***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 —To assess the effects of exercise training on ventilatory function in chronic heart failure . Design —Observer blinded r and om allocation crossover training and detraining trial . Setting — Assessment in hospital based clinical laboratory ; training home based . Patients —22 patients with chronic heart failure ( New York Heart Association ( NYHA ) class II or III ) recruited from a tertiary referral centre . All finished the study . Intervention — Bicycle ergometer exercise for 20 minutes a day , five days a week for eight weeks at 70%–80 % of maximum heart rate . Main outcome measures —Exercise capacity on grade d incremental exercise test , minute ventilation , oxygen consumption and carbon dioxide output . Results —Peak work load increased from 96 W to 112 W and peak oxygen consumption from 14·1 ml`/kg/min to 15·4 ml/kg/min ( p < 0·01 ) . At submaximal workloads carbon dioxide excretion ( Vco2 ) and minute ventilation ( Vi ) decreased significantly ( p < 0·05 ) though oxygen consumption was unchanged . The relation between Vi and carbon dioxide excretion changed : the slope of the Vi to Vco2 plot decreased from 38·6 to 35·3 , indicating an improvement in overall ventilary efficiency . The instantaneous carbon dioxide ventilatory equivalent ( Vi/Vco2 ) decreased at submaximal workloads , and reached a lower mimimum value after training , indicating that optimum ventilatory performance improved . The exercise capacity of patients was related to the optimum ventilatory performance . It is suggested that this may in part be mediated through changes in skeletal muscles . Conclusion —Exercise training reduces the ventilatory abnormalities in chronic heart failure ; thus some of these changes may be due to physical deconditioning Heart failure is a debilitating disorder which limits exercise capacity and produces a poor quality of life . The present study was design ed to determine the effects of an exercise training program on patients with CHF NYHA functional class II-III , attributed to left ventricular systolic dysfunction and dilated left ventricle . Twenty-two ambulatory male patients with stable CHF were r and omised to a training ( n = 15 ) and a control group ( n = 7 ) . A symptom limited ramp cardiopulmonary exercise test with gas exchange analysis was performed at baseline after 4 and 8 weeks . The training group underwent an exercise training program at 50 % of peak oxygen uptake for eight weeks . The control group was not exercised . After 8 weeks , compared with baseline , there were statistically significant increase in peak oxygen uptake , peak workload , anaerobic threshold , oxygen pulse , RPP , ventilation and the duration of the test only in trained patients . The reduction in scores tested by the Minnesota Living with Heart Failure question naire ( p < 0.001 ) and Borg dyspnea rating score ( p < 0.001 ) reflect the reduction of symptoms and the improvement in health-related quality of life .  Carefully selected patients with moderate to severe CHF can achieve significant improvements of exercise capacity and quality of life with exercise training and can safely participate in a conditioning program AIMS Recent guidelines recommend regular exercise in the management of patients with chronic heart failure ( CHF ) . This study was design ed to compare the safety and efficacy of conventional bicycle exercise and functional electrical stimulation ( FES ) of the legs as forms of home-based exercise training for patients with stable CHF . METHODS AND RESULTS Forty-six patients ( 38 male ) with stable NYHA Class II/III heart failure underwent a 6-week training programme using either a bicycle ergometer or electrical stimulation of the quadriceps and gastrocnemius muscles . In the bike group , significant increases were seen in 6-min walk ( 44.6 m , 95 % confidence interval ( CI ) 29.3 - 60.9 m ) , treadmill exercise time ( 110 s , 95 % CI 72.2 - 148.0 s ) , maximum leg strength ( 5.32 kg , 95 % CI 3.18 - 7.45 kg ) , and quadriceps fatigue index ( 0.08 , 95 % CI 0.04 - 0.12 ) following training . In the stimulator group , similar significant increases were seen following training for 6-min walk ( 40.6 m , 95 % CI 28.2 - 53.0 m ) , treadmill exercise time ( 67 s , 95 % CI 11.8 - 121.8s ) , maximum leg strength ( 5.35 kg , 95 % CI 1.53 - 9.17 kg ) , and quadriceps fatigue