Determinants Of Cardiorespiratory Fitness Research Articles

Autonomic dysfunction and exercise intolerance in post-COVID-19 - An as yet underestimated organ system?

Individuals recovering from COVID-19 often present with persistent symptoms, particularly exercise intolerance and low cardiorespiratory fitness. Put simply, the Wasserman gear system describes the interdependence of heart, lungs, and musculature as determinants of cardiorespiratory fitness. Based on this system, recent findings indicate a contribution of peripheral, cardiovascular, and lung diffusion limitations to persistent symptoms of exercise intolerance and low cardiorespiratory fitness. The autonomic nervous system as an organ system involved in the pathophysiology of exercise intolerance and low cardiorespiratory fitness, has received only little attention as of yet. Hence, our article discusses contribution of the autonomic nervous system through four potential pathways, namely alterations in (1) cerebral hemodynamics, (2) afferent and efferent signaling, (3) central hypersensitivity, and (4) appraisal and engagement in physical activity. These pathways are summarized in a psycho-pathophysiological model. Consequently, this article encourages a shift in perspective by examining the state of the pulmonary and cardiovascular system, the periphery, and auxiliary, the autonomic nervous system as potential underlying mechanisms for exercise intolerance and low cardiorespiratory fitness in patients with post-COVID-19.

RELATIONSHIP BETWEEN ANTHROPOMETRY AND CARDIORESPIRATORY FITNESS AMONG UiTM FOOTBALL PLAYERS

Cardiorespiratory fitness (CRF) is one of the important components among football players. Physiological characteristics of individuals such as anthropometry may influence the level of CRF. Therefore, this study aims to determine the relationship between anthropometry and CRF among UiTM Football Players. A causal- comparative research design, consisting of 24 male participants representing Universiti Teknologi MARA Football Club (UiTM FC) were recruited. Anthropometry was measured via body weight and body height and CRF was measured using a bleep test and the result of the test was calculated to estimate maximum volume of oxygen (VO2 max). Pearson correlation was used to determine the relationship between anthropometry and CRF. Mean score for anthropometry was 65.17 ± 5.90 for body weight (kg) and 171.18 ± 4.66 for body height (cm). Mean score for CRF was 47.20 ± 4.34 (ml/kg/min). Results show a very weak relationship between body weight and CRF (r = 0.027). Meanwhile, there was a positive and weak relationship between body height and CRF (r = 0.265). In conclusion, evidence from this study showed no association between anthropometry and cardiorespiratory fitness. However, possibly a good anthropometry characteristic possibly gives the advantage of having good cardiorespiratory fitness. Ideal body weight and height is a potential physiological characteristic in determinants of cardiorespiratory fitness. Anthropometric does have a role as part of holistic monitoring of talented players in future development. Viewing the limitations of this study, further studies involving larger sample size are needed to find actual association with this hypothesis.

Cardiorespiratory fitness assessed with cardiopulmonary exercise testing in patients with juvenile idiopathic arthritis: a systematic review and meta-analysis.

Juvenile idiopathic arthritis (JIA) is the most common type of arthritis in children and adolescents, causing joint damage, chronic pain and disability. Deconditioning is also prevalent in patients with JIA due to both inactivity and the disease progression, resulting in reduced cardiorespiratory fitness (CRF). We aimed to evaluate CRF of patients with JIA compared to healthy controls. This is a systematic review and meta-analysis of studies using cardiopulmonary-exercise-testing (CPET) to examine differences in determinants of CRF between patients with JIA versus healthy controls. The primary outcome was peak oxygen uptake (VO2peak). Literature search involved PubMed, Web of Science and Scopus databases, manual search of article references and grey literature. Quality assessment was undertaken with Newcastle-Ottawa-Scale. From 480 literature records initially retrieved, 8 studies (538 participants) were included in final meta-analysis. VO2peak was significantly lower in patients with JIA compared to controls [weighted-mean-difference, WMD:-5.95 ml/kg/min, 95% CI (-9.26; -2.65)]; Exercise duration as well as VO2peak(%predicted) were found to be significantly impaired in patients with JIA compared to controls [standardized-mean-difference, SMD: -0.67, 95% CI (-1.04; -0.29)] and [WMD: -11.31%, 95% CI (-20.09; -2.53)], respectively, while no significant differences were found in maximum heart rate. VO2peak and other CPET variables were lower in patients with JIA compared to controls, indicating reduced CRF in the former. Overall, exercise programs for patients with JIA should be promoted as part of their treatment to improve physical fitness and reduce muscle atrophy. CRD42022380833.

