Effects of physical activity on exercise tests and respiratory function

The longitudinal association between adverse childhood experiences, childhood socioeconomic status, and lung function among middle-aged and older adults

OBJECTIVES

This study aims to investigate the association between adverse childhood experiences (ACEs), childhood socioeconomic status (SES) with lung function among general Chinese middle-aged and older adults.

METHODS

Participants at baseline were 9052 individuals aged 45 years old and above from the China Health and Retirement Longitudinal Study (CHARLS), a population-based cohort of Chinese adults. Analyses were conducted with data from three waves (2011, 2013, and 2015). The ACEs included five threat-related indicators (i.e., physical abuse, household substance abuse, domestic violence, unsafe neighborhood, and bullying) and five deprivation-related adversities (i.e., emotional neglect, household mental illness, incarcerated household member, parental separation or divorce, and parental death). The cumulative score of threat-related and deprivation-related ACEs was used for analysis. Lung function was assessed by peak expiratory flow (PEF). Two-level linear mixed growth models were used to evaluate the longitudinal association between and ACEs, childhood SES, and PEF.

RESULTS

Participants with more than three deprivation-related ACEs were significantly associated with lower PEF (b = -11.45 L/min, 95%CI: -18.40, -4.49) after adjusting for multiple confounding factors. Threat-related ACEs were not associated with PFF. Father's illiterate education predicted lower lung function (b = -8.49 L/min, 95%CI: -11.68, -5.31) for all middle-aged and older adults while mother's illiterate education was only significantly associated with PEF among the men (b = -9.21 L/min, 95%CI: -18.20, -0.22), and middle-aged adults (b = -7.96 L/min, 95%CI: -14.35, -1.57).

DISCUSSION

ACEs and disadvantaged childhood SES are important predictors of lower lung function during adulthood. Reducing ACEs and improving childhood SES may be beneficial for long-term health development.

Pulmonary responses following cardiac rehabilitation and the relationship with functional outcomes in children and young adults with heart disease

Introduction

Patients with congenital heart disease (CHD) often have pulmonary abnormalities and exercise intolerance following cardiac surgery. Cardiac rehabilitation (CR) improves exercise capacity in patients with CHD, but minimal study has been performed to see if resting and dynamic pulmonary performance improves following CR in those with prior cardiac surgery.

Methods

This was a retrospective cohort study of all patients who completed ≥12 weeks of CR from 2018 through 2022. Demographic, cardiopulmonary exercise test (CPET), spirometry, 6-minute walk, functional strength measures, and outcomes data were collected. Data are presented as median[IQR]. A Student's t-test was used for comparisons between groups and serial measurements were measured with a paired t-test. A p < 0.05 was considered significant.

Results

There were a total of 37 patients [age 16.7 (14.2-20.1) years; 46% male] included. Patients with prior surgery (n = 26) were more likely to have abnormal spirometry data than those without heart disease (n = 11) (forced vital capacity [FVC] 76.7 [69.1-84.3]% vs. 96.4 [88.1-104.7]%, p = 0.002), but neither group experienced a significant change in spirometry. On CPET, peak oxygen consumption increased but there was no change in other pulmonary measures during exercise. Percent predicted FVC correlated with hand grip strength (r = 0.57, p = 0.0003) and percent predicted oxygen consumption (r = 0.43, p = 0.009). The number of prior sternotomies showed negative associations with both percent predicted FVC (r = -0.43, p = 0.04) and FEV1 (r = -0.47, p = 0.02).

Discussion

Youth and young adults with a prior history of cardiac surgery have resting and dynamic pulmonary abnormalities that do not improve following CR. Multiple sternotomies are associated with worse pulmonary function.

Effects of a co-designed exercise and sport intervention on cardiorespiratory fitness and metabolic syndrome components among individuals living in a refugee camp in Greece: A randomized controlled trial

Background

The metabolic syndrome epidemic, including in forcibly displaced individuals, requires cost-effective prevention and treatment strategies. Yet, the health needs of forcibly displaced individuals often remain underserved. Our study evaluated the effect of a co-designed exercise and sport intervention on cardiorespiratory fitness and metabolic syndrome components among individuals in a refugee camp in Greece and examined the indirect effect through cardiorespiratory fitness on metabolic syndrome components.

Methods

We conducted a randomized controlled trial involving an intervention and a wait-list control group with n = 142 (52.8 % women) forcibly displaced Southwest Asians and Sub-Saharan Africans. The intervention group participated for 10 weeks in exercise and sport activities. Outcomes were cardiorespiratory fitness and single metabolic syndrome components. Effects were analyzed with structural equation modeling.

Results

In total, 62.7 % of participants presented with low cardiorespiratory fitness levels (<40th percentile), and 24.6 % met the criteria for metabolic syndrome. In the intervention group, 73.5 % attended the exercise and sport sessions at least once a week. There was evidence for a direct intervention effect on cardiorespiratory fitness, ßdirect = 0.12, p = 0.022, but not for any of the metabolic syndrome components (p ≥ 0.192). Cardiorespiratory fitness significantly facilitated the intervention's indirect effect on abdominal obesity, ßindirect = -0.03, p = 0.012, high diastolic blood pressure, ßindirect = -0.04, p = 0.011, and elevated triglycerides, ßindirect = -0.03, p = 0.025.

Conclusion

Implementing exercise and sport activities in a refugee camp in Greece effectively reaches a wider target population and improves cardiorespiratory fitness among forcibly displaced individuals. The intervention contributes to a decrease in abdominal obesity, high diastolic blood pressure and elevated triglycerides indirectly via improved cardiorespiratory fitness.

Physical activity and Physical fitness in Prediction of all-cause Mortality and Age at Death in European Extinct Cohorts of middle-aged men followed for 60 Years

BACKGROUND

A study of the power of physical activity (Phyac) and physical fitness (Fitscore) in predicting very long-term all-cause mortality and age at death (AD) is missing.

METHODS

A total of 5,482 middle-aged men were examined with measurement of several risk factors and followed for 60 years until virtual extinction of cohorts. Phyac in 3 classes was estimated from their type of work while Fitscore was derived from the linear combinations of levels of arm circumference, heart rate and vital capacity computed as a factor score by principal components analysis. Predictive power of these characteristics (adjusted for 5 traditional cardiovascular risk factors) was made by Cox models (for all-cause mortality) and multiple linear regression models (for AD).

RESULTS

Single levels of the 3 indicators of fitness were highly related to the 3 levels of Phyac and of Fitscore. High levels of both Phyac and of Fitscore forced into the same models were associated with lower all-cause mortality and higher AD. Predictive power of Fitscore was systematically better than that of Phyac. Hazard ratios (high versus low) for all-cause mortality were 0.85 (Phyac) and 0.70 (Fitscore). Coefficients (all significant) were 2.25 years (Phyac) and 3.79 of AD by Fitscore. Fitscore was independently and significantly predictive of all-cause mortality for both first and second 30-year follow-up periods.

CONCLUSIONS

Phyac and Fitscore are related and both showed important predictive power for all-cause mortality and AD. The role of Fitscore was more powerful and both characteristics seem to be expressions of health status.

Association of Physical Fitness and Anthropometric Parameters With Lung Function in 7-Year-Old Children

PURPOSE

Associations between health-related parameters and lung function remain unclear in childhood. The study aims to evaluate the relationship between physical fitness and anthropometric parameters with the lung function of healthy scholar-aged children.

METHOD

A total of 418 children aged 7 years old participated in this study. The associations of physical fitness (handgrip strength, standing broad jump, and 800-m run) and anthropometric (waist circumference and body mass index) parameters with lung function (forced vital capacity and forced expiratory volume in 1 s) were analyzed using a mixed-linear regression model.

RESULTS

Girls had significantly lower forced vital capacity values (P = .006) and physical fitness (P < .030) compared to boys. On mixed-linear regression analyses, waist circumference (P = .003) was independently associated with forced vital capacity, explaining 34.6% of its variance, while handgrip strength (P = .042) and waist circumference (P = .010) were independently associated with forced expiratory volume in 1 second, accounting together for 26.5% of its variance in 7-year-old healthy children.

CONCLUSIONS

Handgrip strength and waist circumference were associated with lung function in healthy children highlighting the influence of upper body muscular strength and trunk dimension on lung function. Our results corroborate the need to promote physical fitness during childhood to protect against lung complications in later on in life.

Effect of Swimming Exercise on Respiratory Muscle Strength and Respiratory Functions in Children with Autism

OBJECTIVE

The aim of this study is to examine the effects of swimming exercise on respiratory muscle strength and respiratory functions in children with autism. Autism is a mental disorder that affects many areas such as sensory, cognitive, motor, and psycho-motor development in individuals.

MATERIALS AND METHODS

For this purpose, 15 individuals with autism, 8 of which were in the experimental group and 7 in the control group, participated in the study. The experimental group was subjected to swimming exercise for 1 hour, 3 days a week, for 6 weeks. The control group was not included in this exercise. Respiratory muscle strength and pulmonary function tests were applied to both groups before and after the 6-week period. The obtained data were analyzed using Statistical Package for Social Sciences Program Version 22.0. Values were presented as minimum, maximum, mean, standard deviation, and standard error. The Shapiro-Wilk test was used to test for normality. Paired-sample t-test was used for pre-test and post-test, and independent-sample t-test was used for intergroup analysis.

