***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 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 Decreased exercise capacity is the main factor restricting the daily life of patients with chronic congestive heart failure ( CHF ) . We performed a controlled , r and omized study to evaluate the effect of dynamic exercise training of moderate intensity on exercise capacity and gas exchange in patients with CHF . Twenty-seven patients with stable CHF , New York Heart Association ( NYHA ) functional class II and III , were r and omized to training ( n = 12 ) and control ( n = 15 ) groups . During a 3-month period , the training group underwent a supervised physical training program using a bicycle ergometer for 30 min 3 times a week at a load corresponding to 50 to 60 % of their peak oxygen consumption . Thereafter , they were advised to continue training at home for the next 3 months . The control group did not change their previous physical activity . A grade d maximal exercise test with respiratory gas analysis and an endurance test with constant submaximal workload were performed at baseline and after 3 and 6 months . The exercise endurance increased from 14.7 + /- 2.0 to 27.8 + /- 2.7 min ( p < 0.01 ) and the peak oxygen consumption tended to improve from 19.3 + /- 1.6 to 21.7 + /- 2.3 mL/kg/min ( p = 0.09 ) during the supervised training period . At submaximal workloads , minute ventilation was reduced by 16 % per se ( p < 0.01 ) and by 7 % in proportion to carbon dioxide production ( p < 0.05 ) . Oxygen consumption at the anaerobic threshold increased from 10.5 + /- 0.8 to 12.7 + /- 1.0 mL/kg/min ( p < 0.05 ) . The positive training effects were associated with an improvement in the NYHA functional class . The effects of supervised training were preserved during the home-based training period . The results indicate that physical training of moderate intensity significantly improves the exercise capacity and reduces the exaggerated ventilatory response to exercise , particularly at submaximal working levels in patients with CHF . This is associated with alleviation of symptoms OBJECTIVE : To examine the long-term benefits and safety of aerobic training in patients with chronic heart failure . DESIGN : Non-r and omised control trial with 52 weeks follow up . SETTING : Outpatient cardiac rehabilitation referral centre . PATIENTS : Patients with compensated chronic heart failure ( mean ( SD ) age 62 ( 6 ) years , New York Heart Association stage III , initial resting ejection fraction 22 (7)% ) . Experimental group of 17 men , 4 women ; control group 8 men , 1 woman . INTERVENTIONS : Experimental group : progressive , supervised aerobic walking programme for 52 weeks . Control group : st and ard medical treatment . MAIN OUTCOME MEASURES : Six-minute walk distance , progressive cycle ergometer test to subjective exhaustion , disease-specific quality of life question naire , and st and ard gamble test , all measured at entry , 4 , 8 , 12 , 16 , 26 , and 52 weeks . RESULTS : Control data showed no changes except a small trend to improved emotional function ( P = 0.02 at 12 weeks only ) . Fifteen of the 21 patients completed all 52 weeks of aerobic training ; two withdrew for non-cardiac reasons ( 16 , 52 weeks ) . Three were withdrawn because of worsening cardiac failure unrelated to their exercise participation ( 4 , 4 , 8 weeks ) , and one had a non-fatal cardiac arrest while shopping ( 16 weeks ) . Gains of cardiorespiratory function plateaued at 16 - 26 weeks , with 10 - 15 % improvement in six-minute walk , peak power output , and peak oxygen intake linked to gains in oxygen pulse and ventilatory threshold and reductions in resting heart rate . Marked improvements in quality of life followed a parallel course . CONCLUSIONS : Aerobic training is safe and beneficial in compensated chronic heart failure . Gains in aerobic function and quality of life persisted over a programme lasting 52 weeks This study examined the effect of a novel circuit weight training ( CWT ) program on cardiorespiratory fitness , muscular strength , and body composition in 13 patients with chronic heart failure ( CHF ) , using a prospect i ve r and omized crossover protocol . Peak exercise oxygen uptake ( VO(2 peak ) ) increased after the 8-wk CWT program ( 19 . 5 + /- 1.2 vs. 22.0 + /- 1.5 ml . kg(-1 ) . min(-1 ) , P < 0.01 ) , as did exercise test duration ( 15.2 + /- 0.9 vs. 18.0 + /- 1.1 min , P < 0 . 