Cardiorespiratory Outcomes Research Articles

In people with stroke, how does cardiorespiratory training affect outcomes?

In people with stroke, how does cardiorespiratory training affect outcomes?

Interdisciplinary Weight Loss and Lifestyle Intervention for Obstructive Sleep Apnoea in Adults: Rationale, Design and Methodology of the INTERAPNEA Study.

Obesity is a major risk factor for obstructive sleep apnoea (OSA), the most common sleep-disordered breathing related to neurocognitive and metabolic syndromes, type II diabetes, and cardiovascular diseases. Although strongly recommended for this condition, there are no studies on the effectiveness of an interdisciplinary weight loss and lifestyle intervention including nutrition, exercise, sleep hygiene, and smoking and alcohol cessation. INTERAPNEA is a randomised controlled trial with a two-arm parallel design aimed at determining the effects of an interdisciplinary tailored weight loss and lifestyle intervention on OSA outcomes. The study will include 84 males aged 18–65 with a body mass index of ≥25 kg/m2 and severe to moderate OSA randomly assigned to usual care (i.e., continuous positive airway pressure), or interdisciplinary weight loss and lifestyle intervention combined with usual care. Outcomes will be measured at baseline, intervention end-point, and six-month post-intervention, including apnoea-hypopnoea index (primary outcome), other neurophysical and cardiorespiratory polysomnographic outcomes, sleep quality, daily functioning and mood, body weight and composition, physical fitness, blood biomarkers, health-related quality of life, and cost-effectiveness. INTERAPNEA may serve to establish a cost-effective treatment not only for the improvement of OSA and its vast and severe comorbidities, but also for a potential remission of this condition.

Associations of wildfire smoke PM2.5 exposure with cardiorespiratory events in Colorado 2011–2014

BackgroundSubstantial increases in wildfire activity have been recorded in recent decades. Wildfires influence the chemical composition and concentration of particulate matter ≤2.5 μm in aerodynamic diameter (PM2.5). However, relatively few epidemiologic studies focus on the health impacts of wildfire smoke PM2.5 compared with the number of studies focusing on total PM2.5 exposure. ObjectivesWe estimated the associations between cardiorespiratory acute events and exposure to smoke PM2.5 in Colorado using a novel exposure model to separate smoke PM2.5 from background ambient PM2.5 levels. MethodsWe obtained emergency department visits and hospitalizations for acute cardiorespiratory outcomes from Colorado for May–August 2011–2014, geocoded to a 4 km geographic grid. Combining ground measurements, chemical transport models, and remote sensing data, we estimated smoke PM2.5 and non-smoke PM2.5 on a 1 km spatial grid and aggregated to match the resolution of the health data. Time-stratified, case-crossover models were fit using conditional logistic regression to estimate associations between fire smoke PM2.5 and non-smoke PM2.5 for overall and age-stratified outcomes using 2-day averaging windows for cardiovascular disease and 3-day windows for respiratory disease. ResultsPer 1 μg/m3 increase in fire smoke PM2.5, statistically significant associations were observed for asthma (OR = 1.081 (1.058, 1.105)) and combined respiratory disease (OR = 1.021 (1.012, 1.031)). No significant relationships were evident for cardiovascular diseases and smoke PM2.5. Associations with non-smoke PM2.5 were null for all outcomes. Positive age-specific associations related to smoke PM2.5 were observed for asthma and combined respiratory disease in children, and for asthma, bronchitis, COPD, and combined respiratory disease in adults. No significant associations were found in older adults. DiscussionThis is the first multi-year, high-resolution epidemiologic study to incorporate statistical and chemical transport modeling methods to estimate PM2.5 exposure due to wildfires. Our results allow for a more precise assessment of the population health impact of wildfire-related PM2.5 exposure in a changing climate.

Heart Rate Variability and Cardiorespiratory Fitness in Non-Hispanic Black Versus Non-Hispanic White Adolescents With Type 1 Diabetes.

