Physical Activity and Sedentary Behavior as Treatable Traits for Clinical Control in Moderate-to-Severe Asthma.

BACKGROUND: Physical activity and sedentary behavior are treatable traits that may impact asthma control in distinct manners, but this impact remains poorly understood. OBJECTIVE: To evaluate the influence of physical activity and sedentary behavior on clinical control in adults with moderate-to-severe asthma. METHODS: This cross-sectional, multicentric study included 426 individuals with moderate-to-severe asthma. Assessments included physical activity and sedentary time (actigraphy), clinical asthma control (Asthma Control Questionnaire [ACQ]), quality of life (Asthma Quality of Life Questionnaire), anxiety and depression symptoms (Hospital Anxiety and Depression Scale), anthropometric data, and lung function. Participants were grouped according to physical activity levels and sedentary behavior. RESULTS: Participants who walked ≥7500 steps/day presented better ACQ scores than those who walked <7500 steps/day (P < .05), independent of sedentary status. The percentage of patients with controlled asthma was higher in the active/sedentary (43.9%) and active/nonsedentary (43.8%) groups than in the inactive/sedentary (25.4%) and inactive/nonsedentary (23.9%) groups (P < .02). The likelihood of having uncontrolled asthma according to the treatable traits of physical inactivity (odds ratio [95% confidence interval]: 2.36 [1.55-3.59]), higher anxiety (2.26 [1.49-3.42]), and depression symptoms (1.95 [1.28-2.95]) was significant (P ≤ .002). Obesity and sedentary time were not associated with asthma control. CONCLUSIONS: Our results show that ≥7500 steps/day is associated with better asthma control independent of sedentary time in adults with moderate-to-severe asthma. Physical inactivity, anxiety, and depression symptoms are associated with higher odds of uncontrolled asthma. These results suggest that interventions should mainly focus on increasing physical activity rather than reducing sedentary time.

Core Function in Adults With Severe Asthma and Its Relationship With Breathing Symptoms.

BACKGROUND: People with asthma may have skeletal muscle dysfunction but data describing core function in severe asthma are limited. OBJECTIVE: To compare core function between people with severe asthma and healthy controls and to determine the difference between males and females. Furthermore, we aimed to investigate the association between core function and breathing symptoms. METHOD: Adults with a diagnosis of severe asthma and healthy controls undertook an assessment that included 3 core function tests: partial sit-up, Biering-Sorensen, and side bridge. Breathing symptoms were assessed by the modified Medical Research Council dyspnea scale, modified Borg scale, and Nijmegen questionnaire. RESULTS: People with severe asthma (n = 136) (38% male, age median [Q1-Q3] 59 y [45-68], body mass index 30 kg/m2 [26-37]) were compared with 66 people without respiratory disease (47% male, age 55 y [34-65], body mass index 25 kg/m2 [22-28]). There was no difference between groups in the partial sit-up (P = .09). However, participants with severe asthma performed worse with the Biering-Sorensen (P < .001), and the left and right side bridge test (P < .001 for both) than the healthy comparison group. Similar results were found when comparing males and females separately. Males with severe asthma had increased function compared with their female counterparts in the left side bridge test. Core function tests correlated with the breathing symptom measures, the modified Medical Research Council, modified Borg scale, and Nijmegen questionnaire (-0.51 > r > -0.19; P ≤ .03). CONCLUSIONS: Adults with severe asthma have worse core function than their control counterparts, independent of sex. Furthermore, as core function decreases, breathing symptoms increase.

Physical activity and inactivity among different body composition phenotypes in individuals with moderate to very severe chronic obstructive pulmonary disease.