001 ) . Submaximal exercise heart rate was lower after training at 60 and 80 W ( 121 + /- 3 vs. 134 + /- 5 beats/min , P < 0.01 ) as was rate pressure product , whereas ventilatory threshold increased , from 52 + /- 3 to 58 + /- 3 % of VO(2 peak ) ( P < 0.05 ) . CWT also increased maximal isotonic voluntary contractile strength for seven different muscle groups , from 392 to 462 kg ( P = 0.001 ) . CWT , an exercise prescription specifically targeting peripheral abnormalities in CHF , improves functional capacity and muscular strength in these patients A new program of rehabilitation is less dem and ing on cardiac output than st and ard programs . Twenty-five patients with chronic heart failure ( ejection fraction [ EF ] : 0.26 + /- 0.10 ) were r and omized into 2 groups : a  control group with 13 patients and a  rehabilitation group of 12 patients . In the control group , 2 did not complete the study ( cancer , cardiac transplantation ) . For the 11 others , the different parameters studied were comparable at day 0 with group R and did not significantly change over 3 months outside of a spontaneous improvement in endurance performance by 22 % . In the rehabilitation group ( 40 sessions over 90 days ; specialized equipment ) there were no incidents . Tolerance was excellent ( heart rate during sessions less than 115 bpm ) and all functional parameters improved . Training did not modify the isotopic ejection fraction . The quality of life score increased respectively by 52 % ( p less than 0.0001 in comparison with the control group ) and by 63 % ( p less than 0.0001 ) ; 80 % of the patients requested that training be prolonged . The functional improvement obtained by purely peripheral effect had no adverse effect on the heart Background : Reduced heart pump function and skeletal muscle abnormalities are considered important determinants for the low physical exercise capacity in chronic heart failure . Because of reduced ventricular function , traditional physical rehabilitation may cause underperfusion and low local work intensity , thereby producing suboptimal conditions for skeletal muscle training AIMS Benefit from exercise training in heart failure has mainly been shown in men with ischaemic disease . We aim ed to examine the effects of exercise training in heart failure patients < or = 75 years old of both sexes and with various aetiology . METHODS AND RESULTS Fifty-four patients with stable mild-to-moderate heart failure were r and omized to exercise or control , and 49 completed the study ( 49 % > or = 65 years ; 29 % women ; 24 % non-ischaemic aetiology ; training , n = 22 ; controls , n = 27 ) . The exercise programme consisted of bicycle training at 80 % of maximal intensity over a period of 4 months . Improvements vs controls were found regarding maximal exercise capacity ( 6 + /- 12 vs -4 + /- 12 % [ mean + /- SD ] , P < 0.01 ) and global quality -of-life ( 2 [ 1 ] vs 0 [ 1 ] units [ median ¿ inter-quartile range ¿ ] , P < 0.01 ) , but not regarding maximal oxygen consumption or the dyspnoea-fatigue index . All of these four variables significantly improved in men with ischaemic aetiology compared with controls ( n = 11 ) . However , none of these variables improved in women with ischaemic aetiology ( n = 5 ) , or in patients with non-ischaemic aetiology ( n = 6 ) . The training response was independent of age , left ventricular systolic function , and maximal oxygen consumption . No training-related adverse effects were reported . CONCLUSION Supervised exercise training was safe and beneficial in heart failure patients < or = 75 years , especially in men with ischaemic aetiology . The effects of exercise training in women and patients with non-ischaemic aetiology should be further examined AIMS To assess whether a domiciliary programme of specific inspiratory muscle training in stable chronic heart failure results in improvements in exercise tolerance or quality of life . METHODS AND RESULTS We conducted a r and omized controlled trial of 8 weeks of inspiratory muscle training in 18 patients with stable chronic heart failure , using the Threshold trainer . Patients were r and omized either to a training group inspiring for 30 min daily at 30 % of maximum inspiratory mouth pressure , or to a control group of ' sham ' training at 15 % of maximum inspiratory mouth pressure .  Sixteen of the 18 patients completed the study .  Maximum inspiratory mouth pressure improved significantly in the training group compared with controls , by a mean ( SD ) of 25.4 ( 11.2 ) cmH2O ( P=0.04 ) . There were , however , no significant improvements in treadmill exercise time , corridor walk test time or quality of life scores in the trained group compared with controls . CONCLUSION Despite achieving a significant increase in inspiratory muscle strength , this trial of simple domiciliary inspiratory muscle training using threshold loading at 30 % of maximum inspiratory mouth pressure did not result in significant improvements in exercise tolerance or quality of life in patients with chronic heart failure Background Many secondary abnormalities in chronic heart failure ( CHF ) may reflect physical deconditioning . There has been no prospect i ve , controlled study of the effects of physical training on hemodynamics and 
    Output:
    
We conclude that short-term physical exercise training in selected subgroups of patients with CHF has physiological benefits and positive effects on quality of life .