RESULTS

At the end of 6 weeks, according to the statistical analysis data, there was a significant difference in some of the respiratory function parameters of the experimental group (P < .05), and an improvement was observed in the respiratory muscle strength values, but no significant difference was found (P > .05). No significant difference was found in the respiratory functions of the control group as a result of respiratory muscle strength measurements (P > .05).

CONCLUSION

As a result, we can say that swimming exercise is effective in improving respiratory muscle strength and respiratory functions in children with autism.

Objective Measurement of Physical Activity and Sedentary Behavior in Patients with Chronic Obstructive Pulmonary Disease: Points to Keep in Mind during Evaluations

Objective measurement methods using accelerometers have become the mainstream approach for evaluating physical activity (PA) and sedentary behavior (SB). However, several problems face the objective evaluation of PA and SB in patients with chronic obstructive pulmonary disease (COPD). For example, indicators of PA differ depending on whether the accelerometer detects the kind of activity on the one hand, or its intensity on the other. Measured data are also strongly influenced by environmental factors (weather, season, employment status, etc.) and methodological factors (days with uncommon activities, non-wearing time, minimum required wearing time per day, minimum number of valid days required, etc.). Therefore, adjusting for these factors is required when evaluating PA or SB, especially when evaluating the effects of intervention. The exclusion of sleeping time, unification of total measurement time, and minimization of the required wearing time per day might be more important for the evaluation of ST than for evaluating PA. The lying-down-time-to-sitting-time ratio was shown to be larger in COPD patients than in healthy subjects. In this review, we clarified the problems encountered during objective evaluations of PA and SB in patients with COPD and encouraged investigators to recognize the presence of these problems and the importance of adjusting for them.

Six Months of Exercise Training Improves Ventilatory Responses during Exercise in Adults with Well-Healed Burn Injuries

INTRODUCTION

Pulmonary function is lower after a severe burn injury, which could influence ventilatory responses during exercise. It is unclear whether exercise training improves pulmonary function or ventilatory responses during exercise in adults with well-healed burn injuries. Therefore, we tested the hypothesis that exercise training improves pulmonary function and ventilatory responses during exercise in adults with well-healed burn injuries.

METHODS

Thirty-nine adults (28 with well-healed burn injuries and 11 non-burn-injured controls) completed 6 months of unsupervised, progressive exercise training including endurance, resistance, and high-intensity interval components. Before and after exercise training, we performed comprehensive pulmonary function testing and measured ventilatory responses during cycling exercise. We compared variables using two-way ANOVA (group-time; i.e., preexercise/postexercise training (repeated factor)).

RESULTS

Exercise training did not increase percent predicted spirometry, lung diffusing capacity, or airway resistance measures (time: P ≥ 0.14 for all variables). However, exercise training reduced minute ventilation ( V̇E ; time: P ≤ 0.05 for 50 and 75 W) and the ventilatory equivalent for oxygen ( V̇E /V̇O 2 ; time: P < 0.001 for 75 W) during fixed-load exercise for both groups. The ventilatory equivalent for carbon dioxide ( V̇E /V̇CO 2 ) during exercise at 75 W was reduced after exercise training (time: P = 0.04). The percentage of age-predicted maximum heart rate at the ventilatory threshold was lower in adults with well-healed burn injuries before ( P = 0.002), but not after ( P = 0.22), exercise training. Lastly, exercise training increased V̇E and reduced V̇E /V̇O 2 during maximal exercise (time: P = 0.005 for both variables).

CONCLUSIONS

These novel findings demonstrate that exercise training can improve ventilatory responses during exercise in adults with well-healed burn injuries.

Effectiveness of respiratory rehabilitation in patients with COVID-19: A meta-analysis

AIM

Examine effectiveness of respiratory rehabilitation and moderating factors on lung function and exercise capacity in post-COVID-19 patients.

DESIGN

Meta-analysis.

METHODS

R software 4.0.2 assessed the effectiveness of respiratory rehabilitation adopting the random-effects model and presenting standardised mean differences (SMDs). Heterogeneity was determined by Cochran's Q and I² . The Cochrane Risk of Bias 2.0 and MINORS evaluated quality of the included studies.

DATA SOURCES

A comprehensive search was undertaken in Cochrane, Embase, Ovid-MEDLINE, Scopus, NCBI SARS-CoV-2 Resources, ProQuest, Web of Science and CINAHL until March 2022.

RESULTS

Of the 5703 identified studies, 12 articles with 596 post-COVID-19 patients were included. Eleven of our twelve studies had moderate to high quality and one study had high risk of bias assessed with MINORS and RoB 2 tool. Overall, respiratory rehabilitation was effective in improving forced expiratory volume in 1 s (1.14; 95%CI 0.39-1.18), forced vital capacity (0.98; 95%CI 0.39-1.56), total lung capacity (0.83; 95%CI 0.22-1.44), 6-minute walk distance (1.56; 95%CI 1.10-2.02) and quality of life (0.99; 95%CI 0.38-1.60). However, no significant differences were observed for ratio of the forced expiratory volume in 1 s to the forced vital capacity of the lungs, anxiety and depression. Respiratory rehabilitation for post-COVID-19 patients was effective in those without comorbidities, performed four types of exercise programs, frequency ≥3 times/week and rehabilitation time 6 weeks.

CONCLUSIONS

Respiratory rehabilitation improved lung function, exercise capacity and quality of life in post-COVID-19 patients. The findings suggest rehabilitation programs for post-COVID-19 patients should use multiple respiratory exercise programs with frequency of ≥3 times per week for longer than 6 weeks.

IMPACT

These findings will help improve the implementation of respiratory rehabilitation programs for post-COVID-19 patients.

IMPLICATIONS FOR THE PROFESSION

Our findings can be used to develop patient-centred respiratory rehabilitation interventions by nurses and clinicians for post-COVID-19 patients.

REPORTING METHOD

PRISMA guideline was followed.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution.

Sedentary behaviour, but not moderate-to-vigorous physical activity, is associated with respiratory responses to acute psychological stress

BACKGROUND

Acute psychological stress induces respiratory responses, and stress-induced respiratory changes can be used to non-invasively reflect metabolic regulation. Respiratory and cardiovascular responses to stress are both driven by sympathetic mechanisms. Higher volumes of sedentary behaviour and lower volumes of physical activity are associated with elevated sympathetic tone and larger cardiovascular responses to stress. The aim of this study was to test whether these associations translate to measures of respiratory stress reactivity.

METHODS

Daily hours of sedentary behaviour (thigh-mounted activPAL) and moderate-to-vigorous physical activity (MVPA; wrist-mounted ActiGraph) were assessed across seven days. Breath-by-breath respiratory (e.g., breathing frequency [BF], end-tidal carbon dioxide partial pressure [PetCO₂], carbon dioxide output [V̇CO₂] and respiratory exchange ratio [RER]) responses to an 8-min Paced Auditory Serial Addition Test were then measured using a Cortex MetaLyzer3B.

RESULTS

Healthy participants (N = 61, mean age ± SD = 25.7 ± 8.9 years) recorded high volumes of sedentary behaviour (9.96 ± 1.48 h/day) and MVPA (1.70 ± 0.71 h/day). In adjusted models (with the inclusion of sedentary behaviour, MVPA, and other a priori selected covariates) hours of daily sedentary behaviour were associated with baseline to stress changes in BF (Β = 0.695, 95% CI = 0.281 - 1.109, p = .014), V_T (Β = -0.042, 95% CI = -0.058 - -0.026, p = .014), PetCO₂ (Β = -0.537, 95% CI = -0.829 - -0.245, p = .014), V̇CO₂ (Β = -0.008, 95% CI = -0.014 - -0.003, p = .030), and RER (Β = -0.013, 95% CI = -0.021 - -0.005, p = .022). Daily hours of MVPA were not linked with respiratory responses to stress.

DISCUSSION

Sedentary behaviour, but not MVPA, is associated with respiratory stress reactivity. Future work should untangle the underlying mechanisms of these findings and explore the consequences for cardiometabolic disease.

Associations of cardiorespiratory fitness and body mass index with incident restrictive spirometry pattern

OBJECTIVES

Restrictive spirometry pattern (RSP) suggests an impairment of lung function associated with a significantly increased risk of premature mortality. We evaluated the independent and joint associations of cardiorespiratory fitness (CRF) and body mass index with incident RSP.

METHODS

Data from the Aerobics Centre Longitudinal Study included 12 360 participants (18-82 years). CRF was assessed by maximal treadmill test and categorised into five groups. Body mass index was categorised into normal weight (<25.0 kg/m²), overweight (25.0-29.9 kg/m²) or obesity (≥30.0 kg/m²). RSP was defined as the simultaneous occurrence of forced expiratory volume in 1 s/force vital capacity ≥lower limit of normal and forced vital capacity <lower limit of normal.