Diastolic Dysfunction Contributes to Impaired Cardiorespiratory Fitness in Patients with Lung Cancer and Reduced Lung Function Following Chest Radiation.

Cardiorespiratory fitness (CRF) is a robust and independent predictor of cardiovascular health and overall mortality. Patients with lung cancer often have chronic lung disease, contributing to impaired CRF. Radiation to the heart during lung cancer treatment may further reduce CRF. The determinants of CRF in this population are not well understood. We prospectively evaluated 12 patients with lung cancer without known cardiovascular disease with reduced lung function receiving curative intent thoracic radiotherapy to determine whether cardiac diastolic function, as assessed by Doppler echocardiography and N-terminal pro-brain natriuretic peptide (NTproBNP) levels, correlate with CRF measured by peak oxygen consumption (VO2). Doppler-derived measures of diastolic function and serum NTproBNP levels inversely correlated with peak VO2. In a multivariate regression model, NTproBNP was the strongest independent variable associated with peak VO2. These results suggest that diastolic dysfunction further contributes to reduced CRF in patients with lung cancer who have received radiotherapy.

Determinants of cardiorespiratory fitness in very long-term survivors of allogeneic hematopoietic stem cell transplantation: a national cohort study

PurposeSurvivors of allogeneic hematopoietic stem cell transplantation (allo-HSCT) are at risk for cardiopulmonary adverse events. Data on long-term effects on cardiorespiratory fitness are limited. To address the gap in knowledge, we aimed to determine peak oxygen uptake (V̇O2peak) and identify associations between cardiorespiratory fitness and clinical characteristics, self-reported physical activity, cardiac, and pulmonary function.MethodsIn a nationwide, single-center cross-sectional study, 90 survivors [aged median (range) 35 (17–54) years, 56% females] were examined, 17 (6–26) years after allo-HSCT. Myeloablative conditioning comprised busulfan/cyclophosphamide or cyclophosphamide only. Methods included pulmonary function tests, echocardiography, and cardiopulmonary exercise test.ResultsChronic graft-versus-host disease (cGVHD) was found in 31% of the subjects, of whom 40% had bronchiolitis obliterans syndrome (BOS). Seventy-one percent of the survivors did not meet WHO recommendations for physical activity and 42% were overweight. Reduced gas diffusion (DLCO) and systolic ventricular dysfunction (LVEF) were found in 44% and 31%, respectively. For the group, mean (95% CI), V̇O2peak was 36.4 (34.7–38.0) mL/min/kg [89 (85–93)% of predicted]. V̇O2peak was low at 43%. Cardiopulmonary factors and deconditioning were equally common limitations for exercise. In a multiple linear regression model, low V̇O2peak was associated with low DLCO, low LVEF, BOS, overweight, and inactivity.ConclusionHalf of the survivors had reduced cardiorespiratory fitness median 17 years after allo-HSCT. Cardiopulmonary factors and deconditioning were equally common limitations to exercise. We encourage long-term cardiopulmonary monitoring of allo-HSCT survivors and targeted advice on modifiable lifestyle factors.