index ( 0.10 , 95 % CI 0.04 - 0.17 ) . Peak VO(2)did not change in either group following training , indicating a low-intensity regime . Quality of life scores improved following training when the bicycle and stimulator groups were considered together , but not when considered separately ( -0.43 , 95 % CI -8.13 to -0.56 ) . CONCLUSIONS FES produces beneficial changes in muscle performance and exercise capacity in patients with CHF . Within this study , the benefits were similar to those observed following bicycle training . FES could be offered to patients with heart failure as an alternative to bicycle training as part of a home-based rehabilitation programme Systemic arterial compliance ( SAC ) makes an important contribution to cardiac afterload , and thus is a significant determinant of left ventricular work . Previous studies have suggested that arterial compliance may be reduced in patients with congestive heart failure ( CHF ) , and that SAC is increased after a 4-week exercise training programme in healthy , sedentary individuals . The present study aim ed to investigate the effects of an 8-week exercise training programme on arterial mechanical properties , left ventricular performance and quality of life in CHF patients . A total of 21 patients with NYHA class II or III CHF ( mean+/-S.D. age 55+/-13 years ) were r and omly allocated to either an 8-week exercise training group or a " usual lifestyle " control group .  SAC , as determined non-invasively using applanation tonometry and Doppler aortic velocimetry , increased from 0.57+/-0.11 to 0.77+/-0.14 arbitrary compliance units ( mean+/-S.E.M. ; P=0.01 ) in the exercise group , while no change occurred in the control group . Left ventricular structure and function was assessed by echocardiography , and these parameters were unchanged over the 8-week study period . Exercise training significantly increased exercise capacity , measured by a 6-min walking test ( 474+/-27 to 547+/-34 m ; P=0.008 ) . Quality of life , as assessed using the Minnesota Living with Heart Failure Evaluation , demonstrated a decrease in heart failure symptoms from 46+/-7 to 24+/-5 units ( P=0.01 ) following the exercise training programme . These data show that exercise training improves SAC in patients with CHF . The accompanying improvement in exercise capacity may be due , in part , to an improvement in arterial function In the six years from 1975 through 1980 , a total of 12 men died during jogging in the state of Rhode Isl and . The cause of death in 11 was coronary heart disease ( CHD ) . One man died of an acute gastrointestinal hemorrhage . The prevalence of  jogging  in the Rhode Isl and population was determined using a r and om-digit telephone survey . Among men aged 30 through 64 years , 7.4 % + /- 2.6 % ( mean + /- SEE ) reported jogging at least twice a week . The incidence of death during jogging for men of this age group was one death per year for every 7,620 joggers , or approximately one death per 396,000 man-hours of jogging . This rate is seven times the estimated death rate from CHD during more sedentary activities in Rhode Isl and and suggests that exercise contributes to sudden death in susceptible persons . The occurrence of only one death per 7,620 joggers per year demonstrates that the risk of exercise is small and suggests that the routine exercise testing of healthy subjects before exercise training in not justified AIMS Hydrotherapy , i.e. exercise in warm water , as a rehabilitation program has been considered potentially dangerous in patients with chronic heart failure ( CHF ) due to the increased venous return caused by the hydrostatic pressure . However , hydrotherapy has advantages compared to conventional training . We studied the applicability of an exercise programme in a temperature-controlled swimming pool , with specific reference to exercise capacity , muscle function , quality of life and safety . METHODS AND RESULTS Twenty-five patients with CHF ( NYHA II-III , age 72.1+/-6.1 ) were r and omised into either 8 weeks of hydrotherapy ( n=15 ) , or into a control group ( n=10 ) . The training program was well tolerated with no adverse events . Patients in the hydrotherapy group improved their maximal exercise capacity ( + 6.5 vs.-5.9 W , P=0.001 ) , isometric endurance in knee extension ( + 4 vs.