Evidence indicates that fewer non-Hispanic black versus non-Hispanic white youths with type 1 diabetes are meeting treatment goals for optimal glycemic outcomes, predisposing them to risks for cardiovascular (CV) morbidity and mortality in adulthood. We sought to assess the association of sex and race with heart rate variability (HRV) and cardiorespiratory fitness in adolescents with type 1 diabetes. The association between the HRV and cardiorespiratory outcomes with glucose control was also examined. A secondary data analysis of 95 adolescents with type 1 diabetes (n = 66 non-Hispanic white n = 29 non-Hispanic black) was used. Using 24-hour Holter recordings, spectral and time domain measures of HRV were obtained. Cardiorespiratory fitness using a graded exercise test was completed. Descriptive statistics and Pearson correlation coefficients were used to assess associations between glucose control and study outcomes, and general linear models were applied to explore and quantify associations of sex and race with HRV and cardiorespiratory fitness. Body mass index (mean [standard deviation]) was similar between non-Hispanic black (23.5 [3.9]) and non-Hispanic white (22.7 [3.8]) adolescents. Females and non-Hispanic black adolescents had significantly lower HRV and cardiorespiratory fitness levels. Moderate associations were found between lower HRV and poorer glycemic control (HbA1c). Recent HbA1c was significantly higher in non-Hispanic black (9.7 [1.8]) than non-Hispanic white (8.2 [1.2]). Findings support the importance of early identification of CV health risks in adolescents with type 1 diabetes, particularly for non-Hispanic black adolescents. Interventions focused on overall improvement in glycemic control for adolescents with type 1 diabetes are a priority for minimizing future CV complications.

Health Effects of Household Solid Fuel Use: Findings from 11 Countries within the Prospective Urban and Rural Epidemiology Study.

Background:Household air pollution (HAP) from solid fuel use for cooking affects 2.5 billion individuals globally and may contribute substantially to disease burden. However, few prospective studies have assessed the impact of HAP on mortality and cardiorespiratory disease.Objectives:Our goal was to evaluate associations between HAP and mortality, cardiovascular disease (CVD), and respiratory disease in the prospective urban and rural epidemiology (PURE) study.Methods:We studied 91,350 adults 35–70 y of age from 467 urban and rural communities in 11 countries (Bangladesh, Brazil, Chile, China, Colombia, India, Pakistan, Philippines, South Africa, Tanzania, and Zimbabwe). After a median follow-up period of 9.1 y, we recorded 6,595 deaths, 5,472 incident cases of CVD (CVD death or nonfatal myocardial infarction, stroke, or heart failure), and 2,436 incident cases of respiratory disease (respiratory death or nonfatal chronic obstructive pulmonary disease, pulmonary tuberculosis, pneumonia, or lung cancer). We used Cox proportional hazards models adjusted for individual, household, and community-level characteristics to compare events for individuals living in households that used solid fuels for cooking to those using electricity or gas.Results:We found that 41.8% of participants lived in households using solid fuels as their primary cooking fuel. Compared with electricity or gas, solid fuel use was associated with fully adjusted hazard ratios of 1.12 (95% CI: 1.04, 1.21) for all-cause mortality, 1.08 (95% CI: 0.99, 1.17) for fatal or nonfatal CVD, 1.14 (95% CI: 1.00, 1.30) for fatal or nonfatal respiratory disease, and 1.12 (95% CI: 1.06, 1.19) for mortality from any cause or the first incidence of a nonfatal cardiorespiratory outcome. Associations persisted in extensive sensitivity analyses, but small differences were observed across study regions and across individual and household characteristics.Discussion:Use of solid fuels for cooking is a risk factor for mortality and cardiorespiratory disease. Continued efforts to replace solid fuels with cleaner alternatives are needed to reduce premature mortality and morbidity in developing countries. https://doi.org/10.1289/EHP3915

The acute effects of whole blood donation on cardiorespiratory and haematological factors in exercise: A systematic review.