Determinants of Cardiorespiratory Fitness After Bariatric Surgery: Insights From a Randomised Controlled Trial of a Supervised Training Program

BackgroundSeverely obese patients have decreased cardiorespiratory fitness (CRF) and poor functional capacity. Bariatric surgery–induced weight loss improves CRF, but the determinants of this improvement are not well known. We aimed to assess the determinants of CRF before and after bariatric surgery and the impact of an exercise training program on CRF after bariatric surgery. MethodsFifty-eight severely obese patients (46.1 ± 6.1 kg/m2, 78% women) were randomly assigned to either an exercise group (n = 39) or usual care (n = 19). Exercise training was conducted from the 3rd to the 6th months after surgery. Anthropometric measurements, abdominal and mid-thigh computed tomographic scans, resting echocardiography, and maximal cardiopulmonary exercise testing was performed before bariatric surgery and 3 and 6 months after surgery. ResultsWeight, fat mass, and fat-free mass were reduced significantly at 3 and 6 months, without any additive impact of exercise training in the exercise group. From 3 to 6 months, peak aerobic power (V̇O2peak) increased significantly (P < 0.0001) in both groups but more importantly in the exercise group (exercise group: from 18.6 ± 4.2 to 23.2 ± 5.7 mL/kg/min; control group: from 17.4 ± 2.3 to 19.7 ± 2.4 mL/kg/min; P value, group × time = 0.01). In the exercise group, determinants of absolute V̇O2peak (L/min) were peak exercise ventilation, oxygen pulse, and heart rate reserve (r2 = 0.92; P < 0.0001), whereas determinants of V̇O2peak indexed to body mass (mL/kg/min) were peak exercise ventilation and early-to-late filling velocity ratio (r2 = 0.70; P < 0.0001). ConclusionsA 12-week supervised training program has an additive benefit on cardiorespiratory fitness for patients who undergo bariatric surgery.

Determinants of cardiorespiratory fitness in amateur male cross-country skiers

The aim of the study was to present the performance parameters, their assessment and their predictors in the group of amateur cross-country skiers at the beginning of the preparatory period. For this purpose, incremental exercise tests were carried out on the treadmill. Body composition measurement was performed using impedance analyzer. The main findings of the study were that the most correlated with VO2 relative (max) were percentages of body fat, running speed (maximum) (km/h), running speed (final) (km/h), ventilation (L/min) and physiological cost of running (ml/kg/km). The appointment of the predictors can be an effective tool to assess the efficiency of this group and prepare a proper training plan for them.

Determinants of Cardiorespiratory Fitness in Patients with Heart Failure Across a Wide Range of Ejection Fractions

Impaired cardiorespiratory fitness (CRF) in heart failure (HF) is influenced by a complex array of cardiac and extracardiac factors. The study aimed to identify clinical determinants of CRF measured as peak oxygen consumption (peak VO2) in HF patients, and to determine a peak VO2 prediction model using regression equations. Retrospective analysis of 200 HF patients who completed treadmill cardiopulmonary exercise testing and underwent Doppler echocardiography and/or biomarker analysis on the same day was performed. After univariate linear regression analysis, a multivariate peak VO2 prediction model was developed using significant variables in a stepwise linear regression analysis. In subjects with repeated testing, Pearson's correlation was used to assess correlations between measured and predicted change in peak VO2 (Δpeak VO2) over time. Mean age was 57 years, with 55% being male. Stepwise linear regression was used to generate a weighted model for peak VO2: 30.895 + (-0.112•age[years]) + (0.296•hemoglobin [g/dl]) + (-0.101•E/e'[unit change]) + (-0.202• body mass index [kg/m2]) + (-0.593• N-terminal pro-brain natriuretic peptide [logN pg/ml])) + (-1.349•CRP [log mg/L]). Predicted peak VO2 correlated strongly with measured peak VO2 in HF with reduced ejection fraction and HF with preserved ejection fraction patients (r = +0.63, p<0.001; r = +0.64, p<0.001, respectively). Predicted Δpeak VO2 correlated with measured Δpeak VO2 (r = +0.23, p<0.001). In conclusion, in patients with HF across a wide range of left ventricular ejection fraction, age, systemic inflammation, oxygen carrying capacity, obesity, and elevated filling pressures are the strongest predictors of impaired CRF. The proposed CRF model allows prediction of peak VO2 in HF patients and may be used to estimate peak VO2 changes over time.

