Low Cardiorespiratory Fitness Research Articles

The joint profiles of cardiorespiratory fitness and muscle strength on daily physical activity levels in patients with symptomatic peripheral artery disease: A cross-sectional study.

In peripheral artery disease (PAD) patients, the joint profile of low strength and cardiorespiratory fitness on movement behaviors, specifically physical activity levels and sedentary time, remains unclear. To investigate the joint profiles between cardiorespiratory and neuromuscular fitness and daily physical activity among PAD patients. Cross-sectional study in a sample of 155 PAD patients. We measured their physical activity level per week using accelerometers, assessed their muscle strength through a sit-to-stand test and cardiorespiratory fitness through a six-minute walk test. Patients were categorized into three groups: those with high strength and cardiorespiratory fitness (NC, n = 28), those with at least one component classified as low (1C, n = 88), and those with both components classified as low fitness (2C, n = 39). The patients in the 1C and 2C groups spent less time engaged in low-light and moderate activities compared to the NC group (low-light: NC: 2291 ± 680 minutes/week vs. 1C: 1826 ± 649 minutes/week vs. 2C: 1885 ± 651 minutes/week, p = .005; moderate: NC: 2617 ± 796 minutes/week vs. 1C: 2071 ± 767 minutes/week vs. 2C: 2092 ± 776 minutes/week, p = .005) and the patients in the 2C group spent less time engaged in vigorous activities compared to the NC and 1C groups (NC: 155 ± 148 minutes/week vs. 1C: 110 ± 110 minutes/week vs. 2C: 64 ± 70 minutes/week, p = .003). PAD patients with low strength and/or cardiorespiratory fitness are more likely to spend less time engaging in low-light and moderate physical activities and patients with low fitness in both components are more likely to spend less time engaging in vigorous physical activity.

Adolescent Cardiorespiratory Fitness and Future Work Ability

Although research indicates that low fitness in youth is associated with a higher risk of chronic disability in men, the association of fitness in adolescence with work ability in working men and women remains unknown. To examine the associations of adolescent health-related physical fitness with future work ability. This 45-year observational cohort study, conducted in Finland, examined the direct and indirect longitudinal associations of objectively measured health-related fitness in adolescence (in 1976) with self-reported work ability and sickness absence in early middle age (in 2001) and the Work Ability Index in late middle age (in 2021). A countrywide stratified random baseline sample included fitness measurements for cardiorespiratory fitness (CRF) (running 1.5 km for girls and 2 km for boys), musculoskeletal fitness (MF; standing broad jump and sit-ups for both sexes, pull-ups for boys, and flexed-arm hang for girls), and height and weight, from which body mass index (BMI) was calculated. Structural equation modeling-based path analysis, adjusted for age and sex at baseline and for educational level, work-related physical strain, and leisure-time physical activity in late middle age, was conducted. Data analysis was performed from January to July 2023. Self-reported work ability was measured with structured questions in early middle age and with the validated Work Ability Index in late middle age. The final sample from longitudinal analyses (1207 individuals; 579 [48%] male individuals) consisted of participants with fitness measurement from age 12 to 19 years, and work ability assessment from age 37 to 44 years and/or age 57 to 64 years. Higher adolescent CRF was associated with higher work ability (839 participants; β = 0.12; 95% CI, 0.01 to 0.22; P = .03) and lower sickness absence (834 participants; β = -0.07; 95% CI, -0.12 to -0.02; P = .004) in early middle age and, indirectly, mediated by work ability in early middle age, with a higher work ability at the end of working age (603 participants; β = 0.04; 95% CI, 0.001 to 0.08; P = .04). The results remained consistent in both sexes and after adjustment for the confounders. Neither MF nor BMI was associated with work ability (MF, 1192 participants; β = -0.07; 95% CI, -0.17 to 0.03; BMI, 1207 participants, β = 0.09; 95% CI, -0.004 to 0.19) or sickness absence (MF, 1185 participants, β = 0.02; 95% CI, -0.03 to 0.06; BMI, 1202 participants, β = -0.03; 95% CI, -0.09 to 0.03) in early middle age or with late middle age work ability, mediated by work ability in early middle age (MF, 603 participants, β = -0.02; 95% CI, -0.06 to 0.01; BMI, 603 participants, β = 0.03; 95% CI, -0.004 to 0.07). These findings suggest that low CRF in youth is associated with poor work ability at the middle and end of working life, which highlights the informative and prognostic value of CRF assessment early in youth. Enhancing CRF in the first decades of life might contribute to better work capacity and productivity in the labor force, which would have implications for health, quality of life, society, and the economy.