BACKGROUND: The phenotype profiling of individuals with chronic obstructive pulmonary disease (COPD) according to impairments in body composition and level of physical activity in daily life (PADL) needs to be determined. OBJECTIVE: To verify if individuals with COPD classified as physically active/inactive present different characteristics within different body composition phenotypes. METHODS: Individuals with COPD were cross-sectionally stratified into four groups according to fat-free and fat mass indexes: Normal Body Composition (NBC), Obese (Ob), Sarcopenic (Sarc), and Sarcopenic/Obese (Sarc/Ob). Additionally, individuals had their PADL level objectively assessed through activity monitoring during two weekdays for at least 10h/day, and then were classified as physically active (Act) or inactive (Inact) according to international recommendations. Lung function (spirometry), exercise capacity (6-minute walking test [6MWT]) and peripheral muscle strength (1-repetition maximum [1RM]) were also assessed. RESULTS: 176 individuals with COPD (mean±standard deviation age: 67±8 years, body mass index 26±6kg/m2, FEV1 47±16%predicted) were classified as: NBC+Act (17%), NBC+Inact (22%), Ob+Act (6%), Ob+Inact (10%), Sarc+Act (12%), Sarc+Inact (9%), Sarc/Ob+Act (8%) and Sarc/Ob+Inact (16%). The Sarc/Ob+Inact group presented lower 6MWT and 1RM for knee extension compared to NBC+Act, NBC+Inact, and Ob+Act groups (p<0.05). The Sarc/Ob+Inact group also presented lower FEV1% predicted, 1RM for elbow flexion and elbow extension compared to the NBC+Act and NBC+Inact groups and lower 1RM for elbow extension compared to Ob+Inact group (p<0.05). CONCLUSION: The combination of sarcopenia, obesity, and physical inactivity was shown to be detrimental in individuals with COPD. Therefore, this profile is a main therapeutic target for improving PADL level and/or body composition.

Profile and determinants of daily physical activity objectively assessed in university students.

BACKGROUND: The aim of this study was to quantify and compare physical activity (PA) levels of university students from different fields of study, and to investigate its correlates. METHODS: 221 students (111 female, 20 [18-23] years), from different study fields were cross-sectionally assessed for daily PA (pedometer), cardiorespiratory fitness (20 m Shuttle Run Test-20mSRT), health-related quality of life (HRQoL), anxiety and depression symptoms. RESULTS: In general, 60% of the students were physically active (>8000 steps/day), presented good HRQoL and cardiorespiratory fitness, minimal symptoms of depression and moderate of anxiety. The highest PA level was observed in students from physical education and sport sciences, and the lowest in those from social sciences (median [IQR]: 9882 [8435-13510] versus 7593 [6070-9753] steps/day, respectively; P<0.01). Male students were more active than female. Steps/day was moderately associated with VO2max (r=0.42), VO2%pred (r=0.41) and distance achieved in the 20mSRT (r=0.43) (P<0.0001 for all), and weakly associated with anxiety symptoms (r=-0.20; P=0.004) and HRQoL domains (0.15

Clinical impact of body composition phenotypes in patients with COPD: a retrospective analysis.

BACKGROUND/OBJECTIVES: Abnormal body composition is an independent determinant of COPD outcomes. To date, it is already known that patient stratification into body composition phenotypes are associated with important outcomes, such as exercise capacity and inflammation, but there are no data comparing physical activity and muscle strength among these phenotypes. Thus, the aim of this study was to compare clinical characteristics and physical function in patients with COPD stratified into body composition phenotypes. SUBJECTS/METHODS: Two-hundred and seventy stable COPD patients were classified according to the 10th and 90th percentiles of sex-age-BMI-specific reference values for fat-free and fat mass indexes into four groups: Normal body composition (NBC), Obese, Sarcopenic, and Sarcopenic-obese (SO). Patients underwent assessment of exercise capacity, peripheral and respiratory muscle strength, physical activity, dyspnea severity, functional status, and symptoms of anxiety and depression. RESULTS: The prevalence of patients classified as NBC, Obese, Sarcopenic, and SO was 39%, 13%, 21%, or 27%, respectively. SO presented lower 6MWT compared with NBC (P < 0.05). Sarcopenic and SO groups presented worse muscle strength compared with NBC (P < 0.05). Sarcopenic group presented more time in moderate-to-vigorous physical activity compared to all other groups (P < 0.05) and less sedentary time when compared with NBC and obese groups (P < 0.05). There were no differences regarding dyspnea severity, functional status, and symptoms of anxiety and depression (P > 0.16). Sarcopenic and SO groups had, respectively, 7.8 [95% CI: 1.6-37.7] and 9.5 [2.2-41.7] times higher odds to have a 6MWT equal or lower to 350 meters. CONCLUSIONS: Body composition phenotypes are associated with physical function in patients with COPD. Sarcopenic-obese patients were the most impaired.