RESULTS

There were 900 (7.3%) cases of RSP (mean follow-up: 6.9 years). Compared with category 1 ('least fit'), HRs (95% CIs) of RSP were 0.78 (0.63 to 0.96), 0.68 (0.54 to 0.86), 0.70 (0.55 to 0.88) and 0.59 (0.45 to 0.77) in categories 2, 3, 4 and 5 (most fit), respectively, after adjusting for confounders including body mass index. Compared with normal weight, HRs (95% CIs) of RSP were 1.06 (0.91 to 1.23) and 1.30 (1.03 to 1.64) in overweight and obese, respectively. However, the association between obesity and RSP was attenuated when additionally adjusting for CRF (HR 1.08, 95% CI 0.84 to 1.39). Compared with the 'unfit and overweight/obese' group, HRs (95% CIs) for RSP were 1.35 (0.98 to 1.85), 0.77 (0.63 to 0.96) and 0.70 (0.56 to 0.87) in the 'unfit and normal weight,' 'fit and overweight/obese' and 'fit and normal weight' groups, respectively.

CONCLUSIONS

Low CRF was associated with a greater incidence of RSP, irrespective of body mass index. Future studies are needed to explore potential underlying mechanisms of this association and to prospectively evaluate if improving CRF reduces the risk of developing RSP.

Machine learning approaches to predict age from accelerometer records of physical activity at biobank scale

Physical activity improves quality of life and protects against age-related diseases. With age, physical activity tends to decrease, increasing vulnerability to disease in the elderly. In the following, we trained a neural network to predict age from 115,456 one week-long 100Hz wrist accelerometer recordings from the UK Biobank (mean absolute error = 3.7±0.2 years), using a variety of data structures to capture the complexity of real-world activity. We achieved this performance by preprocessing the raw frequency data as 2,271 scalar features, 113 time series, and four images. We defined accelerated aging for a participant as being predicted older than one's actual age and identified both genetic and environmental exposure factors associated with the new phenotype. We performed a genome wide association on the accelerated aging phenotypes to estimate its heritability (h_g2 = 12.3±0.9%) and identified ten single nucleotide polymorphisms in close proximity to genes in a histone and olfactory cluster on chromosome six (e.g HIST1H1C, OR5V1). Similarly, we identified biomarkers (e.g blood pressure), clinical phenotypes (e.g chest pain), diseases (e.g hypertension), environmental (e.g smoking), and socioeconomic (e.g income and education) variables associated with accelerated aging. Physical activity-derived biological age is a complex phenotype associated with both genetic and non-genetic factors.

Impact of Body Composition Parameters on Lung Function in Athletes

Background: Given the potential risk of unhealthy weight management, the monitoring of body composition in athletes is advised. However, limited data reveal how body composition measurements can benefit athlete health and, in particular, respiratory function. The aim of this study is to evaluate the impact of body composition on pulmonary function in a population of adult athletes. Methods: Data from 435 competitive adult athletes regarding body compositions parameters and spirometry are retrospectively analyzed. Results: Our study population consists of 335 males and 100 female athletes. Muscle mass and fat-free mass are significantly and positively associated with forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) in the male and female population, while waist-to-height ratio is negatively associated with FEV1, FVC, and FEV1/FVC in the male population. In multivariable analysis, muscle mass and fat-free mass show significant association with FEV1 and FVC in both males and females (p < 0.05), and waist-to-height ratio is significantly and inversely associated with FEV1 and FVC in males (p < 0.05). Conclusions: Fat-free mass and muscle mass are positively and independently associated with FEV1 and FVC in athletes of both genders, and waist-to-height ratio is inversely associated with FEV1 and FVC only among male athletes. These findings suggest that body composition in athletes may be helpful in monitoring respiratory function.

Assessment of Factors Influencing Personal Exposure to Air Pollution on Main Roads in Bogota: A Mixed-Method Study

Background and Objectives: Particulate Matter (PM), particles of variable but small diameter can penetrate the respiratory system via inhalation, causing respiratory and/or cardiovascular diseases. This study aims to evaluate the association of environmental particulate matter (PM_2.5) and black carbon (BC) with respiratory health in users of different transport modes in four roads in Bogotá. Materials and Methods: this was a mixed-method study (including a cross sectional study and a qualitative description of the air quality perception), in 300 healthy participants, based on an exploratory sequential design. The respiratory effect was measured comparing the changes between pre- and post-spirometry. The PM_2.5 and black carbon (BC) concentrations were measured using portable devices. Inhaled doses were also calculated for each participant according to the mode and route. Perception was approached through semi-structured interviews. The analysis included multivariate models and concurrent triangulation. Results: The concentration of matter and black carbon were greater in bus users (median 50.67 µg m^-3; interquartile range (-IR): 306.7). We found greater inhaled dosages of air pollutants among bike users (16.41 µg m^-3). We did not find changes in the spirometry parameter associated with air pollutants or transport modes. The participants reported a major sensory influence at the visual and olfactory level as perception of bad air quality. Conclusions: We observed greater inhaled doses among active transport users. Nevertheless, no pathological changes were identified in the spirometry parameters. People's perceptions are a preponderant element in the assessment of air quality.

Cardiovascular disease in chronic obstructive pulmonary disease: a narrative review

Patients with chronic obstructive pulmonary disease (COPD) are at increased risk of cardiovascular disease (CVD) and concomitant disease leads to reduced quality of life, increased hospitalisations and worse survival. Acute pulmonary exacerbations are an important contributor to COPD burden and are associated with increased cardiovascular (CV) events. Both COPD and CVD represent a significant global disease impact and understanding the relationship between the two could potentially reduce this burden. The association between CVD and COPD could be a consequence of (1) shared risk factors (environmental and/or genetic) (2) shared pathophysiological pathways (3) coassociation from a high prevalence of both diseases (4) adverse effects (including pulmonary exacerbations) of COPD contributing to CVD and (5) CVD medications potentially worsening COPD and vice versa. CV risk in COPD has traditionally been associated with increasing disease severity, but there are other relevant COPD subtype associations including radiological subtypes, those with frequent pulmonary exacerbations and novel disease clusters. While the prevalence of CVD is high in COPD populations, it may be underdiagnosed, and improved risk prediction, diagnosis and treatment optimisation could lead to improved outcomes. This state-of-the-art review will explore the incidence/prevalence, COPD subtype associations, shared pathophysiology and genetics, risk prediction, and treatment of CVD in COPD.

The Possible Impact of COVID-19 on Respiratory Muscles Structure and Functions: A Literature Review

The impact of SARS-CoV-2 infection on respiratory muscle functions is an important area of recent enquiry. COVID-19 has effects on the respiratory muscles. The diaphragm muscle is perturbed indirectly due to the mechanical-ventilation-induced-disuse, but also by direct mechanisms linked with SARS-CoV-2 viral infection. In this sense, a deeper understanding of the possible links between COVID-19 and alterations in structure and functions of the respiratory muscles may increase the success rate of preventive and supportive strategies. Ultrasound imaging alongside respiratory muscle strength tests and pulmonary function assessment are valid approaches to the screening and monitoring of disease, for mild to severe patients. The aim of the present review is to highlight the current literature regarding the links between COVID-19 and respiratory muscle functions. We examine from the pathophysiological aspects of disease, up to approaches taken to monitor and rehabilitate diseased muscle. We hope this work will add to a greater understanding of the pathophysiology and disease management of respiratory muscle pathology subsequent to SARS-CoV-2 infection.

Multimorbidity patterns and associated factors in older Chinese: results from the China health and retirement longitudinal study

Background

This study aimed to investigate multimorbidity patterns and their associated factors among elderly population in China.

Methods

A total of 10,479 participants aged at least 60 years were drawn from the 2018 wave of the China Health and Retirement Longitudinal Study (CHARLS). Latent class analysis (LCA) was performed to identify distinct multimorbidity classes based on 14 self-reported chronic conditions. The multinomial logit model was used to analyze the associated factors of multimorbidity patterns, focusing on individuals' demographic characteristics, socioeconomic status (SES), and health behaviors.

Results

Among the 10,479 participants (mean age [SD]: 69.1 [7.1]), 65.6% were identified with multimorbidity. Five multimorbidity clusters were identified by LCA: relatively healthy class (49.8%), vascular class (24.7%), respiratory class (5.6%), stomach-arthritis class (14.5%), and multisystem morbidity class (5.4%). Multinomial logit analysis with the relatively healthy class as the reference showed that participants of older age and female sex were more likely to be in the vascular class and multisystem morbidity class. The probability of being in the vascular class was significantly higher for those with high SES. Ever smoking was associated with a higher probability of being in the respiratory class and multisystem morbidity class. Physical activity was associated with lower odds of being assigned to the vascular class, respiratory class, and multisystem class.

Conclusion

The distinct multimorbidity patterns imply that the prevention and care strategy should target a group of diseases instead of a single condition. Prevention interventions should be paid attention to for individuals with risk factors.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12877-022-03154-9.

