***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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    Input: This study poses two questions : 1 ) is there an abnormality in isokinetic skeletal muscle strength and endurance in mild chronic obstructive pulmonary disease ( COPD ) ? and 2 ) what is the effect of a r and omized , controlled , 12 week hospital outpatient weight training programme in terms of skeletal muscle function and exercise tolerance ? Upper and lower limb isokinetic maximum and sustained muscle function were compared in 43 COPD patients ( age 49+/-11 yrs ) , mean forced expiratory volume in one second ( FEV1 ) 77+/-23 % pred and 52 healthy , sedentary subjects ( age 51 ( 10 ) yrs ) , mean FEV1 109+/-16 % pred . The 43 COPD patients were r and omly allocated into training ( n=26 ) and control ( n=17 ) groups . Isokinetic and isotonic muscle function , whole body endurance , maximal exercise capacity and lung function were measured . The COPD patients had reduced isokinetic muscle function ( with the exception of sustained upper limb strength ) as compared with healthy sedentary subjects . Muscle function improved after weight training in the COPD patients . Whole body endurance during treadmill walking also improved with no change in maximal oxygen consumption . A deficit in skeletal muscle function can be identified in patients with mild chronic obstructive pulmonary disease which can not be explained by factors such as hypoxaemia and malnutrition . Intervention with weight training is effective in countering this deficit which the authors conclude is probably due to muscle deconditioning Changes in health according to World Health Organization ’s International Classification of Functioning , Disability and Health ( ICF ) after four weeks of pulmonary rehabilitation ( PR ) were investigated . Gender differences in the response to PR , and the correlation between improvements in the two components of ICF ( Body functions and Activities and Participation ) were examined . Twenty-two men and 18 women with chronic obstructive pulmonary disease in Global Initiative for Chronic Obstructive Lung Disease ( GOLD ) stage II-IV attended in-patient , multidisciplinary PR consisting of endurance training four to five times/week at 70 % of peak work rate ( WRpeak ) , resistance training three to four times/week at 72 % of 15 repetitions maximum , educational sessions and individual counselling . The results were compared to those of 20 Chronic Obstructive Pulmonary Disease ( COPD ) patients included after the same criteria and investigated while waiting for admission to PR . In the rehabilitation group , we found significant improvements in health related quality of life ( HRQoL ) ( -7 units , St. George ’s Respiratory Question naire ) , arm ( 6 % ) and leg ( 15 % ) maximal voluntary contraction , peak oxygen uptake ( 6 % ) , WRpeak ( 60 % ) and treadmill endurance time ( 93 % ) . At iso-WR , ventilation and dyspnoea were significantly lower , but inspiratory capacity remained unchanged . Improvements in HRQoL correlated with increases in peak ventilation , but not in muscle strength or exercise capacity . Men improved their six-minute walking distance significantly in contrast to women . Clinical ly important improvements in HRQoL were found in two out of three of the men , and one out of three of the women . Four weeks of intensive PR generated significant health effects comparable to longer lasting programmes . Changes in exercise capacity and muscle strength were not related to improvements in HRQoL. The gender differences in the response to PR deserve attention in future studies PURPOSE The primary goal of pulmonary rehabilitation ( PR ) is for patients to achieve and maintain their maximum level of independence and functioning in the community . Traditional PR uses a predominantly aerobic/endurance approach to rehabilitation with little or no inclusion of exercises to increase strength . Few studies have investigated the impact of resistance training on PR despite growing evidence supporting its efficacy to improve physical function ( functional fitness ) in both healthy individuals and those with chronic disease . The purpose of this study was to investigate the effect of single-set resistance training on strength and functional fitness outcomes in PR patients . METHODS Twenty PR patients , 60 to 81 years old , were r and omly assigned to an 8-week endurance-based PR program ( ET ) or an ET plus resistance training program ( RT ) . RESULTS Strength increased in RT ( P < .05 ) and decreased in  ET for both upper and lower