Difference Between Slow and Forced Vital Capacity and Its Relationship with Dynamic Hyperinflation in Patients with Chronic Obstructive Pulmonary Disease.

The aim of the study was to investigate the relationship between slow and forced vital capacity (SVC-FVC) difference with dynamic lung hyperinflation (DH) during the 6-min walking test (6MWT) in subjects with chronic obstructive pulmonary disease (COPD). Twenty-four subjects with COPD (12 males; 67 ± 6 years; forced expiratory volume in first second [FEV1] 56 ± 18% predicted) performed lung function tests by spirometry and plethysmography. DH was assessed by serial measurements of inspiratory capacity (IC) performed during the 6MWT and defined as ∆IC ≥ 150 mL or 10%. IC decrease significantly during the 6MWT (ΔCI: - 0.48 ± - 0.40 L; P < 0.0001), and 18 individuals (75%) presented DH. There was significant difference when comparing IC measured at rest with the other serial IC measurements (P < 0.0001). Correlation between the SVC-FVC difference and DH during the 6MWT was r = - 0.38; P = 0.06. The SVC-FVC difference presented only weak correlation with the development of DH during the 6MWT in patients with COPD.

Heart Rate Recovery, Physical Activity Level, and Functional Status in Subjects With COPD.

BACKGROUND: A normal heart rate reflects the balance between the sympathetic and parasympathetic autonomic nervous system. When the difference between heart rate at the end of an exercise test and after 1 min of recovery, known as the 1-min heart rate recovery, is ≤ 12 beats/min, this may indicate an abnormal delay. We sought to compare physical activity patterns and subjects' functional status with COPD with or without delayed 1-min heart rate recovery after the 6-min walk test (6MWT). METHODS: 145 subjects with COPD (78 men, median [interquartile range (IQR)] age 65 [60-73] y, body mass index 25 [21-30] kg/m2, FEV1 45 ± 15% predicted) were underwent the following assessments: spirometry, 6MWT, functional status, and physical activity in daily life (PADL). A delayed heart rate recovery of 1 min was defined as ≤ 12 beats/min. RESULTS: Subjects with delayed 1-min heart rate recovery walked a shorter distance in the 6MWT compared to subjects without delayed heart rate recovery (median [IQR] 435 [390-507] m vs 477 [425-515] m, P = .01; 81 [71-87] vs 87 [79-98]% predicted, P = .002). Regarding PADL, subjects with delayed heart rate recovery spent less time in the standing position (mean ± SD 185 ± 89 min vs 250 ± 107 min, P = .002) and more time in sedentary positions (472 ± 110 min vs 394 ± 129 min, P = .002). Scores based on the self-care domain of the London Chest Activity of Daily Living questionnaire and the activity domain of the Pulmonary Functional Status and Dyspnea questionnaire were also worse in the group with delayed heart rate recovery (6 ± 2 points vs 5 ± 2 points; P = .039 and 29 ± 24 points vs 19 ± 17 points; P = .037, respectively). CONCLUSIONS: Individuals with COPD who exhibit delayed 1-min heart rate recovery after the 6MWT exhibited worse exercise capacity as well as a more pronounced sedentary lifestyle and worse functional status than those without delayed heart rate recovery. Despite its assessment simplicity, heart rate recovery after the 6MWT can be further explored as a promising outcome in COPD.

Oxygen Desaturation in Daily Life and During a Laboratory-Based Protocol of Activities of Daily Living in COPD: Is There Relationship?