Abstract P345: Is a Fixed Value of the Rate of Gas Exchange Appropriate to Indicate the Maximum Effort of Obese and Nonobese Adults Undergoing a Treadmill Cardiopulmonary Exercise Test?

Introduction: Obese individuals present a higher O2 uptake/workload during a treadmill cardiopulmonary exercise test (CPET) in addition to chronotropic and biomechanical impairment, which preclude them, many times, from reaching a maximal rate of gas exchange (Rmax) > 1.0. Therefore, it is necessary to develop reference values for Rmax for a treadmill CPET according to age, sex, and a wide range of body mass index (BMI). Objectives: To establish reference values for Rmax for a treadmill CPET according to age, sex, and BMI. Methods: We re-examined 1,612 treadmill ramp CPETs of adults (893 women), of which 772 were obese (BMI ≥ 30 kg/m 2 ). We excluded tests of nonobese participants with HRmax < 85% of predicted, of any participant with a rate of perceived exertion in the BORG scale < 4 (intense), and of those that we had operational problems during the test. We produced a Rmax percentile table according to sex, age (< 33, 34 to 46, and > 46 years), and BMI (< 30 and ≥ 30 kg/m 2 ). We fit stepwise multiple regressions to investigate the influence of age, sex, BMI, and cardiovascular risk on Rmax. We also presented an obesity-specific equation to estimate maximum heart rate (HRmax). Results: We evaluated 442 eutrophic participants (BMI < 25 kg/m 2 ), 398 were overweighted (BMI = 25 - 29.99 kg/m 2 ), 295 had class 1 obesity (BMI = 30 - 34.99 kg/m 2 ), 247 had class 2 obesity (BMI = 35 - 39.99 kg/m 2 ) and 230 had class 3 obesity (BMI ≥ 40 kg/m 2 ). Age, sex, and BMI were the main determinants of Rmax (R 2 = 0.195). The table with percentiles confirmed that the lower limits of Rmax did not reach 1.0, especially in older, obese, and female participants (Table 1). In the obese participants, we could predict HRmax as 195.2 - (0.796 x age). Conclusions: The Rmax values in a treadmill CPET should be chosen considering attributes such as age, sex, and BMI. Our results suggest that fixed values of Rmax are not appropriate to indicate maximum effort, especially in people with low cardiorespiratory fitness.

Abstract P285: Relationship Between Body Mass Index, Waist Measurement, Six-Minute Walk Performance and Whole-Body Strength in Adults With Cardiovascular Disease: Findings From the Lifestyle Heart Health Study

Introduction: Cardiovascular disease (CVD) is the leading cause of death, killing 17.9 million people annually worldwide. Key risk factors include physical inactivity, overweight/obesity, high blood pressure, high cholesterol which worsen with age, and smoking and excessive alcohol intake. Six-minute walk (6MW) performance and whole-body muscle strength are both related to cardiovascular mortality and also worsen with age, particularly in the absence of physical activity. The aims of this study were to understand levels of cardiovascular risk and compliance to usual medical treatment (medication, lifestyle modifications) in a high socioeconomic Australian population, and to identify relationships between key risk factors, 6MW and muscle strength. A secondary aim was to help inform development of the Lifestyle Heart Health Education Program. Methods: This was a cross-sectional study of 473 people with CVD in Sydney. Class was classified based on the Australian socioeconomic index for areas. Conditions were defined according to Australian national guidelines. Medical history, body mass index (BMI), waist measurement, whole-body muscle strength and 6MW measurements were assessed. Simple linear and stepwise regressions were used to assess potential relationships. Results: Mean age of the cohort was 66.8±11.6; range 21-94 yrs; 68.5% female; socioeconomic index was deemed high. All participants had CVD, of which 25% were on aspirin. Hypertension was prevalent in 65% (38% on anti-hypertensives); 65% had dyslipidaemia (40% on a statin); 91% had a BMI over 26.0; and 85% of males and 80% of females had a waist measurement over gender-specific heart health recommendations. Less than 3% of the cohort smoked, and less than 10% consumed alcohol at a level deemed high-risk. Almost 20% of the cohort were at risk of CV mortality according to 6MW performance with scores less than 350 metres. Waist measurement, BMI, and blood pressure were the greatest risk factors across the cohort. Muscle strength (r=-0.34; r 2 =0.17; p<0.001) and 6MW performance (r=-0.37; r 2 =0.17; p<0.001) both decreased with age. BMI and age were the most significant predictors of 6MW (r=-0.45; r 2 =0.20; p=0.004) and whole-body strength (r=0.49; r 2 =0.24; p<0.001) in females; waist and age were the most significant predictors of 6MW (r=-0.38; r 2 =0.14; p=0.11) and whole-body strength (r=0.41; r 2 =0.17; p=0.04) in males. Conclusion: Whilst alcohol and smoking campaigns are working to reduce consumption of these harmful substances, low cardiorespiratory and muscular fitness and overweight/obesity remain highly prevalent. Population-level interventions such as the Lifestyle Heart Health Program that aim to reduce weight and waist and improve physical activity, walking ability and muscle strength are urgently needed to reduce cardiovascular risk and mortality.