Cathepsin B and Muscular Strength are Independently Associated with Cognitive Control

Although muscular strength has been linked to greater cognitive function across different cognitive domains, the mechanism(s) through which this occurs remain(s) poorly understood. Indeed, while an emerging body of literature suggests peripheral myokines released from muscular contractions may play a role in this relationship, additional research is needed to understand this link. Accordingly, this study sought to compare the influences of a particular myokine, Cathepsin B (CTSB), and muscular strength on hippocampal-dependent relational memory and cognitive control in 40 adults (age = 50.0±7.3 yrs). Overnight fasted venous blood draws were taken to assess plasma CTSB and muscular strength was assessed as maximal isokinetic strength testing using a Biodex dynamometer. Cognitive performance was assessed using a Spatial Reconstruction Task to assess relational memory and a modified Flanker task to assess cognitive control. Neuroelectric function for cognitive control was assessed using event-related potentials (ERPs) recorded during the Flanker task. Initial bivariate correlational analyses revealed that neither sex, age, lean body mass, or muscular strength was associated with CTSB. However, CTSB was inversely associated with reaction time and fractional peak latency of the P3 component of the Flanker task. Muscular strength was also inversely associated with reaction time and positively associated with relational memory performance. However, the influence of muscular strength on relational memory did not persist following adjustment for covariates. Greater circulating CTSB was selectively associated with greater cognitive control as well as faster information processing speed. These findings are the first to link circulating CTSB to both cognitive control and neuroelectric function. Future intervention studies are needed to examine the effects of changes in muscular strength, circulating myokines, and different domains of cognitive function.

Changes in Physical Fitness and Body Composition Associated with Physical Exercise in Patients with Myasthenia Gravis: A Longitudinal Prospective Study

There is a lack of guidelines for physical exercise in patients with myasthenia gravis (MG). A few pilot studies have shown that exercise can be safely applied to patients with MG. However, how physical exercise affects body composition, disease function, and disease severity remains unknown. In this prospective study, we enrolled 34 patients with MG with stable condition and evaluated the disease severity, physical fitness parameters, and body composition (measured using whole-body dual-energy X-ray absorptiometry (DXA)), before and after conducting a 24-week physical exercise regimen of aerobic and resistance strength training. The outcomes were measured by DXA, quantitative MG (QMG) score, quality of life score, handgrip strength and walking speed. During the training regimen, participants were free to decide how many exercise sessions per week and regularly reported their weekly exercise time. The physical exercise program was well tolerated by the participants, the parameters of the QMG score and handgrip strength improved, and participants’ body composition did not change significantly. The high exercise group experienced greater deterioration in muscle mass in the arms, but exhibited a greater improvement in forced vital capacity, walking speed, and symptom severity. The group with low QMG scores improved more in terms of physical fitness, including walking speed. These findings indicate that physical exercise is well tolerated by patients with MG, and is accompanied by improved muscular and physical functions. We propose that physical exercise is safe, effective, and appropriate for patients with well-regulated MG.

Association between Cardiorespiratory Fitness and Bronchiectasis at CT: A Long-term Population-based Study of Healthy Young Adults Aged 18-30 Years in the CARDIA Study

Background Protective factors against the risk of bronchiectasis are unknown. A high level of cardiorespiratory fitness is associated with a lower risk of chronic obstructive pulmonary disease. But whether fitness relates to bronchiectasis remains, to the knowledge of the authors, unknown. Purpose To examine the association between cardiorespiratory fitness and bronchiectasis. Materials and Methods This was a secondary analysis of a prospective observational study: the Coronary Artery Risk Development in Young Adults cohort (from 1985-1986 [year 0] to 2015-2016 [year 30]). During a 30-year period, healthy participants (age at enrollment 18-30 years) underwent treadmill exercise testing at year 0 and year 20 visits. Cardiorespiratory fitness was determined according to the treadmill exercise duration. The 20-year difference in cardiorespiratory fitness was used as the fitness measurement. At year 25, chest CT was performed to assess bronchiectasis and was used as the primary outcome. Multivariable logistic models were performed to determine the association between cardiorespiratory fitness changes and bronchiectasis. Results Of 2177 selected participants (at year 0: mean age, 25 years ± 4 [standard deviation]; 1224 women), 209 (9.6%) had bronchiectasis at year 25. After adjusting for age, race-sex group, study site, body mass index, pack-years smoked, history of tuberculosis, pneumonia, asthma and myocardial infarction, peak lung function, and cardiorespiratory fitness at baseline, preservation of cardiorespiratory fitness was associated with lower odds of bronchiectasis at CT at year 25 (per 1-minute-longer treadmill duration from year 0 to year 20: odds ratio [OR], 0.88; 95% CI: 0.80, 0.98; P = .02). A consistent strong association was found when cough and phlegm were included in bronchiectasis (OR, 0.72; 95% CI: 0.59, 0.87; P < .001). Conclusion In a long-term follow-up, the preservation of cardiorespiratory fitness was associated with lower odds of bronchiectasis at CT. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Stojanovska in this issue.

Effects of preoperative nutrition and multimodal prehabilitation on functional capacity and postoperative complications in surgical lung cancer patients: a systematic review

OBJECTIVE

To determine the effect of preoperative nutrition and multimodal prehabilitation on clinical and functional outcomes in surgical lung cancer patients.

METHODS

We searched MEDLINE, Cochrane Library and CENTRAL, EMBASE, Scopus, and clinical trial registries ( clinicaltrials.gov , International Clinical Trials Registry Platform and Google Scholar) to identify studies involving a preoperative nutrition-based intervention or multimodal prehabilitation (nutrition with exercise) of at least 7 days, in lung cancer patients awaiting surgery. Studies must have reported results on at least one of the following outcomes: functional capacity, pulmonary function, postoperative complications, and length of hospital stay. The quality of included studies was assessed using the Cochrane risk of bias assessment tool for randomized trials and the modified Newcastle-Ottawa scale for non-controlled trials.

RESULTS

Five studies were included (1 nutrition-only and 4 multimodal prehabilitation studies). Due to substantial heterogeneity in the interventions across studies, a meta-analysis was not conducted. Findings suggest that multimodal prehabilitation, compared with standard hospital care, is associated with improvements in both functional walking capacity and pulmonary function during the preoperative period; however it does not appear to have an effect on postoperative outcomes. Rather, the finding of significantly lower rates of postoperative complications in the intervention group was unique to the nutrition-only study.

CONCLUSION

Multimodal prehabilitation programs that combine nutrition and exercise may have beneficial effects on various physical function outcomes in patients with lung cancer awaiting surgery. Optimizing preoperative nutrition may have postoperative benefits which remain to be confirmed.

The sub-acute effects of high-intensity interval training in healthy young adults: respiratory parameters, aerobic capacity and perceived stress

BACKGROUND

Although the effects of sub-maximal continuous aerobic training (SCT) and high-intensity interval training (HIIT) are well studied in performance athletes and in several patient groups, there is not much evidence about the effects of these exercises in sedentary healthy young population. The aim of the study was to compare the effects of these two different types of aerobic exercises on respiratory parameters, aerobic capacity and perceived stress in healthy university students.

METHODS

Thirty-six healthy, young subjects with a mean age of 20.83±0.97 years were included in the study (N.=19 in HIIT and N.=17 in SCT). Pulmonary function tests (PFTs) and respiratory muscle strength (RMS) assessments were done using a desktop spirometer. Aerobic capacity was estimated with the Bruce treadmill exercise test. The Perceived Stress Scale (PSS) was used for the assessment of stress perception. All participants exercised 3 times per week for 4 weeks (a total of 12 sessions).

RESULTS

After 12 sessions, the peak expiratory flow parameter (a PFT value) of both groups showed significant increases, but there was no difference between the groups. The RMS of the subjects increased significantly in both the groups (P<0.05), but there was no significant difference between the groups. Both groups showed significant increases in terms of aerobic capacity (P>0.05), and the improvement was significantly higher in the HIIT group. Perceived stress values showed a significant increase in the SCT group.

CONCLUSIONS

Based on the results of this study, the two exercise types were found to have similar effects on RMS. Also, when compared with SCT, HIIT was found to have more effect on aerobic capacity.

The Effects of Simultaneous Pulmonary Rehabilitation during Thoracic Radiotherapy in the Treatment of Malignant Diseases

BACKGROUND

Radiotherapy is a common treatment option for lung or esophageal cancer, particularly when surgery is not feasible for patients with poor lung function. However, radiotherapy can affect pulmonary function and thereby induce pneumonitis or pneumonia, which can be fatal in patients with respiratory impairment. The purpose of this study is to evaluate if reductions in pulmonary function after radiotherapy can be minimized through simultaneous pulmonary rehabilitation (PR).

METHODS

In this matched case control study, we retrospectively analyzed patients who had undergone radiotherapy for thoracic malignant disease between January 2018 and June 2019. We analyzed results from pulmonary function tests and 6-minute walking tests (6MWT) conducted within the six months before and after radiotherapy treatment.

RESULTS

In total, results from 144 patients were analyzed, with 11 of the patients receiving PR and radiotherapy simultaneously. Of the 133 patients in the control group, 33 were matched with 11 patients in the PR group. Changes in forced expiratory volume in one second (FEV1) and FEV1/forced vital capacity were significantly different between the PR group and the matched control group (240 mL vs. -10 mL, p=0.017 and 5.5% vs. 1.0%, p=0.038, respectively). The median distance of 6MWT in the PR group also increased significantly, from 407.5 m to 493.0 m after radiotherapy (p=0.017).

CONCLUSION

Simultaneous PR improved pulmonary function, particularly in measures of FEV1, and exercise capacity for patients with lung or esophageal cancer even after radiotherapy treatment. These findings may provide an important base of knowledge for further large population studies with long-term follow-up analysis in the identification of the PR's effects during thoracic radiotherapy.