PURPOSE: To analyze the relationship between oxygen desaturation episodes during a laboratory-based ADL protocol and in real-life routine in patients with stable chronic obstructive pulmonary disease (COPD). METHODS: Twenty patients with stable COPD (12 men, 70 ± 7 years, FEV1% 54 ± 15 predicted) with no indication for long-term oxygen therapy (LTOT) were submitted to assessments including ADL performance by the Londrina ADL Protocol (LAP) and level of physical activity in daily life, both while submitted to simultaneous activity and pulse oximeter monitoring. RESULTS: Episodes of desaturation ≥ 4% (ED ≥ 4%) during the LAP were correlated both with ED ≥ 4% in daily life (r = 0.45) and number of episodes of SpO2 under 88% (ED < 88%) in daily life (r = 0.59). ED < 88% during the LAP was also correlated with ED < 88% in daily life (r = 0.51), explaining 43% of its variance. CONCLUSION: In stable patients with COPD and no indication of LTOT, episodes of desaturation during a lab-based ADL protocol are moderately related to episodes of desaturation in daily (real) life, especially those episodes under 88%.

Sedentary Behaviour and Physical Inactivity in Patients with Chronic Obstructive Pulmonary Disease: Two Sides of the Same Coin?

Despite the growing interest in sedentarism, there is no available information on the profile of patients with COPD according to sedentary behaviour (SB) and with a detailed analysis of minute-by-minute bouts. Hence, the aims of this study were to quantify the time spent in SB, light activities and moderate-to-vigorous physical activities (MVPA) and to verify the relationship of MVPA and SB in individuals with COPD, as well as to identify the profile of those physically (in)active and (non)-sedentary. A cross-sectional study in which physical activity in daily life was objectively assessed through the use of SenseWear Pro 2 Armband (BodyMedia) during 2 consecutive weekdays, 12 h/day. Analysis was performed minute-by-minute for each day of each patient. MVPA comprised time spent >3 metabolic equivalents (MET), whereas light activities corresponded to time spent between 1.5 and 3 MET and SB to time spent <1.5 MET. A total of 137 subjects with COPD (66 ± 8years; FEV1 46 [31-57] %pred; BMI 26 [22-30] kg/m2) were analysed. Time spent in MVPA and SB presented strong negative correlation (r = -0.72, P < 0.001). Minute-by-minute analysis showed that patients with COPD spend most of their time in SB. SB accounted for 40% of all bouts >1 minute, whereas only 14% these bouts concern MVPA. Patients combining two positive characteristics (physically active and non-sedentary) have better clinical profile than others. In conclusion, SB is negatively correlated with MVPA in patients with COPD. Furthermore, patients classified as physically active (i.e., those who reach MVPA recommendations) in combination with a non-sedentary lifestyle present markedly better clinical conditions.

Physical activity patterns and clusters in 1001 patients with COPD.

We described physical activity measures and hourly patterns in patients with chronic obstructive pulmonary disease (COPD) after stratification for generic and COPD-specific characteristics and, based on multiple physical activity measures, we identified clusters of patients. In total, 1001 patients with COPD (65% men; age, 67 years; forced expiratory volume in the first second [FEV1], 49% predicted) were studied cross-sectionally. Demographics, anthropometrics, lung function and clinical data were assessed. Daily physical activity measures and hourly patterns were analysed based on data from a multisensor armband. Principal component analysis (PCA) and cluster analysis were applied to physical activity measures to identify clusters. Age, body mass index (BMI), dyspnoea grade and ADO index (including age, dyspnoea and airflow obstruction) were associated with physical activity measures and hourly patterns. Five clusters were identified based on three PCA components, which accounted for 60% of variance of the data. Importantly, couch potatoes (i.e. the most inactive cluster) were characterised by higher BMI, lower FEV1, worse dyspnoea and higher ADO index compared to other clusters ( p < 0.05 for all). Daily physical activity measures and hourly patterns are heterogeneous in COPD. Clusters of patients were identified solely based on physical activity data. These findings may be useful to develop interventions aiming to promote physical activity in COPD.

