***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: Abstract The evaluation of a 13-month maintenance program ( MP ) for 39 severe COPD patients with FEV1%pred 44(7)% who , as result of two different 8-week leg exercise training ( LET ) programs , one supervised at the hospital ( group S ; n = 20 ) and the other self-monitored ( SM ; n = 19 ) , had achieved different levels of exercise tolerance . After LET , patients in group S had a higher maximal oxygen uptake and endurance time than patients in the SM group [ O2max 1.43(0.30 ) l · min−1 ] vs l.25(0.27 ) l · min−1 and endurance-time 16(4 ) min vs 12 ( 5 ) min , respectively ) . During the MP patients were advised to walk vigorously at least 4 km/day , 4 times/wk . After the MP , while endurance time remained higher than at baseline , it had decreased ( p < 0.01 ) immediately after LET in both groups and no differences were evident between groups ( 11(4 ) min and 10(4 ) , respectively ) . In contrast , Chronic Respiratory Diseases Question naire scores , which had improved significantly after LET in both groups , remained high . Long-term effects of MP were independent of the training strategy or whether physiological improvements had been obtained with the initial LET . SM exercise programs do not seem capable of maintaining physiological improvements in exercise tolerance , though “ quality of life ” can be maintained Limited information is available regarding the physiological responses to different types of exercise training in patients with severe chronic obstructive pulmonary disease ( COPD ) . The aim of this study was two fold : firstly , to investigate the physiological response to training at 60 % of achieved peak load in patients with severe COPD ; and secondly to study the effects of interval ( I ) versus continuous ( C ) training in these patients . Twenty-one patients with COPD ( mean+/-SD forced expiratory volume in one second : 37+/-15 % of predicted , normoxaemic at rest ) were evaluated at baseline and after 8 weeks ' training . Patients were r and omly allocated to either I or C training . The training was performed on a cycle ergometer , 5 days a week , 30 min daily . The total work load was the same for both training programmes . C training result ed in a significant increase in oxygen consumption ( V'O2 ) ( 17 % , p<0.05 ) and a decrease in minute ventilation (V'E)/V'O2 ( p<0.01 ) and V'E/carbon dioxide production ( V'CO2 ) ( p<0.05 ) at peak exercise capacity , while no changes in these measures were observed after interval training . During submaximal exercise a significant decrease was observed in lactic acid production , being most pronounced in the C-trained group ( -31 % , p<0.01 versus -20 % , p<0.05 ) . Only in the I-trained group did a significant increase in peak work load ( 17 % , p<0.05 ) and a decrease in leg pain ( p<0.05 ) occur . Training did not result in a significant improvement in lung function , but maximal inspiratory mouth pressure increased in both groups by 10 % ( C : p<0.05 ) and 23 % ( I : p<0.01 ) . The present study shows a different physiological response pattern to interval or continuous training in chronic obstruction pulmonary disease , which might be a reflection of specific training effects in either oxidative or glycolytic muscle metabolic pathways . Further work is required to determine the role of the different exercise programmes and the particular category of patients for whom this might be beneficial We studied the impact of a 6-wk supervised , multimodality endurance exercise training program ( EXT ) on strength and endurance of ventilatory and peripheral muscles in patients with chronic airflow limitation ( CAL ) , and determined whether potential improvements contributed to relief of exertional breathlessness ( B ) and perceived leg effort/discomfort ( LE ) , respectively . Twenty breathless patients with stable CAL ( FEV1 = 41 + /- 3 % predicted ; mean + /- SEM ) were tested at 6-wk intervals at baseline , after a nonintervention control period ( pre-EXT ) , and post-EXT . Measurements included : pulmonary function tests ( PFTs ) , maximal inspiratory/expiratory pressures ( MIP , MEP ) , inspiratory muscle endurance ( V(LIM ) ) , quadriceps strength and endurance , exercise endurance , and submaximal cycle exercise with cardioventilatory and symptom responses . Measurements at baseline and pre-EXT were identical . Post-EXT , PFTs did not change ; exercise endurance measured on the treadmill , cycle ergometer , arm ergometer , and by 6-min walk distance increased 40 + /- 8 % , 43 + /- 10 % , 12 + /- 5 % , and 34 + /- 9 % , respectively ( p < 0.05 ) ; quadriceps strength increased 21 + /- 5 % ( p < 0.01 ) ; MIP and MEP increased 29 + /- 11 % and 27 + /- 11 % , respectively ( p < 0.05 ) ; V(LIM ) increased almost threefold ( p < 0.05 ) . At isotime near end-exercise , B , LE , carbon dioxide production ( VCO2 ) , oxygen consumption ( VO2 ) , ventilation , and breathing frequency ( F ) all fell after EXT ( p < 0.05 ) : deltaB correlated with deltaF ( r = 0.58 , p < 0.01 ) . Increased MIP and V(LIM ) did not correlate with improved breathlessness or exercise endurance . Similarly , changes in quadriceps strength and endurance did not correlate with changes in LE or exercise endurance . In conclusion , general nonspecific EXT improved ventilatory and peripheral muscle function in severe CAL , but such improvements did not appear to contribute significantly to reduced exertional symptoms and enhanced exercise performance In recent years quality of life instruments have been featured as primary outcomes in many r and omized trials . One of the challenges facing the investigator using such measures is determining the significance of any differences observed , and communicating that significance to clinicians who will be applying the trial results . We have developed an approach to elucidating the significance of changes in score in quality of life instruments by comparing them to global ratings of change . Using this approach we have established a plausible range within which the minimal clinical ly important difference ( MCID ) falls . In three studies in which instruments measuring  dyspnea , fatigue , and emotional function in patients with chronic heart and lung disease were applied the MCID was represented by mean change in score of approximately 0.5 per item , when responses were presented on a seven point Likert scale . Furthermore , we have established ranges for changes in question naire scores that correspond to moderate and large changes in the domains of