***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: PURPOSE Obesity increases risk for all-cause and breast cancer mortality and comorbidities in women who have been diagnosed and treated for breast cancer . The Exercise and Nutrition to Enhance Recovery and Good Health for You ( ENERGY ) study is the largest weight loss intervention trial among survivors of breast cancer to date . METHODS In this multicenter trial , 692 overweight/obese women who were , on average , 2 years since primary treatment for early-stage breast cancer were r and omly assigned to either a group-based behavioral intervention , supplemented with telephone counseling and tailored newsletters , to support weight loss or a less intensive control intervention and observed for 2 years . Weight and blood pressure were measured at 6 , 12 , 18 , and 24 months . Longitudinal mixed models were used to analyze change over time . RESULTS At 12 months , mean weight loss was 6.0 % of initial weight in the intervention group and 1.5 % in the control group ( P<.001 ) . At 24 months , mean weight loss in the intervention and control groups was 3.7 % and 1.3 % , respectively ( P<.001 ) . Favorable effects of the intervention on physical activity and blood pressure were observed . The weight loss intervention was more effective among women older than 55 years than among younger women . CONCLUSION A behavioral weight loss intervention can lead to clinical ly meaningful weight loss in overweight/obese survivors of breast cancer . These findings support the need to conduct additional studies to test methods that support sustained weight loss and to examine the potential benefit of intentional weight loss on breast cancer recurrence and survival IMPORTANCE Leisure-time physical activity has been associated with lower risk of heart-disease and all-cause mortality , but its association with risk of cancer is not well understood . OBJECTIVE To determine the association of leisure-time physical activity with incidence of common types of cancer and whether associations vary by body size and /or smoking . DESIGN , SETTING , AND PARTICIPANTS We pooled data from 12 prospect i ve US and European cohorts with self-reported physical activity ( baseline , 1987 - 2004 ) . We used multivariable Cox regression to estimate hazard ratios ( HRs ) and 95 % confidence intervals for associations of leisure-time physical activity with incidence of 26 types of cancer . Leisure-time physical activity  levels were modeled as cohort-specific percentiles on a continuous basis and cohort-specific results were synthesized by r and om-effects meta- analysis . Hazard ratios for high vs low levels of activity are based on a comparison of risk at the 90th vs 10th percentiles of activity . The data analysis was performed from January 1 , 2014 , to June 1 , 2015 . EXPOSURES Leisure-time physical activity of a moderate to vigorous intensity . MAIN OUTCOMES AND MEASURES Incident cancer during follow-up . RESULTS A total of 1.44 million participants ( median [ range ] age , 59 [ 19 - 98 ] years ; 57 % female ) and 186 932 cancers were included . High vs low levels of leisure-time physical activity were associated with lower risks of 13 cancers : esophageal adenocarcinoma ( HR , 0.58 ; 95 % CI , 0.37 - 0.89 ) , liver ( HR , 0.73 ; 95 % CI , 0.55 - 0.98 ) , lung ( HR , 0.74 ; 95 % CI , 0.71 - 0.77 ) , kidney ( HR , 0.77 ; 95 % CI , 0.70 - 0.85 ) , gastric cardia ( HR , 0.78 ; 95 % CI , 0.64 - 0.95 ) , endometrial ( HR , 0.79 ; 95 % CI , 0.68 - 0.92 ) , myeloid leukemia ( HR , 0.80 ; 95 % CI , 0.70 - 0.92 ) , myeloma ( HR , 0.83 ; 95 % CI , 0.72 - 0.95 ) , colon ( HR , 0.84 ; 95 % CI , 0.77 - 0.91 ) , head and neck ( HR , 0.85 ; 95 % CI , 0.78 - 0.93 ) , rectal ( HR , 0.87 ; 95 % CI , 0.80 - 0.95 ) , bladder ( HR , 0.87 ; 95 % CI , 0.82 - 0.92 ) , and breast ( HR , 0.90 ; 95 % CI , 0.87 - 0.93 ) . Body mass index adjustment modestly attenuated associations for several cancers , but 10 of 13 inverse associations remained statistically significant after this adjustment .  