***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 
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    ***EXAMPLES*** 
    Input: Background : Capacity to exercise may not be fully restored in patients with heart failure even in the long term after ventricular assist device ( VAD ) implantation . The benefits of exercise training in patients with VAD are unknown . Design and methods : Fifteen patients , aged 38.3 ± 15.9 years , bridged to heart transplantation with left ventricular assist device or biventricular assist device were r and omized at a ratio of 2 : 1 to a  training group  ( TG , n = 10 ) or a control group ( n = 5 ) , 6.3 ± 4 months after implantation . Both the groups were advised to walk 30–45 min/day . TG also underwent moderate-intensity aerobic exercise using a bike or treadmill for 45 min , three to five times a week , combined with high-intensity inspiratory muscle training using a computer- design ed software to respiratory exhaustion , two to three times a week for 10 weeks . The patients were tested using cardiopulmonary exercise testing , 6-min walk test , spirometry and electronic pressure manometer for inspiratory muscle strength ( Pimax ) and endurance ( sustained Pimax ) measurement . Quality of life was assessed with the Minnesota Living with Heart Failure question naire . Results : TG improved peak oxygen consumption ( 19.3 ± 4.5 vs. 16.8 ± 3.7 ml/kg per min , P = 0.008 ) and VO2 at ventilatory threshold ( 15.1 ± 4.2 vs. 12 ± 5.6 ml/kg per min , P = 0.01 ) , whereas the ventilation/carbon dioxide slope decreased ( 35.9 ± 5.6 vs. 40 ± 6.5 , P = 0.009 ) . The 6-min walk test distance increased ( 527 ± 76 vs. 462 ± 88 m , P = 0.005 ) and quality of life was improved ( 38.2 ± 11.6 vs. 48.9 ± 12.8 , P = 0.005 ) , as well as Pimax ( 131.8 ± 33 vs. 95.5 ± 28cmH2O , P = 0.005 ) , sustained Pimax ( 484 ± 195 vs. 340 ± 193cmH2O/s/10 3 , P = 0.005 ) , and inspiratoty lung capacity ( 2.4 ± 0.9 vs. 1.7 ± 0.7 L , P = 0.008 ) were improved . No significant changes were noted in the control group . Conclusion : Our findings indicate that exercise training may improve the functional status of VAD recipients  even at a later period after implantation and thus , may have additional importance in cases of destination therapy PURPOSE Patients with chronic heart failure ( CHF ) report difficulty performing activities of daily living . To our knowledge , however , no study has directly measured performance in activities of daily living in these patients to systematic ally assess their level of physical disability . Moreover , the contribution of skeletal muscle weakness to physical disability in CHF remains unclear . Thus , we measured performance in activities of daily living in CHF patients and controls , its relationship to aerobic capacity and muscle strength , and the effect of resistance exercise training to improve muscle strength and physical disability . METHODS Patients and controls were assessed for performance in activities of daily living , self-reported physical function , peak aerobic capacity , body composition , and muscle strength before and after an 18-wk resistance training program . To remove the confounding effects of several disease-related factors ( muscle disuse , hospitalization , acute illness ) , we recruited controls with similar activity levels as CHF patients and tested patients > 6 months after any disease exacerbation/hospitalization . RESULTS Performance in activities of daily living was 30 % lower ( P < 0.05 ) in CHF patients versus controls and was related to both reduced aerobic capacity ( P < 0.001 ) and muscle strength ( P < 0.01 ) . Moreover , resistance training improved ( P < 0.05 to P < 0.001 ) physical function and muscle strength in patients and controls similarly , without altering aerobic capacity . CONCLUSIONS CHF patients are characterized by marked physical disability compared with age- and physical activity-matched controls , which is related to reduced aerobic capacity and muscle strength . CHF patients respond to resistance training with normal strength/functional adaptations . Our results support muscle weakness as a determinant of physical disability in CHF and show that interventions that increase muscle strength  ( resistance training ) reduce physical disability CONTEXT Guidelines recommend that exercise training be considered for medically stable out patients with heart failure . Previous studies have not had adequate statistical power to measure the effects of exercise training on clinical outcomes . OBJECTIVE To test the efficacy and safety of exercise training among patients with heart failure . DESIGN , SETTING , AND PATIENTS Multicenter , r and omized controlled trial of 2331 medically stable out patients with heart failure and reduced ejection fraction . Participants in Heart Failure : A Controlled Trial Investigating Outcomes of Exercise Training ( HF-ACTION ) were r and omized from April 2003 through February 2007 at 82 centers within the United States , Canada , and France ; median follow-up was 30 months . INTERVENTIONS Usual care plus aerobic exercise training , consisting of 36 supervised sessions followed by home-based training , or usual care alone . MAIN OUTCOME MEASURES Composite primary end point of all-cause mortality or hospitalization and prespecified secondary end points of all-cause mortality , cardiovascular mortality or cardiovascular hospitalization , and cardiovascular mortality or heart failure hospitalization . RESULTS The median age was 59 years , 28 % were women , and 37 % had New York Heart Association class III or IV symptoms . Heart failure etiology was ischemic in 51 % , and median left ventricular ejection fraction was 25 % . Exercise adherence decreased from a median of 95 minutes per week during months 4 through 6 of follow-up to 74 minutes per week during months 10 through 12 . A total of 759 patients ( 65 % ) in the exercise training group died or were hospitalized compared with 796 patients ( 68 % ) in the usual care group ( hazard ratio [ HR ] , 0.93 [ 95 % confidence interval { CI } , 0.84 - 1.02 ] ; P = .13 ) . There were nonsignificant reductions in the exercise training group for mortality ( 189 patients [ 16 % ] in the exercise training group vs 198 patients [ 17 % ] in the usual care group ; HR , 0.96 [ 95 % CI , 0.79 - 1.17 ] ; P = .70 ) , cardiovascular mortality or cardiovascular hospitalization ( 632 [ 55 % ] in the exercise training group vs 677 [ 58 % ] in the usual care group ; HR , 0.92 [ 95 % CI , 0.83 - 1.03 ] ; P = .14 ) , and cardiovascular mortality or heart failure hospitalization ( 344 [ 30 % ] in the exercise training group vs 393 [ 34 % ] in the usual care group ; HR , 0.87 [ 95 % CI , 0.75 - 1.00 ] ; P = .06 ) . In prespecified supplementary analyses adjusting for highly prognostic baseline characteristics , the HRs were 0.89 ( 95 % CI , 0.81 - 0.99 ; P = .03 ) for all-cause mortality or hospitalization , 0.91 ( 95 % CI , 0.82 - 1.01 ; P = .09 ) for cardiovascular mortality or cardiovascular hospitalization , and 0.85 ( 95 % CI , 0.74 - 0.99 ; P = .03 ) for cardiovascular mortality or heart failure hospitalization . Other adverse events were similar between the groups . CONCLUSIONS In the protocol -specified primary analysis , exercise training result ed in nonsignificant reductions in the primary end point of all-cause mortality or hospitalization and in key secondary clinical end points . After adjustment for highly prognostic predictors of the primary end point , exercise training was associated with modest significant reductions for both all-cause mortality or hospitalization and cardiovascular mortality or heart failure hospitalization . TRIAL REGISTRATION clinical trials.gov Identifier : NCT00047437 OBJECTIVE Newer generation left ventricular assist devices ( LVADs ) are established for long-term support . The aim of this multi-modal intervention was to improve the body weight , exercise tolerance and psychosocial status in out patients on long-term LVAD support . METHODS Seventy patients participated in this non-r and omized intervention study [ intervention group ( IGr ) n = 34 ; control group ( CGr ) n = 36 ] over 18 months ( T1-T4 ) ; the