Sedentary Behavior Is an Independent Predictor of Mortality in Subjects With COPD.

BACKGROUND: The terms sedentary behavior and physical inactivity have been confusingly mixed. Although the association between physical inactivity and mortality has been shown previously in subjects with COPD, this association had not yet been investigated with regard to sedentarism. The aim of this work was to investigate the impact of sedentary behavior on mortality of subjects with COPD and to propose a cutoff point of sedentarism with prognostic value. METHODS: In this retrospective cohort study, sedentary behavior was assessed with 2 activity monitors (DynaPort and Sensewear armband) in 101 subjects with COPD from 2006 to 2011. Vital status was then ascertained in 2015. The following 6 variables of sedentary behavior were analyzed: average of metabolic equivalent of task (MET)/d (reflecting intensity); time spent/d lying, sitting, and lying + sitting (reflecting duration of sedentary postures); and time spent/d in activities requiring <1.5 MET and <2 MET (reflecting intensity and duration of sedentary time). Cutoff points for sedentarism and their respective prognostic values were investigated for each variable. RESULTS: Forty-one subjects (41%) died over a median (interquartile range) follow-up period of 62 (43-88) months. After adjusting for potential confounders in the Cox regression model, cutoff points from variables that combine duration of sedentary time and intensity <1.5 MET or <2 MET were associated with the increased risk of mortality. The strongest independent cutoff for predicting mortality was ≥8.5 h/d spent in sedentary activities <1.5 MET (area under the curve 0.76; hazard ratio 4.09, 95% CI 1.90-8.78; P < .001). CONCLUSIONS: Sedentary behavior was an independent predictor of mortality in subjects with COPD, even adjusting for moderate-to-vigorous physical activity and a number of other variables. Mortality was higher in subjects with COPD who spend ≥8.5 h/d in activities requiring <1.5 MET. These findings may open room for future studies aiming at decreasing sedentary time as a promising strategy to reduce mortality risk in subjects with COPD.

Development, Validity and Reliability of the Londrina Activities of Daily Living Protocol for Subjects With COPD.

BACKGROUND: To avoid symptoms, patients with COPD may reduce the amount of activities of daily living (ADL). Therefore, the aim of the present study was to develop a standardized protocol to evaluate ADL performance in subjects with COPD (Londrina ADL protocol) and to assess the validity and reliability of the protocol in this population. METHODS: The Londrina ADL protocol was created based on activities included in previous studies aimed at investigating outcomes from ADL. Activities were included in the protocol because they could represent other activities of similar patterns and because they could be actually performed, not simulated. Twenty subjects with COPD (12 men, 70 ± 7 y old, FEV1 = 54 ± 15% predicted) wore 2 motion sensors while performing the protocol 4 times, 2 of them wearing a portable gas analyzer. Subjects were also submitted to assessments of lung function, functional exercise capacity, functional status, impact on health status, and physical activity in daily life. RESULTS: The Londrina ADL protocol comprised of 5 activities representing ADL, involving upper limbs, lower limbs, and trunk movements. Londrina ADL protocol duration presented high values of intraclass correlation coefficient, even using a mask for gas analysis (intraclass correlation coefficient >0.90, P < .001). Intensity of movement during the protocol performance was highly correlated to intensity of movement in daily life (r = 0.71). The protocol duration was correlated with functional status and impact on health status variables from questionnaires (0.36 ≤ r ≤ 0.59). There was also correlation between functional exercise capacity and the protocol duration (r = -0.64). CONCLUSIONS: The Londrina ADL protocol was a valid and reliable protocol to evaluate ADL performance in subjects with COPD. It is a protocol that can be used in clinical practice and in future studies to investigate ADL outcomes, including those studies that require gas analysis and the wearing of a mask.