Data Reproducibility and Effectiveness of Bronchodilators for Improving Physical Activity in COPD Patients

Increasing physical activity (PA) in patients with chronic obstructive pulmonary disease (COPD) is an important issue, however, the effect of bronchodilators on PA is still controversial. The indicators of PA, as measured by an accelerometer, can easily fluctuate based on several factors, which might cause inconsistent results. In this review, we listed the indicators of PA and the factors influencing the reproducibility of indicators of PA, and reviewed reports in which the effects of bronchodilators on PA were evaluated by an accelerometer. Then, we investigated the association between the processing of influencing factors and the effectiveness of bronchodilators for improving the PA of COPD patients. Fifteen reports were extracted using the PubMed database. In all seven reports in which adjustment was performed for at least two of four influencing factors (non-wear time, data from days with special behavior, environmental factors, and number of valid days required to obtain reproducible data), bronchodilators showed beneficial effects on PA. No adjustment was made for any of these factors in any of the four bronchodilator-ineffective reports. This suggests that the processing of influencing factors to secure reproducibility might affect the results regarding the effectiveness of bronchodilators for improving PA in COPD patients.

Cardiorespiratory Fitness as a Correlate of Cardiovascular, Anthropometric, and Physical Risk Factors: Using the Ruffier Test as a Template

Background

Assessment of cardiorespiratory fitness (CRF) is a standard procedure in routine clinical practices. Early identification of risk factors through screening is vital in the fight against chronic diseases. Evaluation of CRF can impose cost implications in the clinical setting; thus, a simple and easy-to-use test is to be advocated. The Ruffier test is a simple test that can assess CRF, and it is necessary to find whether the test reflects the effects of compounding factors in CRF.

Objective

This study aims to determine the association between CRF (estimated VO2max) with cardiovascular, anthropometric, and physical risk factors using the Ruffier test.

Methods

A cross-sectional study with a sample of 52 male participants was conducted. Before the Ruffier test, each participant's body weight, height, waist circumference, skinfold thickness, thigh length, lower-limb length, thigh circumference, physical activity, blood pressure, smoking, diabetes, and pulmonary functions were recorded, and these factors correlated with CRF.

Results

There was a significant inverse relationship found between the estimated VO2max and age, height, body weight, body mass index, waist circumference, a sum of skinfold, fat percentage, thigh length, lower-limb length, thigh circumference, smoking, blood pressure, heart rates, and diabetes (p < 0.05). A significant positive correlation was found between the estimated VO2max with physical activity and respiratory functions (p < 0.05). In the multivariable model, body weight and resting heart rate were significantly inversely associated with the estimated VO2max(p < 0.05).

Conclusion

Using the Ruffier test, various risk factors of CRF are correlated with the estimated VO2max. This test reflects the effects of different compounding factors on CRF; therefore, it can be used in routine clinical practices to identify the risk factors early.

Comparing the effects of six-months aerobic training on pulmonary function tests in obese and nonobese women

BACKGROUND

Obesity is becoming a serious public health issue in the world and is associated with a wide range of health conditions, including respiratory diseases. Prolonged aerobic exercises are thought to improve aerobic capacity and to have a favorable effect on lung function. Thus, the purpose of this study was to determine the comparison the effects of six months of aerobic training on pulmonary function tests in obese and nonobese women.

METHODS

The subjects of this study were nineteen healthy and inactive females assigned into the obese (N.=10) and nonobese (N.=9) groups. The exercise protocol included aerobic exercise training lasted for 6 months and 3 sessions per week and every session lasted for 60 minutes and with intensity of 55-65 percent of maximum heart rate reserve. Before starting program, the anthropometric measurements of subjects such as weight, percent body fat and body mass Index was measured by body composition analyzer and lung function tests were carried out by using a spirometer.

RESULTS

Obese women have lower values of FEV1, FVC, FEV1/FVC, PEF, Vt and MVV when compared with nonobese group but the difference did not reach significant level. Also, the results of this study showed that there are significant differences in FVE1 Index and MVV tests in obese and nonobese groups in pretest and post-test, but FVC Index increased significantly just in obese group.

CONCLUSIONS

It seems that if the training program is done in appropriate time and intensity, which leads to weight loss in obese people, it can lead to improve all Index of pulmonary function.

Physical activity and lung function-Cause or consequence?

Concerns exist that the positive association of physical activity with better lung function, which has been suggested in previous longitudinal studies in smokers, is due to reverse causation. To investigate this, we applied structural equation modeling (SEM), an exploratory approach, and marginal structural modeling (MSM), an approach from the causal inference framework that corrects for reverse causation and time-dependent confounding and estimates causal effects, on data from participants in the European Community Respiratory Health Survey (ECRHS, a multicentre European cohort study initiated in 1991–1993 with ECRHS I, and with two follow-ups: ECRHS II in 1999–2003, and ECRHS III in 2010–2014). 753 subjects who reported current smoking at ECRHS II, with repeated data on lung function at ECRHS I, II and III, physical activity at ECRHS II and III, and potential confounders at ECRHS I and II, were included in the analyses. SEM showed positive associations between physical activity and lung function in both directions. MSM suggested a protective causal effect of physical activity on lung function (overall difference in mean β (95% CI), comparing active versus non-active individuals: 58 mL (21–95) for forced expiratory volume in one second and 83 mL (36–130) for forced vital capacity). Our results suggest bi-directional causation and support a true protective effect of physical activity on lung function in smokers, after accounting for reverse causation and time-dependent confounding.

Association of preoperative spirometry with cardiopulmonary fitness and postoperative outcomes in surgical patients: A multicentre prospective cohort study

BACKGROUND

Preoperative spirometry and cardiopulmonary exercise testing (CPET) may stratify risk for respiratory complications. This secondary analysis of the Measurement of Exercise Tolerance before Surgery (METS) study examined whether CPET performance (i.e., cardiopulmonary fitness) confounds associations of spirometry with outcomes.

METHODS

The analysis included 1200 participants having major non-cardiac surgery at 25 hospitals in Canada, Australia, New Zealand and UK. Forced expiratory volume in 1 s (FEV₁), and ratio of FEV₁ to forced vital capacity (FVC) were measured during preoperative spirometry, and peak oxygen consumption and ventilatory efficiency during preoperative CPET. Outcomes were respiratory morbidity (Postoperative Morbidity Survey) and pulmonary complications (pneumonia or respiratory failure). We used multivariable logistic regression models to estimate associations of FEV₁ with outcomes after adjustment for risk factors and either peak oxygen consumption or ventilatory efficiency.

FINDINGS

128 participants (11%) developed respiratory morbidity, and 48 (4%) developed pulmonary complications. There was no strong evidence that FEV₁ predicted respiratory morbidity after adjustment for peak oxygen consumption (p = 0·80) or ventilatory efficiency (p = 0·76), or FEV₁ predicted pulmonary complications after adjustment for ventilatory efficiency (p = 0·37). Peak oxygen consumption (odds ratio 0·66 per 5 mL/kg/min increase; 95% CI, 0·54-0·82) was associated with respiratory morbidity. Ventilatory efficiency was associated with respiratory morbidity (p = 0·04) and pulmonary complications (p = 0·02). Peak oxygen consumption also confounded the association between FEV₁ and respiratory morbidity.

INTERPRETATION

After accounting for fitness and clinical factors, FEV₁ was not strongly predictive of respiratory complications. Prior associations between FEV₁ and respiratory morbidity may be explained by confounding by peak oxygen consumption.

FUNDING

Canadian Institutes of Health Research, Heart and Stroke Foundation of Canada, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research, Innovation and Science, UK National Institute of Academic Anaesthesia, UK Clinical Research Collaboration, Australian and New Zealand College of Anaesthetists, and Monash University.

Effects of a Virtual Reality Dance Training Program on Kyphosis Angle and Respiratory Parameters in Young Women With Postural Hyperkyphosis: A Randomized Controlled Clinical Trial

CONTEXT

Thoracic hyperkyphosis, one of the most common spinal deformities, may lead to undesirable pulmonary outcomes.

OBJECTIVE

To study, the efficacy of virtual reality exercise training on thoracic hyperkyphosis and respiratory parameters in young women.

DESIGN

Randomized clinical trial.

SETTING

Laboratory setting.

PARTICIPANTS AND INTERVENTION

Participants were randomly assigned to one of two 4-week exercise training groups: regular training (RT), which involved stretch and strength training, or virtual reality with RT (VRRT), which involved dance training with the Xbox 360 Kinect® game in addition to the exercises, which the RT group received.

MAIN OUTCOME MEASURES

The authors measured kyphosis angle with a Flexicurve ruler and recorded respiratory parameters (forced vital capacity [FVC] and forced expiratory volume in 1 s [FEV1]) with a spirometer in each participant at baseline and postintervention. Separate 2 × 2 repeated-measure analysis of variances were used to analyze differences between means for kyphosis angle, FEV1, and FVC. Based on the significant interactions between time and group, the paired t test was used to compare the results at baseline and postintervention, and the independent sample t test was used to compare the differences in changes between groups. Level of significance was considered at P < .05 except for paired t test that was adjusted to P < .025 for each variable in 2 groups.