body . Functional fitness improved ( P < .05 ) in 5 of 7 tests for RT compared with 2 tests for ET . CONCLUSIONS Single set RT can elicit significant improvements in both strength and functional fitness , which is not obtained by traditional PR alone . Our results are comparable to other studies with similar outcomes using multiple-set RT protocol s. These findings may have important implication s for program design , application , and adherence in PR BACKGROUND PATIENTS : with chronic airflow obstruction are often limited by muscle fatigue and weakness . As exercise rehabilitation programmes have produced modest improvements at best a study was design ed to determine whether specific muscle training techniques are helpful . METHODS : Thirty four patients with chronic airflow limitation ( forced expiratory volume in one second ( FEV1 ) 38 % of predicted values ) were stratified for FEV1 to vital capacity ( VC ) ratio less than 40 % and arterial oxygen desaturation during exercise and r and omised to a  control or weightlifting training group . In the experimental group training was prescribed for upper and lower limb muscles as a percentage of the maximum weight that could be lifted once only . It was carried out three times a week for eight weeks . RESULTS : Three subjects dropped out of each group ; results in the remaining 14 patients in each group were analysed . Adherence in the training group was 90 % . In the trained subjects muscle strength and endurance time during cycling at 80 % of maximum power output increased by 73 % from 518 ( SE69 ) to 898 ( 95 ) s , with control subjects showing no change ( 506 ( 86 ) s before training and 479 ( 89 ) s after training ) . No significant changes in maximum cycle ergometer exercise capacity or distance walked in six minutes were found in either group . Responses to a chronic respiratory question naire showed significant improvements in dyspnoea and mastery of daily living activities in the trained group . CONCLUSIONS : Weightlifting training may be successfully used in patients with chronic airflow limitation , with benefits in muscle strength , exercise endurance , and subjective responses to some of the dem and s of daily living This r and omized , controlled study investigated the physiological effects of a specially design ed 12 week programme of isolated conditioning of peripheral skeletal muscle groups . The programme required minimal infrastructure in order to allow continued rehabilitation at home after familiarization within hospital . Forty eight patients , aged 40 - 72 yrs with chronic obstructive pulmonary disease ( COPD ) ( mean ( SD ) forced expiratory volume in one second ( FEV1 ) 61 (27)% of predicted normal ) were r and omly allocated into training ( n = 32 ) and control ( n = 16 ) groups . Physiological assessment s were performed before and after the 12 week study period , and included peripheral muscle endurance and strength , whole body endurance , maximal exercise capacity ( maximum oxygen consumption ( V'O2,max ) ) and lung function . The training group showed significant improvement in a variety of measures of upper and lower peripheral muscle performance , with no additional breathlessness . Whole body endurance measured by free arm treadmill walking increased by 6,372 ( 3,932 - 8,812 ) 3 ( p < 0.001 ) . Symptom-limited maximal V'O2 was unchanged . However , the training group showed a reduction in ventilatory equivalents for oxygen and carbon dioxide , both at peak exercise and at equivalent work rate ( Wmax ) . In summary , low intensity isolated peripheral muscle conditioning is well-tolerated , simple and easy to perform at home . The various physiological benefits should enable patients across the range of severity of chronic obstructive pulmonary disease to improve daily functioning PURPOSE Pulmonary rehabilitation programs are effective in patients with severe chronic obstructive pulmonary disease ( COPD ) in the short term , but their long-term effects are not known . We investigated the short- and long-term effects of a 6-month outpatient rehabilitation program in patients with severe COPD . SUBJECTS AND METHODS One hundred patients were r and omly assigned to receive either an exercise training program that included cycling , walking , and strength training ( n = 50 ) or usual medical care ( n = 50 ) . Thirty-four patients in the training group were evaluated after 6 months ( end of training ) , and 26 were evaluated after 18 months of follow-up . In the control group , 28 patients were evaluated at 6 months and 23 after 18 months . We measured pulmonary