interest . This information will be useful in interpreting question naire scores , both in individuals and in groups of patients participating in controlled trials , and in the planning of new trials QUESTIONS Does an eight-week program of walk training improve endurance walking capacity in people with COPD compared to cycle training ? Does walk training improve peak walking capacity , cycle capacity , and quality of life compared to cycle training ? Is the endurance shuttle walk test ( ESWT ) responsive to change in walking capacity elicited by exercise training ? DESIGN R and omised trial with concealed allocation , assessor blinding , and intention-to-treat analysis . PARTICIPANTS 36 people with stable COPD recruited with four dropouts . INTERVENTION Participants were r and omised into either a walk or cycle training group . Both groups trained indoors for 30 to 45 minutes per session , three times weekly over eight weeks at Concord Hospital . Training intensities were based on baseline peak exercise tests and progressed as able . OUTCOME MEASURES The primary outcome was endurance walking capacity measured by the ESWT . Secondary outcomes included peak walking capacity , peak and endurance cycle capacity , and health-related quality of life . Measures were taken at baseline ( Week 0 ) and following training ( Week 8) . RESULTS The walk training group increased their endurance walking time by 279 seconds ( 95 % CI 70 to 483 ) more than the cycle training group . No significant differences between the groups were found for any other outcome . CONCLUSION Ground walk training increased endurance walking capacity more than cycle training and was similar to cycle training in improving peak walking capacity , peak and endurance cycle capacity and quality of life . This study provides evidence for ground walking as a mode of exercise training in pulmonary rehabilitation programs We studied high intensity , symptom-limited , endurance exercise training in 52 patients with COPD participating in a pulmonary rehabilitation program . The patients had moderate to severe airway obstruction and reduced exercise tolerance with ventilatory limitation . The target workload for endurance exercise testing was 95 percent of the baseline maximum treadmill work load . At training weeks 1 , 4 and 8 , they were training at 85 , 84 , and 86 percent respectively , of baseline maximum . After rehabilitation , there was an increase in maximal treadmill work load , VO2max , and endurance exercise time , and a decrease in perceived symptoms . Patients who did not reach anaerobic threshold ( group 2 ) were able to train at a higher percentage of maximum exercise tolerance than patients who reached anaerobic threshold ( group 1 ) . The increase in exercise performance of both groups , however , was similar . We conclude that patients with moderate to severe COPD can perform exercise training successfully at intensity targets which represent higher percentages of maximum than typically recommended in normal individuals or other patients Our objective was to compare the effect of a 4−week homebased low and middle intensity and frequency training program in patients with moderate to severe chronic obstructive pulmonary disease . From 124 patients hospitalized with chronic obstructive lung disease ( COPD ) in an 18-month period 65 fulfilled the inclusion criteria and were invited to participate . Only 31 ( 48 % ) accepted and among these only 20 patients ( 31 % of invited ) completed the 4-week study period . The walking time in seconds in a st and ardized treadmill walking test was unchanged after 4 weeks of low intensity training 60 minutes per week for two weekly training sessions . In contrast , the walking time in seconds increased 55 % ( p < 0.001 ) from 321 seconds to 499 seconds in 9 patients who completed 4 weeks of middle intensity training which comprised 21/2 hours of training per week for 5 weekly training sessions . There was no change in lung function over the 4 weeks but the combined score for physical quality of life ( physical component summary ) measured by SF-36 increased ( p < 0.05 ) with both low intensity and middle intensity physical training . In conclusion , homebased physical training , which aims at improvements in patient performance and quality of life as part of pulmonary rehabilitation programs , is only accepted by about one-third of unselected patients with moderate to severe COPD . The minimum training time necessary to improve physical performance is 2–3 hours per week of middle intensity training AIM In this study , the effects of a 12-week hospital-based outpatient pulmonary rehabilitation program ( HRP ) are compared with those of a 12-week home-care rehabilitation program ( HCRP ) in COPD patients . A control group received no rehabilitation therapy . METHODS After r and omization and stratification , effects on lung function , exercise performance ( 4-min walking test and cycle ergometer test ) , dyspnea , and leg effort during exercise , and well-being were assessed in 45 COPD patients with moderate to severe airflow limitation ( mean [ SD ] FEV1 percent predicted , 42.8 [ 8.4 ] ) . RESULTS After HRP and HCRP , at 3 to 6 months after the start of the study , equal improvements were detected in exercise capacity and in Borg dyspnea and leg effort scores at similar work levels during the cycle test . However , whereas after HRP at longer term values tended to return to baseline outcome , after HCRP a further ongoing significant improvement in exercise capacity was observed , while Borg dyspnea scores remained significantly improved over 18 months . Improvements in cycle workload and dyspnea score were significantly better maintained after HCRP as compared with HRP . Lung function , arterial oxygen saturation , and heart frequency during exercise did not change . A significant improvement in well-being was maintained over 18 months in both rehabilitation groups . CONCLUSION Beneficial effects are achieved both after a HRP and a HCRP in COPD patients with moderate to severe airflow limitation . Yet we recommend to initiate HCRPs as improvements are maintained longer and are even further strengthened in this setting 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 
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Consequently , there are insufficient data to draw any conclusions on exercise capacity , symptoms and HRQoL for this comparison .
For comparisons between continuous and interval training , both appear to be equally effective in improving exercise capacity , symptoms and