BackgroundThis systematic review aimed to collect the relevant historical and current literature to produce an informed analysis of the acute effects on cardiorespiratory and haematological factors following whole blood donation (~ 470 ml) during exercise. Testing the hypothesises that blood donation produces either no changes (Null) or produces significant changes (alternate) in haematology, , heart rate, exercising power and time.MethodsFour databases of medical and science orientations were searched with terms sensitive to connections regarding exercise, blood donation (400–500 ml)/haematology, , heart rate, exercising power and time. The study retrieval process utilised the PRISMA approach and selection was via an adapted scoring method according to the Consensus based Standards for the selection of health Measurements Instruments (COSMIN). Systematic review focused on 24–48 hrs post donation. Details of the PRSIMA checklist can be found in the accompanying online document.ResultsFollowing scrutiny of 48 research papers by two independent assessors 8 experimental studies were included. Four studies showed a mean reduction for difference in (- 2.4 ± 1.4 ml∙kg-1∙min-1) and a medium effect size (-0.26). No statistical significance was present at the mean meta-analysis level, also the case for heart rate, time to exhaustion and power. A mean reduction was seen in haemoglobin (- 1.05 g.dL-1), haematocrit (- 3.71%) and red blood cells (- 0.44 Mio μL-1), very large effect size was observed (Cohen’s d, -0.75, -1.16 and -4.23 respectively) and statistical significance (95% CI, -2.04, -0.54; -4.59, 2.28 and -4.37, -4.10 respectively).ConclusionAlthough individual studies show that Is reduced from blood donation pooled results show that is indeed not significantly reduced from blood donation 24–48 hrs post donation. Additionally sub-maximally there isn’t enough data to produce substantial comparatives. Furthermore, this systematic review demonstrates that there are not enough high-quality studies regarding cardiorespiratory outcomes following blood donation.

Review of Acellular Assays of Ambient Particulate Matter Oxidative Potential: Methods and Relationships with Composition, Sources, and Health Effects.

Oxidative stress is a potential mechanism of action for particulate matter (PM) toxicity and can occur when the body's antioxidant capacity cannot counteract or detoxify harmful effects of reactive oxygen species (ROS) due to an excess presence of ROS. ROS are introduced to the body via inhalation of PM with these species present on and/or within the particles (particle-bound ROS) and/or through catalytic generation of ROS in vivo after inhaling redox-active PM species (oxidative potential, OP). The recent development of acellular OP measurement techniques has led to a surge in research across the globe. In this review, particle-bound ROS techniques are discussed briefly while OP measurements are the focus due to an increasing number of epidemiologic studies using OP measurements showing associations with adverse health effects in some studies. The most common OP measurement techniques, including the dithiothreitol assay, glutathione assay, and ascorbic acid assay, are discussed along with evidence for utility of OP measurements in epidemiologic studies and PM characteristics that drive different responses between assay types (such as species composition, emission source, and photochemistry). Overall, most OP assays respond to metals like copper than can be found in emission sources like vehicles. Some OP assays respond to organics, especially photochemically aged organics, from sources like biomass burning. Select OP measurements have significant associations with certain cardiorespiratory end points, such as asthma, congestive heart disease, and lung cancer. In fact, multiple studies have found that exposure to OP measured using the dithiothreitol and glutathione assays drives higher risk ratios for certain cardiorespiratory outcomes than PM mass, suggesting OP measurements may be integrating the health-relevant fraction of PM and will be useful tools for future health analyses. The compositional impacts, including species and emission sources, on OP could have serious implications for health-relevant PM exposure. Though more work is needed, OP assays show promise for health studies as they integrate the impacts of PM species and properties on catalytic redox reactions into one measurement, and current work highlights the importance of metals, organic carbon, vehicles, and biomass burning emissions to PM exposures that could impact health.

Anandamide Is Related to Clinical and Cardiorespiratory Benefits of Aerobic Exercise Training in Migraine Patients: A Randomized Controlled Clinical Trial.

Introduction: Since endocannabinoids have been implicated in migraine pathophysiology, we conducted a randomized, controlled clinical trial to test the effects of a 12-week aerobic exercise intervention on plasma anandamide (AEA) and its relation with clinical, psychological, and cardiorespiratory outcomes. Materials and Methods: Episodic migraine patients taking no preventive drugs and nonheadache individuals were recruited from Hospital São Paulo and a tertiary headache clinic between March 2012 and March 2015. Participants were randomly assigned to receive aerobic exercise or enter the waitlist. Primary outcome was changes in plasma AEA; secondary outcome was number of days with migraine/month; and other clinical variables, mood scores, and cardiorespiratory fitness were chosen as tertiary outcomes. Measurements were taken on headache-free days. Data were analyzed by generalized linear models. Discussion: Fifty participants concluded the study (mean±SD age=36.2±10.9, and BMI=26.5±4.5). The plasma AEA reduced in migraine exercise (p<0.05) and control exercise groups (p<0.01). The number of days with migraine (p<0.01), migraine attacks (p<0.05), and abortive medication used (p<0.05) reduced in the migraine exercise group, whereas cardiorespiratory fitness increased in migraine exercise and control exercise groups (both p<0.05). Anxiety, depression, anger, and fatigue scores improved in the migraine exercise group (p<0.05 for all). Significant correlations between reduction in abortive medication used and cardiorespiratory fitness (r=-0.81 p<0.001), and reduced AEA (r=0.68 p<0.05) were found. Conclusions: This study suggests that peripheral AEA metabolism may be partly linked to the clinical and cardiorespiratory benefits of regular aerobic exercise in migraine patients. Trials registration: #NCT01972607.