Why are some people more fit than others? Correlates and determinants of cardiorespiratory fitness in adults: protocol for a systematic review

BackgroundCardiorespiratory fitness (CRF) is a physical condition that is now well established as a predictor of numerous adverse health outcomes, independent of physical activity levels. In order to be able to improve CRF at the population level and to develop effective interventions and public health programmes, it is important to understand why some people are more fit than others. Therefore, the primary aim of the systematic review described in this protocol is to examine individual and interpersonal factors that are correlated with or determine CRF among adults.MethodsThe review will focus on quantitative studies that investigate any personal and interpersonal correlates and/or determinants of objectively measured CRF among the general, non-symptomatic, non-institutionalized adult population (aged 18–65 years) worldwide. The databases MEDLINE, Embase, and Cochrane Library will be searched to identify all relevant published journal articles, and Google Scholar and Scopus will be searched for grey literature. Studies where CRF is not an outcome variable and experimental studies where participants specifically receive a fitness intervention that increases CRF will be excluded. For each study, data extracted will include, among other variables, study characteristics, methodology for selecting participants into the study as well as the participants’ demographic characteristics, types of correlates and determinants of CRF investigated and their measurement methods, the objective measure of CRF used and its measurement method and validity, and the main reported results on the association between the correlates or determinants and CRF. In addition, observational studies will be assessed for methodological quality and risk of bias using a customized version of the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies by the National Heart, Lung, and Blood Institute. Experimental studies will be assessed using the 27-item Downs and Black “Checklist for Measuring Study Quality”. The final results will be presented as a narrative synthesis of the main findings of all included studies.DiscussionBy consolidating and synthesizing the current research on possible individual and interpersonal correlates and determinants of CRF among adults worldwide, we aim to aid future public health actions, as well as identify gaps in our full understanding of what influences CRF.Systematic review registrationPROSPERO CRD42017055456.

Determinants of Cardiorespiratory Fitness in a Population Sample of Girls and Boys Aged 6 to 8 Years.

There are few studies on determinants of cardiorespiratory fitness (CRF) among girls and boys separately in population samples of children. We therefore investigated the determinants of CRF, assessed by maximal workload per height using allometric scaling, in a population sample of 162 girls and 177 boys aged 6 to 8 years. We used automated bootstrap feature selection and linear regression models. The strongest determinants of CRF among girls were maximal heart rate (HR; standardized regression coefficient [β] = 0.31, P < .001), unsupervised physical activity (β = 0.29, P < .001), lean body mass (β = 0.23, P = .001), and errors in static balance test (β = -0.16, P = .02), accounting altogether for 25.7% of variation in CRF. In boys, unsupervised physical activity (β = 0.24, P < .001), resting HR (β = -0.25, P < .001), hand grip strength (β = 0.21, P = .001), errors in static balance test (β = -0.16, P = .01), organized football (β = 0.16, P = .01), and unsupervised trampoline jumping (β = 0.14, P = .04) were the strongest determinants of CRF, accounting altogether for 29.7% of variation in CRF. These findings suggest that unsupervised physical activity is sufficient in improving CRF in both sexes. Furthermore, larger muscle mass and better balance are associated with higher CRF that has to be taken into account when assessing CRF using maximal cycle ergometer exercise test among children.

Determinants of cardiorespiratory fitness at 3, 6 and 12 months poststroke

Purpose: To better delineate intervention programs, knowledge of the factors that are associated with physical fitness in stroke survivors is crucial. This study aimed to predict cardiorespiratory fitness based on standardized measures along the several dimensions of the International Classification of Functioning, Disability and Health (ICF) model at several time intervals in the first year after stroke. Methods: Forty patients were assessed at 3, 6 and 12 months poststroke. A symptom-limited graded cycle ergometer test was used to assess cardiorespiratory fitness. Outcome variables were VO2 peak and the Oxygen Uptake Efficiency Slope (OUES). Impairments, activity limitations, participation restrictions, personal and environmental factors were assessed to determine predictive factors. Results: Explained variance at 3, 6 and 12 months poststroke was 39%, 55% and 91% for VO2 peak and 55%, 63% and 79% for OUES. A strong association between knee muscle strength and cardiorespiratory fitness was found at each measurement time, explaining up to 72 % of the variance in fitness. At 12 months poststroke, functional mobility, body mass index (BMI) and emotional status also contributed to explain variance. Conclusions: Knee muscle strength was found to be a very strong predictor of cardiorespiratory fitness during the first year after stroke and functional mobility became important at 12 months poststroke.Implications for RehabilitationKnee muscle strength was found to be a very strong predictor of cardiorespiratory fitness during the first year after stroke and functional mobility became important at 12 months post-stroke.Cardiorespiratory endurance training should be implemented with strength-developing exercises of both lower limbs, with emphasis on the weaker paretic side.

