***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: Long-term treatment of chronic bronchitis with chest physiotherapy with or without positive expiratory pressure ( PEP ) by mask was studied in 43 patients r and omly allocated to PEP treatment ( PEP group , 20 patients ) and conventional chest physiotherapy ( control group , 23 patients ) . After instruction , the treatments were self-administered twice daily for 12 months ( 34 patients ) and 5 months ( 9 patients ) . Twice weekly , patients filled in a diary concerning symptoms . The PEP group had significantly less cough and less mucus production . The number of acute exacerbations were calculated from the diaries and were lower in the PEP group compared to the control group , and 85 percent of the patients in the PEP group were free from acute exacerbations versus 48 percent in the control group . The PEP group also used less antibiotics and mucolytics . The PEP group had a small increase in FEV1 of mean 62 ml compared to a small decrease of 43 ml for the control group . Treatment with a simple PEP device can reduce morbidity in patients with chronic bronchitis and may preserve lung function from a more rapid decline BACKGROUND Supplemental oxygen in patients with chronic obstructive pulmonary disease ( COPD ) and exercise hypoxaemia improves exercise capacity and dyspnoea . However , the benefit of oxygen during pulmonary rehabilitation in these patients is still unknown . METHODS Twenty five patients with stable COPD ( mean ( SD ) forced expiratory volume in one second ( FEV1 ) 0.76 ( 0.29 ) l and 30.0 (9.89)% predicted , arterial oxygen tension ( Pao 2 ) 8.46 ( 1.22 ) kPa , arterial carbon dioxide tension ( Paco 2 ) 6.32 ( 1.01 ) kPa ) and significant arterial desaturation on exercise ( 82.0 (10.4)% ) were entered onto a pulmonary rehabilitation programme . Patients were r and omised to train whilst breathing oxygen ( OT ) ( n = 13 ) or air ( AT ) ( n = 12 ) , both at 4 l/min . Assessment s included exercise tolerance and associated dyspnoea using the shuttle walk test ( SWT ) and Borg dyspnoea score , health status , mood state , and performance during daily activities . RESULTS The OT group showed a significant reduction in dyspnoea after rehabilitation compared with the AT group ( Borg mean difference –1.46 ( 95 % CI –2.72 to –0.19 ) ) but there were no differences in other outcome measures : SWT difference –23.6 m ( 95 % CI –70.7 to 23.5 ) , Chronic Respiratory Disease Question naire 3.67 ( 95 % CI –7.70 to 15.1 ) , Hospital Anxiety and Depression Scale 1.73 ( 95 % CI –2.32 to 5.78 ) , and London Chest Activity of Daily Living Scale –2.18 ( 95 % CI –7.15 to 2.79 ) . At baseline oxygen significantly improved SWT ( mean difference 27.3 m ( 95 % CI 14.7 to 39.8 ) and dyspnoea ( –0.68 ( 95 % CI –1.05 to –0.31 ) ) compared with placebo air . CONCLUSIONS This study suggests that supplemental oxygen during training does little to enhance exercise tolerance although there is a small benefit in terms of dyspnoea . Patients with severe disabling dyspnoea may find symptomatic relief with supplemental oxygen 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 Pulmonary rehabilitation is beneficial for patients with chronic lung disease . However , long-term maintenance has been difficult to achieve after short-term treatment . We evaluated a telephone-based maintenance program after pulmonary rehabilitation in 172 patients with chronic lung disease recruited from pulmonary rehabilitation graduates . Subjects were r and omly assigned to a 12-month maintenance intervention with weekly telephone contacts and monthly supervised reinforcement sessions ( n = 87 ) or st and ard care ( n = 85 ) and followed for 24 months . Except for a slight imbalance between sexes , experimental and control groups were equivalent at baseline and showed similar improvements after rehabilitation . During the 12-month intervention , exercise tolerance ( maximum treadmill workload and 6-minute walk distance ) and overall health status ratings were better maintained in the experimental group together with a reduction in hospital days . There were no group differences for other measures of pulmonary function , dyspnea , self-efficacy , generic and disease-specific quality of life , and health care use . By 24 months , there were no significant group differences . Patients returned to levels close to but above prerehabilitation measures . We conclude that a maintenance program of weekly telephone calls and monthly supervised sessions produced only modest improvements in the maintenance of benefits after pulmonary rehabilitation The purpose of this study was to test the effectiveness of a taped relaxation message in reducing dyspnea and anxiety in chronic obstructive pulmonary disease ( COPD ) patients . Twenty-six adult COPD patients with dyspnea were r and omly assigned to two groups . The treatment group was taught relaxation using a prerecorded tape while the control group was instructed to sit quietly .  Skin temperature , heart rate , and respiratory rate were recorded for all subjects during a total of four weekly sessions . Anxiety , dyspnea , and airway obstruction were measured at the beginning and end of the study . The relaxation group achieved the preset relaxation criteria . Dyspnea , anxiety , and airway obstruction were induced in the relaxation group while the control group remained the same or became worse 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 On theoretical grounds it is assumed that positive expiratory pressure mask physiotherapy ( PEP ) as a means of promoting mucus clearance is especially effective in the more distal airways . In a r and omized cross-over trial including a control measurement the effect of PEP and of the forced expiration technique combined with postural drainage ( FET/PD ) on regional lung clearance was evaluated in seven patients with chronic bronchitis and abundant sputum production ( mean 32 g.day-1 ) .  PEP consisted of positive expiratory pressure mask breathing interspersed with breathing exercises , forced expiration manoeuvres ( huffing ) and , if necessary , coughing . FET consisted of breathing exercises , huffing and also , if necessary , coughing . FET was combined with PD . Following inhalation of a radio-aerosol  regional lung clearance was estimated by means of gamma camera imaging . The results after PEP appeared to be not significantly different from control . The mean clearance in all three lung zones ( peripheral , intermediate and inner ) was largest after FET/PD as compared with PEP and control . Statistical significance ( p less than 0.02 ) was reached only for clearance in the inner region . It is concluded that PEP has no demonstrable effect on regional lung clearance in these patients Supplemental oxygen improves exercise tolerance of normoxemic and hypoxemic chronic obstructive pulmonary disease ( COPD ) patients . We determined whether nonhypoxemic COPD patients undergoing exercise training while breathing supplemental oxygen  achieve higher intensity and therefore improve exercise capacity more than patients breathing air . A double-blinded trial was performed involving 29 nonhypoxemic patients ( 67 years , exercise SaO2 > 88 % ) with COPD ( FEV1 = 36 % predicted ) . All exercised on cycle ergometers for 45 minutes , 3 times per week for 7 weeks at high-intensity targets . During exercise , they received oxygen ( 3 L/minute ) ( n = 14 ) or compressed air ( 3 L/minute ) ( n = 15 ) . Both groups had a higher exercise tolerance after training and when breathing oxygen . However , the oxygen-trained group increased the training work rate more rapidly than the air-trained group . The mean + /- SD work rate during the last week was 62 + /- 19 W ( oxygen-trained group ) and 52 + /- 22 W ( air-trained group ) ( p < 0.01 ) . After training , endurance in constant work rate tests increased more in the oxygen-trained group ( 14.5 minutes ) than in the air-trained group ( 10.5 minutes ) ( p < 0.05 ) . At isotime , the breathing rate decreased four breaths per minute in the oxygen-trained group and one breath per minute in the air-trained group ( p = 0.001 ) . We conclude that supplemental oxygen provided during high-intensity training yields higher training intensity and evidence of gains in exercise tolerance in laboratory testing 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 
    Output:
    
Conclusions : Strong recommendations support the use of physical exercise training to improve health-related quality of life and functional exercise capacity .