Exercise, or exercise and diet for the management of polycystic ovary syndrome: a systematic review and meta-analysis

BackgroundTypically, management of PCOS focuses on lifestyle changes (exercise and diet), aiming to alleviate symptoms, and lower the associated risk of type 2 diabetes and cardiovascular disease. Our objective was to analyse evidence on the effectiveness of exercise in the management of PCOS, when compared to (i) usual care, (ii) diet alone, and (iii) exercise combined with diet, and also exercise combined with diet, compared to (i) control or usual care and (ii) diet alone.MethodsRelevant databases were searched (June 2017) with no time limit for trial inclusion. Eligible trials employed a randomised or quasi-randomised design to measure the chronic effects of exercise, or exercise and diet in women with PCOS.ResultsSearches returned 2390 articles; of those, 27 papers from 18 trials were included. Results are presented as mean difference (MD) and 95% confidence intervals (95% CI). Compared with control, exercise had a statistical effect on change from baseline fasting insulin (MD − 2.44 μIU/mL, 95% CIs − 4.24 to − 0.64; very low-quality evidence), HOMA-IR (− 0.57, − 0.99 to − 0.14; very low-quality evidence), total cholesterol (− 5.88 mg/dL, − 9.92 to − 1.83; low-quality evidence), LDL cholesterol (− 7.39 mg/dL, − 9.83 to − 4.95; low-quality evidence), and triglycerides (− 4.78 mg/dL, − 7.52 to − 2.05; low-quality evidence). Exercise also improved VO2 max (3.84 ml/kg/min, 2.87 to 4.81), waist circumference (− 2.62 cm, − 4.13 to − 1.11), and body fat percentage (− 1.39%, − 2.61 to − 0.18) when compared with usual care. No effect was found for change value systolic/diastolic blood pressure, fasting glucose, HDL cholesterol (all low-quality evidence), or waist-to-hip ratio. Many favourable change score findings were supported by post-intervention value analyses: fasting insulin (− 2.11 μIU/mL, − 3.49 to − 0.73), total cholesterol (− 6.66 mg/dL, − 11.14 to − 2.17), LDL cholesterol (− 6.91 mg/dL, − 12.02 to − 1.80), and VO2 max (5.01 ml/kg/min, 3.48 to 6.54). Statistically lower BMI (− 1.02 kg/m2, − 1.81 to − 0.23) and resting heart rate (− 3.26 beats/min − 4.93 to − 1.59) were also revealed in post-intervention analysis. Subgroup analyses revealed the greatest improvements in overweight/obese participants, and more outcomes improved when interventions were supervised, aerobic in nature, or of a shorter duration. Based on limited data, we found no differences for any outcome between the effects of exercise and diet combined, and diet alone. It was not possible to compare exercise vs diet or exercise and diet combined vs diet.ConclusionStatistically beneficial effects of exercise were found for a range of metabolic, anthropometric, and cardiorespiratory fitness-related outcomes. However, caution should be adopted when interpreting these findings since many outcomes present modest effects and wide CIs, and statistical effects in many analyses are sensitive to the addition/removal of individual trials. Future work should focus on rigorously designed, well-reported trials that make comparisons involving both exercise and diet.Systematic review registrationThis systematic review was prospectively registered on the Prospero International Prospective Register of Systematic Reviews (CRD42017062576)

«We do not stop exercising because we grow old – we grow old because we stop exercising.» Dr Kenneth Cooper – Editorial 4/2019

In 1968, Air Force Colonel Cooper wrote his first bestselling book, Aerobics, and sparked a fitness revolution. The general public got an idea of the multiple benefits of physical activity and exercise to improve or recover health and function. He developed his knowledge and training principles in the military, aiming to help soldiers stay fit and healthy. This led to the development of a fitness test most of us remember only too well: the 12-minute Cooper test. In 1970, retiring from the military, he founded the Cooper Aerobics Center in Dallas, which has hosted an Institute responsible for much of the research we have on the relationship between cardiorespiratory fitness and health outcomes, through the Aerobics Center Longitudinal Studies. These were pursued under the leadership of Pr Steven Blair [1] and became the largest ongoing observational study on fitness and health, with countless publications on more than 112’000 subjects.

