***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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    ***EXAMPLES*** 
    Input: This study was design ed to evaluate the performance of movement detectors ( pedometers ) in measuring daily activity of patients with chronic lung disease . Three groups of subjects were studied : group 1 : 25 patients with stable nonhypercapnic chronic obstructive pulmonary disease ( COPD ) ( forced expiratory volume in one second ( FEV1 ) = 47+/-9 % predicted ) studied twice , one month apart ; group 2 : 25 patients with chronic respiratory failure studied before and three months after nasal nocturnal mechanical ventilation ; and group 3 : 25 normal healthy subjects studied once . The median level of activity in the healthy subjects ( group 3 ) was three times greater than in either group of patients ( groups 1 and 2 ) . Activity levels were not correlated with age , sex or employment status . The repeatability of the activity counts in the nonhypercapnic COPD patients was high ( intraclass correlation coefficient=0.94 ) and in these patients activity correlated significantly with FEV1 ( r=0.54 , p=0.006 ) . In the respiratory failure patients , daytime arterial carbon dioxide pressure ( Pa , CO2 ) improved following nasal nocturnal mechanical ventilation ( NMV ) ( pre NMV : 8.5+/-1.2 kPa ; post NMV : 6.2+/-0.5 kPa ) , health status improved ( p<0.004 ) and daily movement count doubled ( p<0.0001 ) . This increase correlated with change in Pa , CO2 ( r-0.53 , p=0.006 ) , but not with improved health status . We conclude that motion detectors may provide repeatable measures of daily activity that are related to physiological impairment and improvement following treatment . Activity counts appear to be complementary to estimates of exercise limitation obtained using health question naires Study objectives The aims of this study were to establish whether pulmonary rehabilitation ( PR ) improves domestic function and daily activity levels in COPD and whether individually targeted exercise is more effective than general exercise . Design Prospect i ve r and omized , controlled trial . Setting Outpatient PR program in secondary care . Participants One-hundred eighty patients ( mean [ ±SD ] age , 68.3 ± 8.6 years ; FEV 1 , 0.95 ± 0.4 L ; FEV 1 /FVC ratio , 0.51 ± 0.15 ; 111 male patients ; 69 female patients ) with stable COPD . One hundred twenty-one patients completed the study . Interventions Patients were r and omized to a conventional 7-week general exercise program ( [ GEP ] n=90 ) or an individually targeted exercise program ( [ ITEP ] n=90 ) . Measurement and results Daily activity was measured using ambulatory activity monitors ( Z80 –32k V1 Int ; Gaehwiler Electronics ; Hombrechtikon , Switzerl and ) . These were lightweight devices , which contained a uniaxial accelerometer . Domestic function was assessed by the Canadian Occupational Performance Measure ( COPM ) . Exercise performance was assessed by the incremental shuttle walk test ( ISWT ) and the endurance shuttle walk test and health status by the chronic respiratory question naire – self-reported . Activity monitor counts increased by 29.18 % ( 95 % confidence interval [ CI ] , 3.19 to 55.17 ; p=0.03 ) for the GEP and 40.63 % ( 95 % CI , 7.42 to 73.83 ; p=0.02 ) for the ITEP . Mean COPM performance scores increased by 1.71 ( 95 % CI , 1.37 to 2.05 ; p=0.0001 ) for the GEP and 1.46 ( 95 % CI , 1.05 to 1.87 ; p=0.0001 ) for the ITEP . Mean COPM satisfaction scores increased by 2.27 ( 95 % CI , 1.74 to 2.81 ; p=0.0001 ) for the GEP and 2.04 ( 95 % CI , 1.56 to 2.52 ; p=0.0001 ) for the ITEP . ISWT scores increased by 81.72 m ( range , 63.83 to 99.62 ) for the GEP and by 85.52 m ( range , 67.62 to 103.42 ) for the ITEP . No statistically significant difference was found between the general exercise group and the individually targeted exercise group for any outcome measure . Conclusions Pulmonary rehabilitation improves domestic function and physical activity . This study also demonstrates that general exercise training is as effective as individually targeted training Chronic obstructive pulmonary disease ( COPD ) is a highly prevalent disease . Currently , severity Global initiative for chronic Obstructive Lung Disease ( GOLD ) criteria are used to diagnose the severity of COPD , but a new grading system , the body mass index , bronchial obstruction , dyspnea , exercise ( BODE ) index , was recently proposed to provide useful prognostic information . The objective of this study is to evaluate the association between health-related quality of life ( HRQOL ) and COPD severity assessed by two criteria : the GOLD classification and the BODE index . Sixty-four patients with COPD were examined with lung function tests and specific and generic HRQOL question naires ( St. George 's Respiratory Question naire [ SGRQ ] , Nottingham Health Profile [ NHP ] ) . Participants were divided into four severity groups using the GOLD guidelines and the BODE index quartiles . The association between NHP and SGRQ subscales , and the BODE index was significant ( P < 0.01 ) . However , the GOLD classification shows a correlation only with SGRQ total score ( P < 0.05 ) but not with NHP or SGRQ subscales . There was an association of the SGRQ total score between the severity groups of BODE ( P = 0.0001 ) , but there was no difference in the SGRQ total score between the severity groups of GOLD classification ( P = 0.244 ) . The present study suggests that COPD severity assessed by the BODE index can be more directly related with HRQOL OBJECTIVE To study the effects of a lifestyle physical activity counseling program with feedback of a pedometer during pulmonary rehabilitation . METHODS Twenty-one chronic obstructive pulmonary disease ( COPD ) patients were r and omized to an experimental group that followed a regular rehabilitation program plus the counseling intervention or to a control group that only followed rehabilitation . The primary outcome was daily physical activity assessed by pedometers . Secondary outcomes were physical fitness , health-related quality of life , activities of daily living , depression and self-efficacy . RESULTS The experimental group showed an increase of 1,430 steps/day ( + 69 % from baseline ) , whereas the control group showed an increase of 455 steps/day ( + 19 % ) ( p = 0.11 for group x time interaction ) . The secondary outcomes showed no differences . CONCLUSION AND PRACTICE IMPLICATION S This study showed that the use of the pedometer , in combination with exercise counseling and the stimulation of lifestyle physical activity , is a feasible addition to pulmonary rehabilitation which may improve outcome and maintenance of rehabilitation results A sample of 37 patients with severe chronic obstructive pulmonary disease ( COPD ) drawn from a larger group of 64 patients being studied in a r and omized trial of nebulizer versus high-dose inhaler therapy , and similar in age and gender mix , was interviewed in depth , with a view to illuminating st and ardized outcome measures and improving the underst and ing of these patients ' needs . Three patients are described in detail . The interview material was analysed using non-computerized methods . Quality of life was seen as depending mainly on family relationships , opportunities afforded locally for neighbourliness and freedom from fear , mobility and independence in the activities of daily living , and the absence or successful mitigation of symptoms of concomitant disease . Disease-specific , symptom-oriented outcome measures may miss these . Additionally , the near and repeatedly threatening approach of death recommended extension of a palliative approach to endstage COPD RATIONALE We have previously reported that regular physical activity reduces risk of chronic obstructive pulmonary disease ( COPD ) exacerbation .  We hypothesized that higher levels of regular physical activity could reduce the risk of COPD by modifying smoking-related lung function decline . OBJECTIVE To estimate the longitudinal association between regular physical activity and FEV(1 ) and FVC decline and COPD risk . METHODS A population -based sample ( n = 6,790 ) was recruited and assessed with respect to physical activity , smoking , lung function , and other covariates , in Copenhagen in 1981 - 1983 , and followed until 1991 - 1994 . Mean level of  physical activity  between baseline and follow-up was classified into " low , " " moderate , " and " high . " FEV(1 ) and FVC decline rates were expressed as milliliters per year . COPD was defined as FEV(1)/FVC < or = 70 % . Adjusted associations between physical activity and FEV(1 ) and FVC decline , and COPD incidence , were obtained using linear and logistic regression , respectively . RESULTS Active smokers with moderate and high physical activity had a reduced FEV(1 ) and FVC decline compared with those with low physical activity ( relative change of + 2.6 and + 4.8 ml/yr of FEV(1 ) , P-for-trend = 0.006 , and + 2.6 and + 7.7 ml/yr of FVC , P-for-trend < 0.0001 , for the moderate and high physical activity group , respectively ) , after adjusting for all potential confounders and risk factors of lung function