Profile of patients with chronic obstructive pulmonary disease classified as physically active and inactive according to different thresholds of physical activity in daily life

ABSTRACT Objective To compare the profiles of patients with chronic obstructive pulmonary disease (COPD) considered physically active or inactive according to different classifications of the level of physical activity in daily life (PADL). Method Pulmonary function, dyspnea, functional status, body composition, exercise capacity, respiratory and peripheral muscle strength, and presence of comorbidities were assessed in 104 patients with COPD. The level of PADL was quantified with a SenseWear Armband activity monitor. Three classifications were used to classify the patients as physically active or inactive: 30 minutes of activity/day with intensity >3.2 METs, if age ≥65 years, and >4 METs, if age <65 years; 30 minutes of activity/day with intensity >3.0 METs, regardless of patient age; and 80 minutes of activity/day with intensity >3.0 METs, regardless of patient age. Results In all classifications, when compared with the inactive group, the physically active group had better values of anthropometric variables (higher fat-free mass, lower body weight, body mass index and fat percentage), exercise capacity (6-minute walking distance), lung function (forced vital capacity) and functional status (personal care domain of the London Chest Activity of Daily Living). Furthermore, patients classified as physically active in two classifications also had better peripheral and expiratory muscle strength, airflow obstruction, functional status, and quality of life, as well as lower prevalence of heart disease and mortality risk. Conclusion In all classification methods, physically active patients with COPD have better exercise capacity, lung function, body composition, and functional status compared to physically inactive patients.

Profile of patients with chronic obstructive pulmonary disease classified as physically active and inactive according to different thresholds of physical activity in daily life.

Objective: To compare the profiles of patients with chronic obstructive pulmonary disease (COPD) considered physically active or inactive according to different classifications of the level of physical activity in daily life (PADL). Method: Pulmonary function, dyspnea, functional status, body composition, exercise capacity, respiratory and peripheral muscle strength, and presence of comorbidities were assessed in 104 patients with COPD. The level of PADL was quantified with a SenseWear Armband activity monitor. Three classifications were used to classify the patients as physically active or inactive: 30 minutes of activity/day with intensity >3.2 METs, if age ≥65 years, and >4 METs, if age <65 years; 30 minutes of activity/day with intensity >3.0 METs, regardless of patient age; and 80 minutes of activity/day with intensity >3.0 METs, regardless of patient age. Results: In all classifications, when compared with the inactive group, the physically active group had better values of anthropometric variables (higher fat-free mass, lower body weight, body mass index and fat percentage), exercise capacity (6-minute walking distance), lung function (forced vital capacity) and functional status (personal care domain of the London Chest Activity of Daily Living). Furthermore, patients classified as physically active in two classifications also had better peripheral and expiratory muscle strength, airflow obstruction, functional status, and quality of life, as well as lower prevalence of heart disease and mortality risk. Conclusion: In all classification methods, physically active patients with COPD have better exercise capacity, lung function, body composition, and functional status compared to physically inactive patients.

GOLD B-C-D groups or GOLD II-III-IV grades: Which one better reflects the functionality of patients with chronic obstructive pulmonary disease?

The aim of this article is to investigate which global initiative for chronic obstructive lung disease (GOLD) classification (B-C-D or II-III-IV) better reflects the functionality of patients with moderate to very severe chronic obstructive pulmonary disease (COPD). Ninety patients with COPD were classified according to the GOLD B-C-D and II-III-IV classifications. Functionality was assessed by different outcomes: 6-min walk test (6MWT), activities of daily living (ADL) (London Chest ADL Scale), and daily life activity/inactivity variables assessed by activity monitoring (SenseWear armband, Pittsburgh, Pennsylvania, USA). The 6MWT was the only outcome significantly associated with both the GOLD classifications. Good functionality as assessed by the 6MWT was observed in 80%, 69%, and 43.5% (GOLD B, C, and D, respectively) and 81%, 59%, and 29% (GOLD II, III, and IV, respectively) of the patients. Association (V Cramer's) and correlation (Spearman) coefficients of 6MWT with GOLD B-C-D and II-III-IV were V = 0.30, r = -0.35, and V = 0.37, r = -0.25, respectively. Neither GOLD classification showed V or r ≥ 0.30 with any other functionality outcome. Both the GOLD B-C-D and II-III-IV classifications do not reflect well COPD patients' functionality. Despite low association and correlation coefficients in general, both GOLD classifications were better associated with functional exercise capacity (6MWT) than with subjectively assessed ADL and objectively assessed outcomes of physical activity/inactivity.