Determinants of cardiorespiratory fitness in patients with chronic obstructive pulmonary disease, focusing on activities parallel to daily living.

The purpose of this study was to examine whether activities parallel to daily living (APDL) constitute a determinant index of cardiorespiratory fitness in patients with chronic obstructive pulmonary disease (COPD). Four functional physical fitness parameters were investigated in 38 male patients (mean age 69.8 +/- 6.7 years) with moderate to severe COPD. The parameters measured were muscular strength (grip strength), muscular endurance strength (arm curl, keeping a half-squat position) and regulation (walking around two cones). In addition, cardiorespiratory fitness was measured using a 6-min walking distance test (6MWD) and peak oxygen uptake (VO(2peak)) was measured during bicycle ergometer testing. Maximal inspiratory pressure (MIP) and maximal expiratory pressure were measured so as to quantify respiratory muscle strength. There were significant correlations (P < 0.05) between the VO(2peak), muscular endurance, pulmonary function and respiratory muscle strength. There were also significant correlations of VO(2peak) to muscular endurance, muscular strength, muscular endurance strength and regulation. In stepwise multiple regression analysis, per cent predicted forced expiratory volume in 1 s and MIP appeared to be significant determinants of VO(2peak), showing a total variance of 56% (P < 0.05). For the 6MWD, the significant determinants were forced vital capacity, MIP and performance in the half-squat test, showing a variance of 59% (P < 0.05). The results suggest that cardiorespiratory fitness is strongly affected by MIP, pulmonary function and muscular endurance strength, as APDL depend on lower-limb use.

Determinants of VO2 peak in Children from Taiwan

This study sought to examine factors that could influence the accuracy of estimating school children's VO2peak using cardiorespiratory (CR) fitness field test measurements. We randomly recruited 38 male subjects, aged 11‐12 years, from a district elementary school male population (n = 165) for the study. To test the reliability of the CR fitness field test items, all 165 male students underwent the following measurements on two different days: 1) 800‐m run‐walk test (RWT); 2) 3‐min bench step test (BST); 3) heart rate (resting, peak exercise and recovery); 4) blood pressure (SBP/DBP); 5) skinfold thickness (SF); and 6) height, weight and body mass index. Test‐retest reliability of the field test measurements ranged from 0.42 to 0.86 (p < 0.05) which is considered moderate to high. The measurements obtained from the 38 students were used as independent variables for developing a regression equation. VO2peak was used as the dependent variable. Stepwise multiple regression analysis revealed that RWT score, subscapular SF (SFsub) and SBP are strong predictors of VO2peak. The total variance explained by these independent variables of the prediction equation was 69%. The equation: VO2peak (ml kg‐1min‐1) = 96.806 ‐ 0.0779 (800‐m RWT, sec) ‐ 0.2078 (SBP, mmHg) ‐ 0.5816 (SFsub, mm), had a total error of 4.47 ml kg‐1 min‐1 and coefficient of variation (CV) of 8.5%. In this study, the 800‐m RWT had a higher correlation coefficient with VO2peak than the 3‐min BST. We concluded that the 800‐m RWT, SFsub and SBP are significant determinants of CR fitness for Chinese boys aged 11‐12 years. Descriptors: Blood pressure, cardiorespiratory endurance, fitness test, VO2peak.

Longitudinal variations in maximal oxygen intake with age and activity.

Longitudinal variations in maximal oxygen intake with age and activity.