decline . Active smokers with moderate to high physical activity had a reduced risk of developing COPD as compared with the low physical activity group ( odds ratio , 0.77 ; p = 0.027 ) . CONCLUSIONS This prospect i ve study shows that moderate to high levels of regular physical activity are associated with reduced lung function decline and COPD risk among smokers The effect of endurance training on muscle electrical activity during general exercise testing was investigated in physically active patients with chronic obstructive pulmonary disease ( COPD ) . Before and after rehabilitation , patients performed identical incremental exercise tests . Pulmonary gas exchange , venous lactate and pyruvate concentrations , and the quadriceps electromyographic signal were sample d every minute throughout exercise testing . Three weeks of rehabilitation increased exercise capacity without modifying pulmonary function . M-wave amplitude , root mean square ( RMS ) of electromyographic activity , and RMS/oxygen uptake were increased significantly during post-rehabilitation testing at the same exercise intensity compared to pre-rehabilitation . Median frequency was significantly lower after training . These modifications reflect greater muscle excitability , greater muscle activation for the same level of exercise , and higher recruitment of slow-twitch fibers . Pulmonary rehabilitation in active COPD patients may normalize the electrical activity of skeletal muscles during incremental dynamic exercise . The electromyographic signal confirms neuromuscular changes after endurance training OBJECTIVE To investigate whether a 12-week pedometer-based exercise counseling strategy is feasible and effectively enhances daily physical activity in outclinic Chronic Obstructive Pulmonary Disease ( COPD ) patients who do not participate in a rehabilitation program in a controlled way . METHODS 35 outclinic COPD patients ( 21 males , mean age 62 years , GOLD I-III , mean FEV(1)% predicted 64.7 ) were r and omized for a 12-week individual pedometer-based exercise counseling program promoting daily physical activities or usual care .  Daily physical activity ( DigiWalker SW-200 ) , physical fitness , health-related quality of life , self-efficacy , fatigue , depression and motivation to be physically active were assessed before and after the intervention . RESULTS After the intervention , COPD patients in the exercise counseling group showed a significant increase in their mean number of steps/day ( from 7087 to 7872 ) , whereas the usual care group showed a decrease ( from 7539 to 6172 ) . Significant differences favoring the exercise counseling group were demonstrated in arm strength , leg strength , health-related quality of life and intrinsic motivation to be physically active . CONCLUSION Our study shows that a 12-week pedometer-based exercise counseling strategy is feasible and effectively enhances daily physical activity , physical fitness , health-related quality of life and intrinsic motivation in outclinic COPD patients who do not participate in a rehabilitation program . PRACTICE IMPLICATION S The feasibility of our exercise counseling strategy is good and patients were motivated to participate BACKGROUND Despite a variety of benefits brought by pulmonary rehabilitation to patients with COPD , it is unclear whether these patients are more active during daily life after the program . METHODS Physical activities in daily life ( activity monitoring ) , pulmonary function ( spirometry ) , exercise capacity ( incremental cycle-ergometer testing and 6-min walk distance testing ) , muscle force ( quadriceps and h and grip force , and inspiratory and expiratory maximal pressures ) , quality of life ( chronic respiratory disease question naire ) , and functional status ( pulmonary functional status and dyspnea question naire-modified version ) were assessed at baseline , after 3 months of a multidisciplinary rehabilitation program , and at the end of a 6-month multidisciplinary rehabilitation program in 29 patients ( mean [ + /- SD ] age , 67 + /- 8 years ; FEV(1 ) , 46 + /- 16 % predicted ) . RESULTS Exercise capacity , muscle force , quality of 
    Output:
    
Reduced daily physical activity is associated with higher levels of airway obstruction , higher levels of systemic inflammation , and lower levels of physical fitness .
In conclusion , this is the first review that examined the level , type and determinants of daily physical activity in COPD .
It demonstrates that reduced daily physical activity frequently occurs in COPD patients , yet with a large variation .