Long-term effects of a program to increase physical activity in smokers.

BACKGROUND: Programs aimed at increasing physical activity in daily life (PADL) have generated growing interest to prevent the deleterious effects of physical inactivity. Recent literature has shown that a short-term protocol using pedometers increased PADL in smokers with normal lung function. However, the long-term effects of such a protocol were not yet studied. The objective of this study was to evaluate the results of 1-year follow-up after a program aimed at increasing PADL in smokers with normal lung function. METHODS: Twenty-four smokers were followed (15 men; mean [interquartile range (IQR)], 51 [41-57] years of age; BMI, 26 [22-29] kg/m2; 20 [20-30] cigarettes/d). Subjects were assessed at baseline, immediately after completion of the program, and 1 year later for PADL, lung function, 6-min walking distance (6MWD), smoking habits, quality of life, anxiety, and depression. The 5-month program used pedometers and informative booklets as interventions. RESULTS: The gains achieved after the program were maintained in the long term: steps/d (postprogram vs 1-year follow-up, mean [IQR]: 10,572 [9,804-12,237] vs 10,438 [9,151-12,862]); 6MWD (625 [530-694] m, 88 [81-97] % predicted vs 609 [539-694] m, 89 [81-96] % predicted), anxiety (34 [26-41] points vs 35 [36-47] points) and depression (6 [2-9] points vs 5 [2-11] points) (P > .05 for all). One year after the program, 20% of the subjects had quit smoking. CONCLUSIONS: In smokers with normal lung function, improvements in daily physical activity, exercise capacity, anxiety, and depression obtained through a 5-month program aimed at increasing physical activity are sustained 1 year after completion of the program. Furthermore, such a program can contribute to smoking cessation in this population.

Step counting and energy expenditure estimation in patients with chronic obstructive pulmonary disease and healthy elderly: accuracy of 2 motion sensors.

OBJECTIVE: To compare the accuracy of 2 motion sensors (a pedometer and a multisensor) in terms of step counting and estimation of energy expenditure (EE) in patients with chronic obstructive pulmonary disease (COPD) and in healthy elderly. DESIGN: In this descriptive study, all participants wore both motion sensors while performing a treadmill walking protocol at 3 different speeds corresponding to 30%, 60%, and 100% of the average speed achieved during a six-minute walk test. As criterion methods, EE was estimated by indirect calorimetry, and steps were registered by videotape. SETTING: Research laboratory at a university hospital. PARTICIPANTS: Patients with COPD (n=30; 17 men; mean age +/- SD, 67+/-8 y; mean forced expiratory volume in the first second [FEV(1)] predicted +/- SD, 46%+/-17%; mean body mass index [BMI] +/- SD, 24+/-4 kg.m(2)) and matched healthy elderly (n=30; 15 men; mean age +/- SD, 68+/-7 y; mean FEV(1) predicted +/- SD, 104%+/-21%; mean BMI +/- SD, 25+/-3 kg.m(2)). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: Step counting and EE estimation during a treadmill walking protocol. RESULTS: The pedometer was accurate for step counting and EE estimation in both patients with COPD and healthy elderly at the higher speed. However, it showed significant underestimation at the 2 slower speeds in both groups. The multisensor did not detect steps accurately at any speed, although it accurately estimated EE at all speeds in healthy elderly and at the intermediate and higher speeds in patients with COPD. CONCLUSIONS: In both patients with COPD and healthy elderly, the multisensor showed better EE estimates during most walking speeds than the pedometer. Conversely, for step counting, accuracy is observed only with the pedometer during the higher walking speed in both groups.