RESULTS

The results showed statistically significant interactions between time and group for kyphosis angle, FEV1, and FVC. Postintervention thoracic kyphosis angle decreased and FVC increased significantly in both groups and FEV1 improved significantly in virtual reality with RT group. The improvements in thoracic kyphosis, FVC, and FEV1 in the virtual reality with RT group were significantly greater (P < .001) than in the RT group.

CONCLUSION

Dance training with the Xbox 360 Kinect game was an effective therapy in improving thoracic kyphosis angle, FVC, and FEV1 in young women with thoracic hyperkyphosis.

The Effect of Particulate Matter Exposure on the Inflammatory Airway Response of Street Runners and Sedentary People

Physical exercise promotes many health benefits. However, its effects are not well known in a polluted environment. Thus, this study aimed to compare upper airway inflammatory responses between street runners and sedentary individuals. Twenty-eight volunteers were recruited: runners (n = 14) and sedentary individuals (n = 14), who lived and worked in the same metropolitan area of São Paulo, Brazil. Particulate matter (PM) levels were monitored ten weeks before winter (low PM levels) and ten weeks after the beginning of winter (high PM levels) [PM10 (p < 0.0001) and PM2.5 (p < 0.0001)]. The cytokines (TNF-α, IL-6, IL-10, and IL-17A) levels in the nasal lavage and fractional exhaled nitric oxide (FeNO) were taken at the beginning of the winter (baseline) and ten weeks afterwards (after ten weeks of high PM exposure). IL-6 concentration increased in both runners (p = 0.037) and sedentary individuals (p = 0.027) after high PM exposure compared to the baseline. IL-10 concentration increased in sedentary individuals (p = 0.037) while IL-17A levels were increased in runners (p = 0.001) after high PM exposure compared to the baseline. FeNO levels decreased in runners (p = 0.025) after high PM exposure compared to the baseline. Outdoor endurance training acts as an inducer of a differentiated immune response in the upper airways of runners compared to individuals with a sedentary lifestyle from the same community after elevated PM exposure.

The association between accelerometer-assessed physical activity and respiratory function in older adults differs between smokers and non-smokers

The association between physical activity and lung function is thought to depend on smoking history but most previous research uses self-reported measures of physical activity. This cross-sectional study investigates whether the association between accelerometer-derived physical activity and lung function in older adults differs by smoking history. The sample comprised 3063 participants (age = 60–83 years) who wore an accelerometer during 9 days and undertook respiratory function tests. Forced vital capacity (FVC) was associated with moderate-to-vigorous physical activity (MVPA; acceleration ≥0.1 g (gravity)) in smokers but not in never smokers: FVC differences for 10 min increase in MVPA were 58.6 (95% Confidence interval: 21.1, 96.1), 27.8 (4.9, 50.7), 16.6 (7.9, 25.4), 2.8 (−5.2, 10.7) ml in current, recent ex-, long-term ex-, and never-smokers, respectively. A similar trend was observed for forced expiratory volume in 1 second. Functional data analysis, a threshold-free approach using the entire accelerometry distribution, showed an association between physical activity and lung function in all smoking groups, with stronger association in current and recent ex-smokers than in long-term ex- and never-smokers; the associations were evident in never smokers only at activity levels above the conventional 0.1 g MVPA threshold. These findings suggest that the association between lung function and physical activity in older adults is more pronounced in smokers than non-smokers.

Midlife cardiorespiratory fitness and the long-term risk of chronic obstructive pulmonary disease

BACKGROUND

Good midlife cardiorespiratory fitness (CRF) may reduce the risk of chronic obstructive pulmonary disease (COPD). Reverse causation may play a role if follow-up time is short. We examined the association between CRF and both incident COPD and COPD mortality in employed men with up to 46 years follow-up, which allowed us to account for reverse causality.

METHODS

Middle-aged men (n=4730) were recruited in 1970-1971. CRF was determined as VO₂max by ergometer test. Categories of CRF (low, normal, high) were defined as ± 1 Z-score (± 1 SD) above or below the age-adjusted mean. Endpoints were identified through national registers and defined as incident COPD, and death from COPD. Multi-adjusted Cox models and restricted mean survival times (RMST) were performed.

RESULTS

Compared with low CRF, the estimated risk of incident COPD was 21% lower in participants with normal CRF (HR 0.79, 95% CI 0.63 to 0.99) and 31 % lower with high CRF (HR 0.69, 95% CI 0.52 to 0.91). Compared with low CRF, the risk of death from COPD was 35% lower in participants with normal CRF (HR 0.65, 95% CI 0.46 to 0.91) and 62% lower in participants with high CRF (HR 0.38, 95% CI 0.23 to 0.61). RMST showed a delay to incident COPD and death from COPD in the magnitude of 1.3-1.8 years in normal and high CRF vs low CRF. Test for reverse causation did not alter the results.

CONCLUSION

In a population of healthy, middle-aged men, higher levels of CRF were associated with a lower long-term risk of incident COPD and death from COPD.

Eight Weeks of Inspiratory Muscle Training Improves Pulmonary Function in Disabled Swimmers-A Randomized Trial

BACKGROUND

According to the literature, inspiratory muscle fatigue may increase after swimming training (ST). This study aimed to examine the efficacy of 8-week inspiratory muscular training (IMT) in disabled swimmers, combined with standard sports training, on selected parameters of lung ventilation and the function of respiratory muscles.

METHODS

A total of 16 disabled swimming division athletes from Wroclaw's 'Start' Regional Sports Association qualified for the study. The subjects were randomly divided into two groups (ST and IMT). Both groups participated in swimming training for 8 weeks (8 times a week). The IMT group additionally participated in inspiratory muscle training (8 weeks). In all respondents, a functional lung test and the respiratory muscle strength was measured.

RESULTS

After 8 weeks of training, a significant increase in ventilation parameters and respiratory muscle strength was observed only in the IMT group. In ST group 1, a 20% improvement in the strength of inspiratory muscles was achieved.

CONCLUSIONS

The inclusion of IMT is an important element that complements swimming training, allowing for greater increases in lung ventilation parameters and the strength of respiratory muscles in disabled swimmers.

Black Carbon Reduces the Beneficial Effect of Physical Activity on Lung Function

INTRODUCTION

When physical activity is promoted in urban outdoor settings (e.g., walking and cycling), individuals are also exposed to air pollution. It has been reported that short-term lung function increases as a response to physical activity, but this beneficial effect is hampered when elevated air pollution concentrations are observed. Our study assessed the long-term impact of air pollution on the pulmonary health benefit of physical activity.

METHODS

Wearable sensors were used to monitor physical activity levels (SenseWear) and exposure to black carbon (microAeth) of 115 healthy adults during 1 wk in three European cities (Antwerp, Barcelona, London). The experiment was repeated in three different seasons to approximate long-term behavior. Spirometry tests were performed at the beginning and end of each measurement week. All results were averaged on a participant level as a proxy for long-term lung function. Mixed effect regression models were used to analyze the long-term impact of physical activity, black carbon and their interaction on lung function parameters, forced expiratory volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, forced expiratory flow (FEF)25-75, and peak expiratory flow. Interaction plots were used to interpret the significant interaction effects.

RESULTS

Negative interaction effects of physical activity and black carbon exposure on FEV1 (P = 0.07), FEV1/FVC (P = 0.03), and FEF25-75 (P = 0.03) were observed. For black carbon concentrations up to approximately 1 μg·m, an additional MET·h·wk resulted in a trend toward lung function increases (FEV1, FEV1/FVC, and FEF25-75 increased 5.6 mL, 0.1% and 14.5 mL·s, respectively).

CONCLUSIONS

We found that lung function improved with physical activity at low black carbon levels. This beneficial effect decreased in higher air pollution concentrations. Our results suggest a greater need to reduce air pollution exposures during physical activity.

Significance Tests for Boosted Location and Scale Models with Linear Base-Learners

Generalized additive models for location scale and shape (GAMLSS) offer very flexible solutions to a wide range of statistical analysis problems, but can be challenging in terms of proper model specification. This complex task can be simplified using regularization techniques such as gradient boosting algorithms, but the estimates derived from such models are shrunken towards zero and it is consequently not straightforward to calculate proper confidence intervals or test statistics. In this article, we propose two strategies to obtain p-values for linear effect estimates for Gaussian location and scale models based on permutation tests and a parametric bootstrap approach. These procedures can provide a solution for one of the remaining problems in the application of gradient boosting algorithms for distributional regression in biostatistical data analyses. Results from extensive simulations indicate that in low-dimensional data both suggested approaches are able to hold the type-I error threshold and provide reasonable test power comparable to the Wald-type test for maximum likelihood inference. In high-dimensional data, when gradient boosting is the only feasible inference for this model class, the power decreases but the type-I error is still under control. In addition, we demonstrate the application of both tests in an epidemiological study to analyse the impact of physical exercise on both average and the stability of the lung function of elderly people in Germany.

Meta-analysis across Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) consortium provides evidence for an association of serum vitamin D with pulmonary function

The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)-pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D-pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (P race difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (P race difference=0·56). Among EA, the 25(OH)D-FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.

Residential air pollution does not modify the positive association between physical activity and lung function in current smokers in the ECRHS study

BACKGROUND

Very few studies have examined whether a long-term beneficial effect of physical activity on lung function can be influenced by living in polluted urban areas.