baseline sample characteristics showed no differences between groups . Dietary counselling and weight management intervention was performed by a dietician based on a specific algorithm . Physical reconditioning followed a home ergometry protocol and was supplemented by psychosocial counselling . The outcomes were measured based on the body mass index ( BMI ) , cardiopulmonary exercise testing and self-report [ hospital anxiety and depression scale ( HADS ) , SF-36 ] . RESULTS The intervention showed a strong positive effect on nutrition and weight management [ 95 % confidence interval ( CI ) : -0.71 - 0.69 ; effect size ( ES ) : 0.907 ; P = 0.02 ) ] , result ing in the normal BMI ( kg/m(2 ) ) values in the IGr ( T1 : 24.0 ± 0.6 ; T4 : 24.5 ± 1.1 ; P = 0.35 ) compared with a significant BMI increase in the CGr ( T1 : 23.8 ± 0.6 ; T4 : 29.7 ± 0.8 ; P = 0.05 ) . Significant differences appeared regarding exercise tolerance ( VO(2)max/% predicted ) in favour of IGr patients ( IGr : 69 ± 2.9 ; CGr 62 ± 3.7 ; P = 0.04 ) . This increase was reflected by patients ' self-reporting based on the SF-36 physical component score ( IGr : P = 0.04 ; CGr : P = 0.54 ) . SF-36 psychosocial component scores showed no changes for both groups . However , CGr showed a tendency for increased anxiety scores relative to their counterparts ( IGr : 4.95 ± 0.4 ; CGr : 6.6 ± 0.9 ; P = 0.03 ) . CONCLUSIONS IGr patients showed a strong benefit from a multi-modal intervention , including dietary counselling , controlled exercise and psychosocial support . Dietary counselling holds potential to prevent obesity in this patient population Twenty-five patients ( aged 62 + /- 2 years ) with stable , moderate to severe ischemic congestive heart failure ( CHF ) ( New York Heart Association class II/III : 15/10 ; ejection fraction 21.6 + /- 2 % ; and peak oxygen uptake 13.6 + /- 0.7 ml/kg/min ) were studied to evaluate the ability of different methods to characterize autonomic tone in chronic CHF . Sympathovagal balance was assessed by : ( 1 ) heart rate variability in the time domain , assessed by the SD of RR intervals ; ( 2 ) heart rate variability in the frequency domain , assessed by low- ( 0.03 to 0.14 Hz ) and high- ( 0.18 to 0.40 Hz ) frequency components of heart rate variability by autoregressive power spectral analysis ; ( 3 ) 24-hour , daytime and nighttime heart rate ; ( 4 ) submaximal heart rate during upright bicycle exercise , with respiratory gas analysis to obtain  peak oxygen uptake ; and ( 5 ) radiolabeled norepinephrine spillover . These methods did not correlate , with the exception of day and nighttime heart rate ( r = 0.74 ; p < 0.001 ) and the expected inverse correlation between low and high frequency ( r = -0.92 ; p < 0.001 ) . No method correlated significantly with peak oxygen uptake , exercise tolerance or ejection fraction . After 8 weeks of physical training at home , all methods showed improvement in autonomic balance : increases in SD of RR intervals ( + 21 % ; p < 0.02 ) and high frequency ( + 41 % ; p < 0.007 ) , and decreases in low frequency ( -19 % ; p < 0.002 ) , low-/high-frequency ratio ( -48 % ; p < 0.03 ) , norepinephrine spillover ( -28.9 % ; p < 0.03 ) , 24-hour heart rate ( -2.7 % ; p < 0.005 ) and submaximal heart rate ( -10.8 % ; p < 0.01 ) . ( ABSTRACT TRUNCATED AT 250 WORDS BACKGROUND Patients with advanced heart failure have improved survival rates and quality of life when treated with implanted pulsatile-flow left ventricular assist devices as compared with medical therapy . New continuous-flow devices are smaller and may be more durable than the pulsatile-flow devices . METHODS In this r and omized trial , we enrolled patients with advanced heart failure who were ineligible for transplantation , in a 2: 
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Our systematic review suggests supervised ET has an inconsistent effect on exercise capacity and QoL when compared to control groups undergoing usual care .
These results suggest that supervised ET is safe and can improve patient outcomes  in LVAD patients when compared to the usual care