Associations between multipollutant day types and select cardiorespiratory outcomes in Columbia, South Carolina, 2002 to 2013.

Health studies of air pollution are increasingly aiming to study associations between air pollutant mixtures and health. Estimate associations between observed combinations of ambient air pollutants and select cardiorespiratory outcomes in Columbia, SC during 2002 to 2013. We estimate associations using a two-stage approach. First, we identified a collection of observed pollutant combinations, which we define as multipollutant day types (MDTs), by applying a self-organizing map (SOM) to daily measures of nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and particulate matter ≤ 2.5 microns (PM2.5). Then, overdispersed Poisson time-series models were used to estimate associations between MDTs and each outcome using a 'clean' MDT referent and controlling for long-term, seasonal, and day-of-the-week trends and meteorology. Outcomes included daily emergency department visits for asthma and upper respiratory infection (URI), and hospital admissions for congestive heart failure (CHF) and ischemic heart disease (IHD). We found that a number of MDTs were significantly and positively associated (point estimates ranged from~2-5%) with cardiorespiratory outcomes in Columbia when compared to days with low pollution. Estimated associations revealed that outcomes for asthma, URIs, and IHD increased 2-4% on warm, dry days experiencing elevated levels of O3 and PM2.5. We also found that cooler days with higher NO2 pollution associated with increased asthma, CHF, and IHD outcomes (2-5%). Our analysis continues support for using self-organizing maps to develop multipollutant exposure metrics and further illustrates how such metrics can be applied to explore associations between pertinent pollutant combinations and health.

Abstract 16590: The Association Between Long-Term Changes in Cardiorespiratory Fitness and Mortality Risk

Introduction: There is a strong inverse association between cardiorespiratory fitness (CRF) and mortality outcomes. This relationship has predominantly been assessed cross-sectionally, however low CRF is a modifiable risk factor, thus assessing this association using a single baseline measure may be sub-optimal. The primary purpose of this research was to examine the association of the long-term change in CRF, measured using cardiopulmonary exercise testing (CPX) with all-cause and disease-specific mortality. Methods: Participants included 833 apparently healthy men and women (42.9±10.8 y) who underwent two maximal CPXs, the second CPX being ≥ 1 year following the baseline assessment. Participants were followed for 17.7 ± 11.8 years for all-cause, cardiovascular disease (CVD), and cancer mortality. Cox-proportional hazard models were performed to determine the association between the change in CRF, computed as visit 1 (V1) peak oxygen consumption (VO 2peak (ml·kg -1· min -1 )) - visit 2 (V2) VO 2peak , and mortality outcomes. Results: During follow-up, 172 participants died. Overall, the change in CPX-derived CRF was inversely related to all-cause, CVD, and cancer mortality (p&lt;0.05). Each 1 ml·kg -1· min -1 increase was associated with a 10.8, 14.7, and 15.9% reductions in all-cause, CVD, and cancer mortality, respectively. The inverse relationship between CRF and all-cause mortality remained significant (p&lt;0.05) when men and women were examined independently, after adjusting for years since first CPX, baseline VO 2peak , and age. Conclusions: Long-term changes in CRF were inversely related to mortality outcomes, and mortality was better predicted by CRF measured at subsequent examination than baseline CRF. These findings support the recent American Heart Association scientific statement advocating CRF as a clinical vital sign that should be assessed routinely in clinical practice, as well as support regular participation in physical activity to maintain adequate CRF levels across the lifespan.