OBJECTIVE

We assessed whether annual average residential concentrations of nitrogen dioxide (NO₂) and particulate matter with aerodynamic diameters < 2.5 μm (PM_2.5) and <10 μm (PM₁₀) modify the effect of physical activity on lung function among never- (N = 2801) and current (N = 1719) smokers in the multi-center European Community Respiratory Health Survey.

METHODS

Associations between repeated assessments (at 27-57 and 39-67 years) of being physically active (physical activity: ≥2 times and ≥1 h per week) and forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) were evaluated using adjusted mixed linear regression models. Models were conducted separately for never- and current smokers and stratified by residential long-term NO₂, PM_2.5 mass and PM₁₀ mass concentrations (≤75th percentile (low/medium) versus >75th percentile (high)).

RESULTS

Among current smokers, physical activity and lung function were positively associated regardless of air pollution levels. Among never-smokers, physical activity was associated with lung function in areas with low/medium NO₂, PM_2.5 mass and PM₁₀ mass concentrations (e.g. mean difference in FVC between active and non-active subjects was 43.0 mL (13.6, 72.5), 49.5 mL (20.1, 78.8) and 49.7 mL (18.6, 80.7), respectively), but these associations were attenuated in high air pollution areas. Only the interaction term of physical activity and PM₁₀ mass for FEV₁ among never-smokers was significant (p-value = 0.03).

CONCLUSIONS

Physical activity has beneficial effects on adult lung function in current smokers, irrespective of residential air pollution levels in Western Europe. Trends among never-smokers living in high air pollution areas are less clear.

Short-term effects of physical activity, air pollution and their interaction on the cardiovascular and respiratory system

Physical activity (PA) in urban environments may lead to increased inhalation of air pollutants. As PA and air pollution (AP) have respectively beneficial and detrimental effects on the cardiorespiratory system, the responses to these exposures can interact. Therefore, we assessed the short-term effects of PA, AP and their interaction on a set of subclinical cardiovascular and respiratory outcomes in a panel of healthy adults: heart rate variability (HRV), retinal vessel diameters, lung function and fractional exhaled nitric oxide (FeNO). One hundred twenty two participants measured their PA level and exposure to black carbon (BC), a marker of AP exposure, with wearable sensors during an unscripted week in three different seasons. The study was part of the PASTA project in three European cities (Antwerp: 41 participants, Barcelona: 41 participants, London: 40 participants). At the end of each measurement week, the health outcomes were evaluated. Responses to PA, BC and their interaction were assessed with mixed effect regression models. Separate models were used to account for a 2-h and 24-h time window. During the 2-h time window, HRV and lung function changed statistically significantly in response to PA (METhours) and logarithmic BC (%change). Changes in HRV marked an increased sympathetic tone with both PA (logarithmic LF/HF: +7%; p < 0.01) and BC (logarithmic HF: -19%; p < 0.05). In addition, PA provoked bronchodilation which was illustrated by a significant increase in lung function (FEV₁: +15.63 mL; p < 0.05). While a BC %increase was associated with a significant lung function decrease (PEF: -0.10 mL; p < 0.05), the interaction indicated a potential protective effect of PA (p < 0.05). We did not observe a response of the retinal vessel diameters. Most subclinical outcomes did not change in the 24-h time window (except for a few minor changes in LF/HF, FeNO and PEF). Our results on the separate and combined effects of short-term PA and AP exposure on subclinical markers of the cardiorespiratory system are relevant for public health. We provide insights on the physiological responses of multiple, complementary markers. This may move further research towards elucidating potential pathways to disease and the long-term clinical impact of the observed physiological changes.

Association of Time to First Morning Cigarette and Chronic Obstructive Pulmonary Disease Measured by Spirometry in Current Smokers

Background

Time to first cigarette after waking is an indicator of nicotine dependence. We aimed to identify the association between time to first cigarette and spirometry-proven obstructive respiratory impairment, especially chronic obstructive pulmonary disease, in current smokers.

Methods

We included 392 subjects who visited the comprehensive medical examination center of Hallym University Sacred Heart Hospital between July 2014 and September 2015. Subjects with lung disease or anemia were excluded. Obstructive pulmonary impairment was defined as <70% of the predicted value of forced expiratory volume in 1 second/forced vital capacity. Subjects were classified into the early (≤30 minutes) and late (>30 minutes) groups based on the time to first cigarette. Logistic regression and linear regression analyses were used for data analysis.

Results

Ninety-eight subjects (25%) were classified into the early group. After adjusting for smoking behaviors (cigarettes per day and smoking duration), socioeconomic status (education and income), age, and physical activity, an early time to first cigarette was found to be associated with an increased risk of obstructive pulmonary impairment measured using spirometry (adjusted odds ratio, 2.84; 95% confidence interval, 1.22–6.61).

Conclusion

Compared to current smokers with a late time to first cigarette, those with an early time to first cigarette had a higher risk of obstructive pulmonary impairment, especially chronic obstructive pulmonary disease. Classifying smoking-related behaviors, especially time to first cigarette, may help target clinical screening for chronic obstructive pulmonary disease.

The Effects of Ramadan Intermittent Fasting (RIF) on Spirometric Data of Stable COPD Patients: A Pilot Study

No previous study has raised the effects of RIF on lung function data of chronic obstructive pulmonary disease (COPD) patients. The objective of the present study was to assess the effects of RIF on spirometric data measured in male patients with a stable COPD. Sixteen patients with stable COPD (mean ± SD of age: 64 ± 7 years) who fasted during Ramadan volunteered to the study. Three sessions (Before-R, End-R, and After-R) were selected for spirometry tests that were consistently performed 2.5-4.5 hr before fasting break. Assessment sessions comprised: forced vital capacity (FVC), 1st s forced expiratory volume (FEV₁), FEV₁/FVC, peak expiratory flow (PEF), maximal mid-expiratory flow (MMEF), and forced expiratory flow rate at the x% of FVC to be exhaled (FEFx%). A reversibility test was performed only during the Before-Ramadan session. Spirometric data were expressed in percentages of local reference values. Findings were analyzed by applying repeated measures analysis of variance. The mean ± SD of the postbronchodilator FEV₁/FVC ratio and the FEV₁ were, respectively, 0.52 ± 0.14 and 48 ± 19%. The mean ± SD of FEV₁ (Before-R: 47 ± 19, End-R: 45 ± 18, After-R: 44 ± 19%), FVC (Before-R: 73 ± 18, End-R: 71 ± 16, After-R: 69 ± 17%), FEV₁/FVC (Before-R: 67 ± 16, End-R: 66 ± 16, After-R: 65 ± 16%), PEF (Before-R: 46 ± 19, End-R: 47 ± 22, After-R: 45 ± 21%), MMEF (Before-R: 19 ± 10, End-R: 18 ± 8, After-R: 18 ± 9%), FEF_25% (Before-R: 16 ± 6, End-R: 16 ± 5, After-R: 15 ± 5%), FEF_50% (Before-R: 21 ± 14, End-R: 20 ± 12, After-R: 20 ± 12%) and FEF_75% (Before-R: 27 ± 19, End-R: 27 ± 19, After-R: 27 ± 19%) were not significantly influenced by RIF. RIF did not bring about any significant changes in the spirometric data of stable COPD male patients fasting the 2016 holy month of Ramadan.

Estimated effects of air pollution and space-time-activity on cardiopulmonary outcomes in healthy adults: A repeated measures study

BACKGROUND

Exposure to air pollution is known to affect both short and long-term outcomes of the cardiopulmonary system; however, findings on short-term outcomes have been inconsistent and often from isolated and long-term rather than coexisting and short-term exposures, and among susceptible/unhealthy rather than healthy populations.

AIMS

We aimed to investigate separately the annual, daily and daily space-time-activity-weighted effect of ambient air pollution, as well as confounding or modification by other environmental (including noise) or space-time-activity (including total daily physical activity) exposures, on cardiopulmonary outcomes in healthy adults.

METHODS

Participants (N=57: 54% female) had indicators of cardiopulmonary outcomes [blood pressure (BP), pulse (HR) and heart rate variability (HRV {SDNN}), and lung function (spirometry {FEV₁, FVC, SUM})] measured on four different mornings (at least five days apart) in a clinical setting between 2011 and 2014. Spatiotemporal ESCAPE-LUR models were used to estimate daily and annual air pollution exposures (including PM₁₀, PM_Coarse, but not Ozone {derived from closest station}) at participant residential and occupational addresses. Participants' time-activity diaries indicated time spent at either address to allow daily space-time-activity-weighted estimates, and capture total daily physical activity (total-PA {as metabolic-equivalents-of-task, METs}), in the three days preceding health measurements. Multivariate-adjusted linear mixed-effects models (using either annual or daily estimates) were adjusted for possible environmental confounders or mediators including levels of ambient noise and greenness. Causal mediation analysis was also performed separately considering these factors as well as total-PA. All presented models are controlled by age, height, sex and season.