-9 s , P=0.01 ) together with an improvement in the performance of heel-lift ( + 4 vs. -3 n.o . , P=<0.01 ) , shoulder abduction ( + 12 vs. -8 s , P=0.01 ) and shoulder flexion ( + 6 vs. + 4 , P=0.01 ) in comparison to patients in the control group . CONCLUSION Physical training in warm water was well tolerated and seems to improve exercise capacity as well as muscle function in small muscle groups in patients with CHF . This new approach broadens the variety of training regimes for older patients with CHF Background This study was design ed to determine the controlled effects of a short-term exercise rehabilitation program on patients with moderate-to-severe left ventricular dysfunction after a recent myocardial infa rct ion . Methods and Results Thirty-nine male patients 51 + 8 years old with a large anterior myocardial infa rct ion less than 10 weeks old were recruited for the study . The patients were r and omly assigned to either one of two training or control groups on the basis of their resting ejection fraction : training , less than 30 % ; control , less than 30 % ; training , 31–50%1 ; or control , 31–50 % . Patients were evaluated for filling pressures , radionuclide ventriculography , heart volume , echocardiography , and work capacity . Patients who underwent training participated in an intensive 4-week in-hospital exercise program , whereas the control patients were restricted to a minimal activity program . Results indicated that there were no significant improvements in resting , submaximal , and maximal hemodynamic measurements as a result of the program . Mean work capacity and peak oxygen consumption improved significantly in the less-than-30 % training group but was accompanied by a significant increase in mean pulmonary wedge pressure . Resting ejection fraction improved markedly in both less-than-30Q% training and control patients , but ejection fraction measures were not associated with work capacity . Training did not cause further deterioration in ventricular function . Conclusions It was concluded that in the present study , exercise training had little or no effect on hemodynamic measurements and that the training effects achieved in patients with left ventricular dysfunction are most likely due to corrected impaired vasodilation , not necessarily to cardiac function . The importance ofusing a control group in this type of study and the wide intefindividual variations in training responses are emphasized Benefit from exercise training programmes for patients with chronic heart failure has been demonstrated in relatively young ( mean age 60 years ) and predominantly male subjects . This study was undertaken to assess the effect of an exercise programme for older subjects more representative of the general heart failure population OBJECTIVES The aim of this study was to assess the effects of regular physical exercise on local inflammatory parameters in the skeletal muscle of patients with chronic heart failure ( CHF ) . BACKGROUND Inflammatory activation with increased serum cytokine levels and expression of inducible nitric oxide synthase ( iNOS ) in the myocardium and peripheral skeletal muscles has been described in CHF . METHODS Twenty male patients with stable CHF ( left ventricular ejection fraction 25 + /- 2 % ; age 54 + /- 2 years ) were r and omized to a training group ( n = 10 ) or a control group ( n = 10 ) . At baseline and after six months , serum sample s and vastus lateralis muscle biopsies were obtained . Serum tumor necrosis factor (TNF)-alpha , interleukin (IL)-6 , and IL-1-beta levels were measured by enzyme-linked immunosorbent assay , local cytokine , and iNOS expression by real-time polymerase chain reaction . RESULTS Exercise training improved peak oxygen uptake by 29 % in the training group ( from 20.3 + /- 1.0 to 26.1 + /- 1.5 ml/kg . min ; p < 0.001 vs. control group ) . While serum levels of TNF-alpha , IL-6 , and IL-1-beta remained unaffected by training , local skeletal muscle TNF-alpha decreased from 1.9 + /- 0.4 to 1.2 + /- 0.3 relative U ( p < 0.05 for change vs. control group ) , IL-6 from 71.3 + /- 16.5 to 41.3 + /- 8.8 relative U ( p < 0.05 vs. begin ) , and IL-1-beta from 2.7 + /- 1.1 to 1.4 + /- 0.6 relative U ( p = 0.02 vs. control group ) . Exercise training also reduced local iNOS expression by 52 % ( from 6.3 + /- 1.2 to 3.0 + /- 1.0 relative U ; p = 0.007 vs. 
    Output:
    
Exercise training is safe and effective in patients with heart failure .