A Fixed Effect Analysis of the Variation of Socioeconomic and Environmental Factors and Rate of Asthma Onset in Children Overtime within Regions of Qu&amp;#233;bec (Canada)

Socioeconomic conditions and exposure to air pollutants have been related to cardiorespiratory outcomes. Nonetheless, very few studies have looked at how changes in environmental and socioeconomic conditions overtime relate to changes in health outcomes.We assessed the relationships between the changes in environmental and socioeconomic conditions and change in asthma onset in children &amp;lt;13 years within small geographic units of Qu&amp;#233;bec (i.e. census tracts or local health regions called CLSC) using an ecological longitudinal design. We used univariate and multivariate fixed effects negative binomial models with the population of children aged 0-14 years per geographical area as an offset to assess associations. New cases of asthma were identified from linked medico-administrative databases using a validated algorithm. For the 1386 areas, we computed for the years 2002 to 2011, the median income from the Census, the average regional background of fine particulate levels (PM2.5) estimated with ground and satellite information, the reported industrial air pollutant emissions of PM2.5 and sulfur dioxide (SO2). We also used environmental tobacco smoke (ETS) information from the Canadian CCHS survey for 18 health regions to estimate exposure of children to environmental tobacco smoke (ETS) for the years 2002 to 2011.From a multivariate model, there was a 4.21% increase in the rate of asthma onset per change of 1 ug/m3 of regional PM2.5 levels (95%CI: 3.3-5.0), and 2.88% increase per change of 1 percent of ETS (95%CI: 2.6-3.1) within studied areas. In this model, median income and industrial emissions were not significantly related to the rate of asthma onset. Our findings suggest that small area changes in regional PM2.5 levels and in ETS, which have both decreased over the years, are associated with improvements in asthma outcomes in Qu&amp;#233;bec.

Spatiotemporal Modeling of Oxidative Potential of Ambient Particulate Matter Using Chemical Transport Model-Derived Emission Sources

Multiple epidemiologic studies have found associations between the oxidative potential (OP) of fine particulate matter (PM2.5) and adverse cardiorespiratory outcomes, supporting the hypothesis that PM may be capable of inducing oxidative stress. However, limited observational data on OP restrict the scope of exposure and epidemiologic analyses. Here, an advanced PM2.5 emission source impact analysis is used with limited OP observations to develop and apply a model capable of simulating daily OP over a wide spatial domain, specifically across the eastern United States. OP of ambient water-soluble PM2.5 was measured using an accellular dithiothreitol (DTT) assay at four locations across the southeastern United States from June 2012-July 2013. PM2.5 source apportionment was performed during the same time period across the eastern United States using CMAQ-DDM with advanced data assimilation techniques to minimize biases. These sources were related to ambient OP measurements using multivariate linear regression with backward selection. The resulting model was applied to estimate spatio-temporal trends in ambient OP across the eastern United States. Regression analyses show that vehicles and fires significantly contribute to OP, supporting previous findings. Higher OP is generally seen in the winter than the summer and in urban areas compared to rural areas. The intraurban spatial distribution driven by vehicle impacts was briefly investigated, showing a high spatial correlation with RLINE modeled primary roadway concentrations. The CMAQ-DDM modeling approach may be useful for health studies utilizing exposure data across a large study domain (e.g. multiple cities), can integrate a broad range of OP measurements, and can help to identify sources of PM with high OP for regulatory purposes. While this work was supported in part by a grant from the US EPA, this abstract does not necessarily reflect EPA policy.

Water-based aerobic training improves strength parameters and cardiorespiratory outcomes in elderly women.

The aim of the present study was to compare the effects of water-based aerobic training and water-based resistance training on muscular strength and cardiorespiratory fitness in older women. Sixty-nine individuals were randomized into the following three groups: the water-based aerobic training (WA, n = 23) group, the water-based resistance training (WR, n = 23) group, and the control group (CG, n = 23). Participants were trained two times per week for 10 weeks. The trainings presented a linear periodization with an increase in the volume-intensity relation. Maximal dynamic muscular strength and the cardiorespiratory fitness were evaluated before the start of training and after 10 weeks of training. Only the WA group showed an increase in maximal oxygen consumption (13.8%) and oxygen consumption at the second ventilatory threshold (16.4%). Maximal dynamic strength of knee extensors improved in 10.6% of WA, 8.0% of WR, and 4.7% of CG participants, without any difference between the groups. Maximal dynamic strength of knee flexors was increased in 14.1% of WA and in 17.7% of WR participants; however, it remains unchanged in CG participants. No differences were observed in resting heart rate, peak heart rate, heart rate at the second ventilatory threshold and maximal dynamic strength of shoulder horizontal flexors. It was concluded that WA seems to be more efficient for improvement in cardiorespiratory responses, and both WA and WR were efficient for development of maximal dynamic strength of knee flexion and extension.