RESULTS

An increase in 5μg/m³ of daily space-time-activity-weighted PM_Coarse exposure was statistically significantly associated with a 4.1% reduction in total heart rate variability (SDNN; p=0.01), and remained robust after adjusting for suspected confounders [except for occupational-address noise (β=-2.7, p=0.20)]. An increase in 10ppb of annual mean Ozone concentration at the residential address was statistically significantly associated with an increase in diastolic BP of 6.4mmHg (p<0.01), which lost statistical significance when substituted with daily space-time-activity-weighted estimates. As for pulmonary function, an increase in 10μg/m³ of annual mean PM₁₀ concentration at the residential address was significantly associated with a 0.3% reduction in FVC (p<0.01) and a 0.5% reduction in SUM (p<0.04), for which again significance was lost when substituted for daily space-time-activity-weighted estimates These associations with pulmonary function remained robust after adjusting for suspected confounders, including annual Ozone, as well as total-PA and bioaerosol (pollen and fungal spore) levels (but not residential-neighborhood greenness {β=-0.22, p=0.09; β=-0.34, p=0.15, respectively}). Multilevel mediation analysis indicated that the proportion mediated as a direct effect on cardiopulmonary outcomes by suspected confounders (including total-PA, residential-neighborhood greenness, and occupational-address noise level) from primary exposures (including PM₁₀, PM_Coarse, and O₃) was not statistically significant.

CONCLUSION

Our findings suggest that increased daily space-time-activity-weighted PM_Coarse exposure levels significantly adversely affect cardiac autonomic modulation (as reduced total HRV) among healthy adults. Additionally, increased annual levels at the residential address of Ozone and PM₁₀ significantly increase diastolic blood pressure and reduce lung function, respectively, among healthy adults. These associations typically remained robust when adjusting for suspected confounders. Occupational-address noise and residential-neighborhood greenness levels, however, were seen as mediators of cardiovascular and pulmonary outcomes, respectively. Total daily physical activity was not seen as a mediator of any of the studied outcomes, which supports the promotion of active mobility within cities.

Does physical fitness enhance lung function in children and young adults?

Although physical activity is important for lung health, it is unclear whether physical fitness influences lung function. We investigated associations between lung function and fitness in two population-based cohort studies of children and young adults.Aerobic fitness was measured using a maximal cycle ergometer test at ages 9, 15, 21 and 29 years in Odense, Denmark and using a submaximal cycle test at ages 15, 26, 32 and 38 years in Dunedin, New Zealand.Aerobic fitness was positively associated with forced expiratory volume in 1 s (FEV₁) and forced vital capacity (FVC) in cross-sectional analyses at all ages in both cohorts, independently of height, weight, sex, asthma and smoking. Each standard deviation difference in fitness was associated with 2-3% predicted higher values of FEV₁ and FVC. Improvements in fitness during childhood and adolescence were associated with growth in lung volumes in longitudinal analyses. These associations tended to be stronger in males than females. No longitudinal associations were found after peak adult lung function had been attained. Fitness was not significantly associated with FEV₁/FVC ratios.Aerobic fitness is positively associated with lung volumes. Improving fitness during childhood and adolescence is associated with greater adult lung volumes, but not with airway calibre.

Leisure-time vigorous physical activity is associated with better lung function: the prospective ECRHS study

OBJECTIVE

We assessed associations between physical activity and lung function, and its decline, in the prospective population-based European Community Respiratory Health Survey cohort.

METHODS

FEV₁ and FVC were measured in 3912 participants at 27-57 years and 39-67 years (mean time between examinations=11.1 years). Physical activity frequency and duration were assessed using questionnaires and used to identify active individuals (physical activity ≥2 times and ≥1 hour per week) at each examination. Adjusted mixed linear regression models assessed associations of regular physical activity with FEV₁ and FVC.

RESULTS

Physical activity frequency and duration increased over the study period. In adjusted models, active individuals at the first examination had higher FEV₁ (43.6 mL (95% CI 12.0 to 75.1)) and FVC (53.9 mL (95% CI 17.8 to 89.9)) at both examinations than their non-active counterparts. These associations appeared restricted to current smokers. In the whole population, FEV₁ and FVC were higher among those who changed from inactive to active during the follow-up (38.0 mL (95% CI 15.8 to 60.3) and 54.2 mL (95% CI 25.1 to 83.3), respectively) and who were consistently active, compared with those consistently non-active. No associations were found for lung function decline.

CONCLUSION

Leisure-time vigorous physical activity was associated with higher FEV₁ and FVC over a 10-year period among current smokers, but not with FEV₁ and FVC decline.

The association between leisure-time physical activity and lung function in older adults: The English longitudinal study of ageing

The longitudinal association between physical activity and lung function is unclear. Therefore, we examined said association over eight years. This study included data from 2966 participants in English Longitudinal Study of Ageing (63±7years [mean±SD]), a prospective study of initially healthy, community dwelling adults. Physical activity was assessed using an interview and lung function using a spirometer at baseline (2004-5) and follow-up (2012-13). General linear regression was used to assess associations between activity and lung function. Logistic regression was used to assess the odds of new cases of abnormal lung function. Some 14% of participants were defined as physically inactive at baseline, 50% were classified into the moderate group, and 36% into the vigorous group. In comparison with remaining inactive at follow-up, remaining active was positively associated with forced vital capacity (FVC) (β=0.09, 95% confidence interval [CI]: 0.01, 0.17; p=0.02) and forced expiratory volume in one second (FEV-1) (β=0.09, 95% CI: 0.02, 0.15; p=0.01) after adjustment for baseline lung function score and other covariates. Using the fifth centile to define the lower limit of normal (that is, -1.64 z scores), there were lower odds of incident abnormal lung function in participants who remained physically active compared to those who remained inactive (FVC odds ratio=0.31, 95% CI: 0.17, 0.55. FEV-1 odds ratio=0.43, 95% CI: 0.26, 0.72). Similar associations were observed in those who became active. This study suggests that remaining physically active or becoming active in older age is positively associated with lung function and reduced odds of abnormal lung function.

The training type influence on male elite athletes' ventilatory function

Background/aim

To assess and compare measured ventilatory volumes (forced expiratory volume in 1 s (FEV₁), peak expirium flow (PEF) and maximal voluntary ventilation (MVV)), ventilatory function capacities (forced vital capacity (FVC) and vital capacity (VC)) and FEV₁/VC ratio in a sample of power and endurance elite athletes and their age-matched and sex-matched sedentary control group.

Methods

A cross-sectional study was applied on male elite athletes (n=470) who were classified according to the type of the predominantly performed exercise in the following way: group 1: endurance group (EG=270), group 2: power athletes group (SG=200) and group 3: sedentary control group (CG=100). The lung VC, FVC, FEV₁, FEV₁/FVC ratio, PEF and MVV were measured in all of the observed subjects, who were also classified with regard to body mass index (BMI) and the percentage of the body fat (BF%).

Results

The CG had the highest BF% value, while the endurance group had the lowest BMI and BF% value, which is significantly different from the other two groups (p<0.05). The observed values of VC, FVC and FEV₁ in the EG were significantly higher than those from the other two groups (p<0.05). There were no differences concerning the observed FEV₁/FVC ratio.

Conclusions

A continued endurance physical activity leads to adaptive changes in spirometric parameters (VC, FVC and FEV₁), highlighting the fact that there is a need for specific consideration of different respiratory ‘pattern’ development in different types of sport, which also has to be further evaluated.

The Effects of Ramadan Fasting on the Spirometric Data of Healthy Adult Males

The few studies carried out on the effects of Ramadan fasting (RF) on spirometric values present contradictory conclusions. This study aimed at assessing whether RF affects healthy adults' spirometric values. Twenty-nine nonsmoking healthy males ( M ± standard error of mean [ SEM] of age: 27 ± 1 years) who fasted during Ramadan (June 29-July 28, 2014) volunteered to the study. Three periods (before-Ramadan [June 23-25], mid-Ramadan [July 14-16] and after-Ramadan [August 11-14]) were selected for spirometry measurements that were consistently performed 5.5 to 3.5 hours (between 15:00 and 17:00 hours) before fasting break. Assessment sessions comprised following: weight (kg), forced vital capacity (FVC), first second expiratory volume (FEV₁), FEV₁/FVC, peak expiratory flow (PEF), maximal mid expiratory flow (MMEF), and forced expiratory flow rate at the x% of FVC to be exhaled (FEF _x%). Spirometric data were expressed in percentages of reference values. Results were analyzed by applying repeated measures analysis of variance. The M ± SEM of weight (before-R: 81.6 ± 2.8 kg, mid-R: 80.8 ± 2.9 kg, after-R: 81.2 ± 2.9 kg), FEV₁ (before-R: 99 ± 2%, mid-R: 98 ± 2%, after-R: 98 ± 2%), FVC (before-R: 103 ± 2%, mid-R: 101 ± 2%, after-R: 101 ± 2%), PEF (before-R: 112 ± 3%, mid-R: 113 ± 2%, after-R: 114 ± 3%), MMEF (before-R: 83 ± 3%, mid-R: 83 ± 3%, after-R: 82 ± 3%), FEF_25% (before-R: 90 ± 5%, mid-R: 89 ± 6%, after-R: 87 ± 6%), FEF_50% (before-R: 94 ± 4%, mid-R: 91 ± 4%, after-R: 93 ± 3%), and FEF_75% (before-R: 108 ± 3%, mid-R: 111 ± 2%, after-R:111 ± 3%) were not significantly influenced by RF. To conclude, RF did not bring about any significant changes in the spirometric values of nonsmoking healthy adult males.