Leisure-time physical activity  was associated with higher risks of malignant melanoma ( HR , 1.27 ; 95 % CI , 1.16 - 1.40 ) and prostate cancer ( HR , 1.05 ; 95 % CI , 1.03 - 1.08 ) . Associations were generally similar between overweight/obese and normal-weight individuals . Smoking status modified the association for lung cancer but not other smoking-related cancers . CONCLUSIONS AND RELEVANCE Leisure-time physical activity was associated with lower risks of many cancer types . Health care professionals counseling inactive adults should emphasize that most of these associations were evident regardless of body size or smoking history , supporting broad generalizability of findings Exercise improves health in lymphoma patients but the determinants of adherence in this population are unknown . The purpose of this study is to examine predictors of exercise adherence in lymphoma patients . In a r and omized trial , 60 lymphoma patients were assigned to the  exercise group and asked to attend three supervised exercise sessions per week for 12 weeks . Baseline data were collected on demographic , medical , fitness , psychosocial , and motivational variables . Adherence was assessed by objective attendance . Adherence was 77.8 % and was significantly predicted by age ( β = 0.29 ; p = 0.016 ) and past exercise ( β = 0.27 ; p = 0.024 ) ; and borderline significantly predicted by previous treatments ( β = 0.22 ; p = 0.053 ) , body mass index ( β = −0.21 ; p = 0.076 ) , and smoking ( β = −0.19 ; p = 0.092 ) . Poorer exercise adherence  was experienced by lymphoma patients under age 40 , insufficiently active at baseline , previously treated with radiation therapy , overweight or obese , and smokers . Findings may facilitate the development of targeted interventions to improve exercise adherence in this understudied patient population Background : The Colorectal Cancer and Home-Based Physical Exercise ( CAN-HOPE ) trial compared the effects of a 16-week home-based exercise program to usual care on quality of life in colorectal cancer survivors . Purpose : In this study , we report the weekly exercise barriers from the exercise group . Methods : Participants r and omized to the exercise group ( N = 69 ) were asked to report their exercise on a weekly basis by telephone . Those participants not achieving the minimum weekly exercise prescription ( 3 times per week of 30 min of moderate intensity exercise ) were asked for a primary exercise barrier . Results : We obtained 1,073 ( 97.2 % ) weeks of adherence data out of a possible 1,104 ( i.e. , 69 × 16 ) . Participants did not meet the minimum exercise prescription in 39.2 % ( 421/1,073 ) of the weeks . We obtained an exercise barrier in 83.8 % ( 353/421 ) of these cases . Overall , participants reported 37 different exercise barriers ; the three most common were lack of time/too busy , nonspecific treatment side effects , and fatigue . The top 7 to 10 barriers accounted for 70 % to 80 % of all missed exercise weeks . Conclusions : These findings may have utility for promoting exercise in this population both inside and outside of clinical trials Background Exercise adherence is a challenge for breast cancer patients receiving chemotherapy but few studies have identified the key barriers . Purpose In this paper , we report the barriers to supervised exercise in breast cancer patients participating in a r and omized controlled trial . Methods Breast cancer patients initiating adjuvant chemotherapy ( N = 242 ) were r and omly assigned to usual care  ( n = 82 )  or supervised resistance  ( n = 82 ) or aerobic  ( n = 78 ) exercise . Participants r and omized to the two exercise groups ( n = 160 ) were asked to provide a reason for each missed exercise session . Results The two exercise groups attended 70.2 % ( 5,495/7,829 ) of their supervised exercise sessions and provided a reason for missing 89.5 % ( 2,090/2,334 ) of their unattended sessions . The 2,090 reasons represented 36 different barriers . Feeling sick ( 12 % ) , fatigue ( 11 % ) , loss of interest ( 9 % ) , vacation ( 7 % ) , and nausea/vomiting ( 5 % ) accounted for the most missed exercise sessions . Disease/treatment-related barriers ( 19 of the 36 barriers ) accounted for 53 % ( 1,102/2,090 ) of all missed exercise sessions . Demographic and medical variables did not predict the types of exercise barriers