The effects of two different doses of ultraviolet-A light exposure on nitric oxide metabolites and cardiorespiratory outcomes

PurposeThe present study investigated different doses of ultraviolet-A (UV-A) light on plasma nitric oxide metabolites and cardiorespiratory variables.MethodsTen healthy male participants completed three experimental conditions, 7 days apart. Participants were exposed to no light (CON); 10 J cm2 (15 min) of UV-A light (UVA10) and 20 J cm2 (30 min) of UV-A light (UVA20) in a randomized order. Plasma nitrite [NO2−] and nitrate [NO3−] concentrations, blood pressure (BP), and heart rate (HR) were recorded before, immediately after exposure and 30 min post-exposure. Whole body oxygen utilization ({{dot{V}}}{rm O}_{2}), resting metabolic rate (RMR) and skin temperature were recorded continuously.ResultsNone of the measured parameters changed significantly during CON (all P > 0.05). {{dot{V}}}{rm O}_{2} and RMR were significantly reduced immediately after UVA10 (P < 0.05) despite no change in plasma [NO2−] (P > 0.05). Immediately after exposure to UVA20, plasma [NO2−] was higher (P = 0.014) and {{dot{V}}}{rm O}_{2} and RMR tended to be lower compared to baseline (P = 0.06). There were no differences in [NO2−] or {{dot{V}}}{rm O}_{2} at the 30 min time point in any condition. UV-A exposure did not alter systolic BP, diastolic BP or MAP (all P > 0.05). UV-A light did not alter plasma [NO3−] at any time point (all P > 0.05).ConclusionsThis study demonstrates that a UV-A dose of 20 J cm2 is necessary to increase plasma [NO2−] although a smaller dose is capable of reducing {{dot{V}}}{rm O}_{2} and RMR at rest. Exposure to UV-A did not significantly reduce BP in this cohort of healthy adults. These data suggest that exposure to sunlight has a meaningful acute impact on metabolic function.

Cardiorespiratory Fitness and Health Outcomes: A Call to Standardize Fitness Categories

An inverse association between physical activity or fitness status and health outcomes has been reported by several cohort studies. When fitness categories are established in quartiles or quintiles based on the peak exercise capacity achieved, the association is graded. Although significant health benefits of increased cardiorespiratory fitness (CRF) have been uniformly reported, the degree of protection has varied substantially between studies. This variability is likely due to varying methods used to define CRF categories, and not considering age, despite its strong effect on CRF. To ameliorate these methodological discrepancies, we propose standardized guidelines by which age-specific CRF categories should be defined.

Chronic Physiological Effects of Swim Training Interventions in Non-Elite Swimmers: A Systematic Review and Meta-Analysis.

