusions . Simple and relatively inexpensive nurse contacts can motivate elderly primary care patients to walk for exercise , and this activity is associated with measurable health benefits The present study evaluated whether , and to what extent , the constructs implicated in the theory of planned behavior could predict behavioral intention to exercise and exercise-class attendance of older adults ( age 65 - 90 years ) already enrolled in a physical activity program . The study also evaluated whether including self-efficacy judgments might improve the predictive capacity of the model . Participants ( N = 1,095 ) were r and omly sample d Italian volunteers from exercise classes for older adults . First , they completed question naires assessing the above-mentioned constructs . Then , class attendance was recorded during the following 3 months . Results indicated a substantial correspondence between the model and the data . Perceived behavioral control and self-efficacy were the strongest predictors of behavioral intention , whereas attitudes and subjective norms only partially contributed to its prediction . The inclusion of self-efficacy improved the predictive capacity of the overall model . Finally , results showed a weak relation between behavioral intention and attendance rate in physical activity sessions This study examines dropout incidence , moment of dropout , and switching behavior in  organized exercise programs for seniors in the Netherl and s , as determined in a prospect i ve cohort study ( with baseline measurements at the start of the exercise program and follow-up after 6 months ; N = 1,725 , response rate 73 % ) . Participants were community-living individuals 50 + who participated in different forms of organized exercise programs .  The average dropout incidence was 0.15 per 6 months , which is lower than that for the general population . The dropout incidence and the timing of dropout differed substantially between the exercise programs . In total , 31 % of people who dropped out of one type of exercise program switched to another type of exercise .  The type of program and exercise had a strong effect on differences in this switching behavior . It is recommended that switching behavior be monitored in future studies OBJECTIVE To evaluate the effects of a lifestyle intervention and a structured exercise intervention on physical activity  in older adults . METHOD Participants were r and omly assigned to a lifestyle intervention ( n=60 ) , including an individualized home-based program supported by phone calls , or to  a structured intervention ( n=60 ) consisting of three weekly supervised sessions . Results were compared with a  control group ( n=66 ) .  Physical activity was measured with self-report question naires , pedometers , and accelerometers before the start ( pretest ) , at the end ( 11 months , posttest ) , and after 23 months ( follow-up ) . The study took place in Belgium from March 2004 until April 2006 . RESULTS At posttest , both intervention groups had significantly increased their total physical activity compared with the control group . At follow-up , the lifestyle group showed significantly larger increases in active transportation and total steps than the control and structured group respectively . There were no longer significant differences between the structured intervention and the control group . CONCLUSIONS The structured and lifestyle interventions were equally effective at the end of the intervention . One year after the intervention the lifestyle group maintained a significant increase in physical activity , which highlights the potential of lifestyle programs in the battle against inactivity in older adults This study prospect ively investigated the effects of major life events on subsequent  exercise adherence rates of individuals ( N = 173 ) participating in a 2-year , r and omized , controlled clinical trial of 3 different exercise conditions ( higher-intensity home-based ; lower-intensity home-based ; and higher-intensity class-based ) . For 3 of 4 6-month exercise-adherence periods , an analysis of variance indicated a significant main effect ( p < .05 ) for major life events . Compared with participants reporting 0 or 1 major life event ,  exercise adherence in the maintenance phase was significantly lower for those reporting 3 or 4 major life events regardless of the exercise condition . No significant life-event-exercise-adherence relationship was found in the adoption phase of exercise participation ( i.e. , Months 1 to 6 ) . The deleterious effect of life events emphasizes the importance of instruction regarding how to prepare for high-risk situations that can lead to missed exercise sessions or to program attrition Objectives . To investigate the relationships among self-efficacy , changes in self-efficacy , past exercise participation , future exercise adherence , and exercise program format . Methods . Two-year r and omized trial involving subjects ( n = 63 ) participating in an aerobic exercise program .  Subjects were r and omly assigned to one of three exercise conditions : higher-intensity home-based exercise , higher-intensity class-based exercise , or lower-intensity home-based exercise . Results . Results indicated that baseline self-efficacy and exercise format had significant ( p < .02 ) , independent effects on adherence during the adoption and early maintenance phases of exercise behavior . In contrast , in predicting long-term exercise program maintenance , a significant ( p < .05 ) self-efficacy X exercise format interaction indicated that self-efficacy predicted adherence only in the supervised home-based exercise conditions . Results also suggest that baseline self-efficacy , independent of the effect of past adherence , significantly ( p < .03 ) predicted exercise adherence during the adoption phase , but not early maintenance phase , of exercise behavior . Finally , adherence change during the adoption phase of exercise behavior significantly ( p < .04 ) predicted Year-one levels of self-efficacy even after adjusting far the effect of baseline self-efficacy . Conclusions . These results suggest that exercise program format as well as an individual 's initial cognitive and behavioral experiences in an exercise program play significant roles in determining exercise adherence This study examined whether psychological , physiological , and health and lifestyle measures were associated with adherence to a structured exercise program for older women . Women aged " 60 to 85 years ( N = 102 ) , " r and omly recruited from the community , were assessed on these measures before and after a 12-month exercise trial .  Sixty-nine women completed the trial , and 54 continued participation after the trial for at least 6 months . Adherence was examined at various stages during the trial . Multiple regression analysis revealed that reduced muscle strength , slow reaction time , and psychoactive drug use explained most of the variance in adherence during the trial . In contrast , muscle strength , reasoning ability , depression , and self-reported improvement in strength best predicted continued participation after the trial . The findings have implication s for community-based exercise programs and research trials CONTEXT Participation in regular physical activity is recognized as one of the most important health behaviors associated with the prevention of chronic disease and the promotion of health and well-being among the elderly . Although a number of cross-sectional studies have reported predictors of physical activity participation , few studies have assessed changes in intervention-related mediators associated with physical activity adherence in the elderly . OBJECTIVE The purpose of this study was to compare the relative abilities of cognitive mediating variables ( i.e. , self-efficacy beliefs and outcome expectancies/realizations ) versus a social mediating variable ( i.e. , exercise-related social support ) to examine mediators of a telephone-based , exercise-counseling intervention on exercise adherence during months 7 to 12 of an exercise intervention . METHOD Participants were 103 community-dwelling , healthy , sedentary , older adults ( 67 women and 36 men ) .  Self-efficacy for exercise 
    Output:
    