function , 6-minute walking distance , maximal exercise capacity , peripheral and respiratory muscle strength , and quality of life ( on a 20 to 140-point scale ) , and estimated the cost-effectiveness of the program . RESULTS At 6 months , the training group showed improvement in 6-minute walking distance [ mean difference ( training - control ) of 52 m ; 95 % confidence interval ( CI ) , 15 to 89 m ] , maximal work load ( 12 W ; 95 % CI , 6 to 19 W ) , maximal oxygen uptake ( 0.26 liters/min ; 95 % CI , 0.07 to 0.45 liters/min ) , quadriceps force ( 18 Nm ; 95 % CI , 7 to 29 Nm ) , inspiratory muscle force ( 11 cm H(2)O ; 95 % CI , 3 to 20 cm H(2)O ) , and quality of life ( 14 points ; 95 % CI , 6 to 21 points ; all P < 0.05 ) . At 18 months all these differences persisted ( P < 0.05 ) , except for inspiratory muscle strength . For 6-minute walking distance and quality of life , the differences between the training group and controls at 18 months exceeded the minimal clinical ly-important difference . CONCLUSION Among patients who completed the 6-month program , outpatient training result ed in significant and clinical ly relevant changes in 6-minute walking distance , maximal exercise performance , peripheral and respiratory muscle strength , and quality of life . Most of these effects persisted 18 months after starting the program The effects of endurance training on exercise capacity and health-related quality of life ( HRQL ) in chronic obstructive pulmonary disease ( COPD ) patients have been studied thoroughly , while resistance training has been rarely evaluated . This study investigated the effects of resistance training in comparison with endurance training in patients with moderate to severe COPD and peripheral muscle weakness ( isometric knee extension peak torque < 75 % predicted ) . Forty-eight patients ( age 64±8 yrs , forced expiratory volume in one second 38±17 % pred ) were r and omly assigned to resistance training ( RT , n=24 ) or endurance training ( ET , n=24 ) . The former consisted of dynamic strengthening exercises . The latter consisted of walking , cycling and arm cranking .  Respiratory and peripheral muscle force , exercise capacity , and HRQL were re-evaluated in all patients who completed the 12-week rehabilitation ( RT n=14 , ET n=16 ) . Statistically significant increases in knee extension peak torque ( RT 20±21 % , ET 42±21 % ) , maximal knee flexion force ( RT 31±39 % , ET 28±37 % ) , elbow flexion force ( RT 24±19 % , ET 33±25 % ) , 6-min walking distance ( 6MWD ) ( RT 79±74 m , ET 95±57 m ) , maximum workload ( RT 15±16 Watt , ET 14±13 Watt ) and HRQL ( RT 16±25 points , ET 16±15 points ) were observed . No significant differences in changes in HRQL and 6MWD were seen between the two treatments . Resistance training and endurance training have similar effects on peripheral muscle force , exercise capacity and health-related quality of life in chronic obstructive pulmonary disease patients with peripheral muscle weakness Dysfunction of the muscles of ambulation contributes to exercise intolerance in chronic obstructive pulmonary disease ( COPD ) . Men with COPD have high prevalence of low testosterone levels , which may contribute to muscle weakness . We determined effects of testosterone supplementation ( 100 mg of testosterone enanthate injected weekly ) with or without resistance training ( 45 minutes three times weekly ) on body composition and muscle function in 47 men with COPD ( mean FEV(1 ) = 40 % predicted ) and low testosterone levels ( mean = 320 ng/dl ) . Subjects were r and omized to 10 weeks of placebo injections + no training , testosterone injections + no training , placebo injections + resistance training , or testosterone injections + resistance training . Testosterone injections yielded a mean increase of 271 ng/dl in the nadir serum testosterone concentration ( to the middle of the normal range for young men ) . The lean body mass ( by dual-energy X-ray absorptiometry ) increase averaged 2.3 kg with testosterone alone and 3.3 kg with combined testosterone and resistance training ( p < 0.001 ) . Increase in one-repetition maximum leg press strength averaged 17.2 % with testosterone alone , 17.4 % with resistance training alone , and 26.8 % with testosterone + resistance training ( p < 0.001 ) . Interventions were well tolerated with no abnormal 
    Output:
    
Conclusions Based on findings from the meta- analysis , RT produces a clinical ly and statistically significant effect on respiratory function ( such as forced vital capacity ) and is therefore recommended in the management of COPD