Swimming is a popular and potentially health-enhancing exercise, but has received less scientific attention compared with other exercise modes. The objective of the study was to determine the chronic (long-term) effect of pool swim training on physiological outcomes in non-elite or non-competitive swimming participants. This study was a systematic review with a meta-analysis. We searched the electronic databases PubMed, EMBASE and CENTRAL from inception to March 2017. The eligibility criteria included randomised controlled trials, quasi-randomised controlled trials and controlled trials of chronic (long-term) swimming interventions in non-elite or non-competitive swimming participants, with a physiological outcome measure. Our search of 6712 records revealed 29 eligible studies. Swimming had a significant and clinically meaningful effect on maximal oxygen uptake compared with the control in an analysis including multiple populations (mean difference 6.32mL/kg/min; 95% confidence interval 4.33-8.31), and subgroup analyses of healthy children/adolescents (mean difference 7.93mL/kg/min; 95% confidence interval 3.31-12.55) and those with asthma (mean difference 9.67mL/kg/min; 95% confidence interval 5.84-13.51) and healthy adults (mean difference 5.87mL/kg/min; 95% confidence interval 2.93-8.81). Swimming also resulted in significant improvements in other cardiorespiratory fitness-related outcomes such as maximal minute ventilation (mean difference 0.61 L/min; 95% confidence interval 0.17-1.05), submaximal exercise performance (standardised mean difference 0.64; 95% confidence interval 0.14-1.13) and total exercise test time (mean difference 4.27min; 95% confidence interval 2.11-6.42). Compared with the control, swimming had significant favourable effects on body mass (mean difference -2.90kg, 95% confidence interval -5.02 to -0.78), body fat percentage in multiple populations (mean difference -1.92%; 95% confidence interval -3.25 to -0.60) and healthy children/adolescents (mean difference - 1.92%; 95% confidence interval -4.64 to -0.80) and lean mass (mean difference 1.96kg; 95% confidence interval 0.21-3.71), but negative effects on waist circumference in a pooled analysis of two studies involving adults with hypertension (mean difference 4.03cm; 95% confidence interval 2.58-5.49). Regarding lung function, significant effects of swimming vs. the control were found only for peak expiratory volume in analyses including children/adolescents combined with healthy adults (mean difference 58.74 L/min; 95% confidence interval 29.70-87.78) and children/adolescents with asthma alone (mean difference 63.49 L/min; 95% confidence interval 25.01-101.97). Based on limited data, swimming had similar effects to other exercise modes, except for higher post-intervention body mass index values with swimming vs. running in healthy adults (mean difference 1.18kg/m2; 95% confidence interval 0.54-1.81). Swimming may offer robust beneficial effects on cardiorespiratory fitness and body composition across multiple populations and effects may be comparable to other exercise modes. Future randomised controlled trials are required to establish the effectiveness of swimming on physiological outcomes in healthy populations and those with non-communicable disease.

Mid-childhood outcomes after pre-viable preterm premature rupture of membranes.

Investigate cardiorespiratory outcomes in children surviving previable preterm premature rupture of membranes (PV-PPROM) before 22 weeks' gestational age (GA) with minimum 2 weeks latency. Single institution, follow-up of retrospectively identified children who were born after PV-PPROM during 2000-2004, and individually matched preterm-born controls. Eleven PV-PPROM and matched control children were included at mean age of 10.5 and 10.7 years. Rupture of membranes occurred at mean GA 182 and 276 weeks and birth at 283 and 286 weeks, respectively. Compared to controls, the PV-PPROM group had significantly poorer lung function, findings on echocardiography indicating mild pulmonary hypertension, and lower peak oxygen consumption. Chart reviews suggested more motor difficulties and a tendency towards more problems with learning and attention. The findings highlight a preterm-born sub-group in need of targeted long-term monitoring and possibly interventions regarding future cardiorespiratory and neurodevelopmental function.

Cardiorespiratory responses of air filtration: A randomized crossover intervention trial in seniors living in Beijing: Beijing Indoor Air Purifier StudY, BIAPSY

In this Beijing Indoor Air Purifier StudY (BIAPSY), we conducted a randomized crossover intervention trial in a panel of 35 non-smoking senior participants with free-living, with and without chronic obstructive pulmonary disease (COPD). Portable air filtration units were randomly allocated to active-(filter in) for 2weeks and sham-mode (filter out) for 2weeks in the households. We examined the differences in indoor air pollutant concentrations in 20 study homes and a suite of cardio-respiratory biomarker levels in study participants between filtration modes, with and without adjustment for potential confounders. Following active filtration, we observed significant reductions from 60±45 to 24±15μg/m3 in ten-day averages of indoor PM2.5 and reductions from 3.87±1.65 to 1.81±1.19m−1.10−5 in ten-day averages of indoor BC, compared to sham-mode filtration. The major components of indoor PM2.5, including water soluble organics, NO3−, SO42−, Zn2+, Pb2+ and K+, were also reduced significantly by 42% to 63%. However, following active filtration, we only observed significant reductions on systemic inflammation measured as of IL-8 at 58.59% (95% CI: −76.31, −27.64) in the total group of participants and 70.04% (95% CI: −83.05, −47.05) in the subset of COPD patients, with adjustments. We were not able to detect improvements on lung function, blood pressure, and heart rate variability, following short-term intervention of two-week active air filtration. In conclusion, our results showed that indoor air filtration produced clear improvement on indoor air quality, but no demonstrable changes in the cardio-respiratory outcomes of study interest observed in the seniors living with real-world air pollution exposures.