reported . Conclusions Barriers to supervised exercise in breast cancer patients receiving chemotherapy are varied but over half can be directly attributed to the disease and its treatments . Behavioral support programs need to focus on strategies to maintain exercise in the face of difficult treatment side effects Background Evidence from r and omized controlled trials is growing that exercise interventions are beneficial in cancer patients receiving allogeneic stem cell transplantation ( allo-HCT ) . However , information about adherence to exercise interventions and exercise contamination in control groups is lacking . This information is crucial for the interpretation of study results . We therefore examined the determinants of exercise adherence and contamination in different treatment periods during ( inpatient ) and after ( outpatient ) allo-HCT . Methods One hundred fifty-three patients scheduled for allo-HCT were r and omized to a 1-year partly supervised exercise intervention ( endurance and resistance exercise ) or to a control group . Adherence was assessed via exercise logs and contamination via question naires . Results Adherence varied between 66 % ( inpatient ) and 78 % ( outpatient ) in different treatment periods . During ( inpatient ) transplantation period , higher adherence was significantly associated with lower fatigue ( P = 0.004 ) and with having children at home ( P = 0.049 ) . Adherence after discharge was positively associated with endurance performance ( P = 0.003 ) ; higher adherence after day 100 was associated with exercise activity prior allo-HCT ( P = 0.010 ) and higher adherence after discharge ( P = 0.001 ) . Contamination among controls was high with 54 % and significantly associated with muscle strength ( P = 0.025 ) and fatigue ( P = 0.050 ) . Conclusion Exercise adherence in different treatment periods was determined by different variables , and contamination among controls was evident . These findings may have important implication s for correct interpretation of r and omized exercise intervention trials In this study , we examined correlates of adherence and contamination in a r and omized controlled trial ( RCT ) of exercise in cancer survivors using the theory of planned behavior and the Five Factor Model of personality ( FFM ) . We r and omly assigned cancer survivors in group psychotherapy classes to either a waiting-list control group ( n = 45 ) or a home-based , moderate intensity exercise program ( n = 51 ) . At baseline , participants completed  measures  of the theory of planned behavior , the FFM , past exercise , physical fitness , medical variables , and demographics . We then monitored exercise over a 10-week period by weekly self-reports . Hierarchical multiple regression analyses indicated that the independent predictors of overall RCT exercise across both conditions were past exercise ( β = .36 , p > .001 ) , assignment to experimental condition ( β = .34 , p > .001 ) , sex ( β = .30 , p > .001 ) , and intention ( β = .14 , p > .10 ) . For exercise adherence in the exercise condition , the independent predictors were sex ( β = .38 , p > .01 ) , extraversion ( β = .30 , p > .05 ) , normative beliefs ( β = -.27 , p > .05 ) , and perceived behavioral control ( β = .23 , p > .10 ) . Finally , the independent predictors of exercise contamination in the control condition were past exercise ( β = .70 , p > .001 ) , sex ( β = .20 , p > .05 ) , and intention ( β = .17 , p > .10 ) . We conclude that the correlates of exercise adherence and contamination differ in kind as well as in degree . Explanations for these findings and practical implication s for conducting exercise RCTs in this population are offered OBJECTIVE Only between 25 % and 50 % of patients invited to participate in clinical trial-based physical exercise programs during cancer treatment agree to do so . The purpose of this study was to identify factors associated significantly with the decision ( not ) to participate 
    Output:
    
The most prominent predictors of adherence  to exercise interventions were location of the rehabilitation center , extensive exercise history , high motivation for exercise , and fewer exercise limitations .