Cardiorespiratory and Muscular Fitness in Children and Adolescents with Obesity.

Examine the current state of literature related to the impact of obesity in children and adolescents on health-related physical fitness and the resultant cardiometabolic disease risk. Cardiorespiratory fitness of children and adolescents has declined over the past few decades which corresponds with an increase in obesity rates. Children with obesity are more likely to have low cardiorespiratory fitness which is associated with higher cardiometabolic disease risk and poorer mental health. The impact of obesity on muscular fitness in children and adolescents is more difficult to ascertain, but in general measures of physical function are lower in children with obesity which has also been associated with higher cardiometabolic disease risk. Components of health-related physical fitness are trending negatively in children and adolescents and appear to be related to the increase in prevalence of obesity. The resultant cardiometabolic disease risk has also risen which suggests a greater disease burden in the future. These disparaging findings highlight the need for aggressive interventions to improve physical fitness in children and adolescents.

Cardiorespiratory fitness and muscular fitness correlates in youth: A hierarchy of behavioral, contextual, and health-related outcomes

ObjectivesDespite the health importance of identifying correlates of physical fitness in youth, no investigation to date has explored the influence of behavioral, health-related, and contextual correlates simultaneously. We investigated the hierarchical relationship of multiple modifiable correlates favoring or diminishing cardiorespiratory and muscular fitness in youth. DesignCross-sectional investigation. MethodsIn a sample of 5174 children and adolescents, 31 correlates were hierarchized according to their impact on cardiorespiratory and muscular fitness assessed using the FITESCOLA® fitness battery. A Chi-squared Automatic Interaction Detection approach was employed and measures of correlation and association were used to investigate the relationship between physical fitness and correlates. ResultsIn children, body mass index was the most relevant factor to discriminate between high and low cardiorespiratory and muscular fitness of the upper, middle, and lower body. While body mass index was more important than any other correlate to differentiate levels of upper and lower body muscular fitness during adolescence, specific characteristics of sports participation emerged as key factors to discriminate between high and low cardiorespiratory fitness and middle body muscular fitness. Other correlates, including the self-report of active recess time, active commuting to school, favorable neighborhood conditions, and limited time on screens and cellphones, were demonstrative of favorable physical fitness levels. ConclusionsBoth body composition and sports-related characteristics emerged as the two most relevant factors of physical fitness in youth. Additional health benefits may be obtained from building supportive environments for sports and healthy exercise habits within the household and at different school education levels.

Reference values for the 6-min walking test in children and adolescents living in a moderate altitude region of Peru

BackgroundThe assessment of cardiorespiratory fitness is important because it allows the identification of subgroups with poor health status and the targeting of effective intervention strategies to improve health.ObjectiveTo compare the cardiorespiratory capacity of children and adolescents living in a moderate altitude region of Peru with international studies and to develop reference values for the 6-min walk test (6MWT) according to age and sex.MethodologyA descriptive cross-sectional study of schoolchildren from a region of moderate altitude in Peru was carried out. A total of 704 schoolchildren (400 males and 304 females) with an age range of 6 to 17 years were studied. Weight, standing height, waist circumference (WC), body mass index (BMI) and tri-ponderal mass index (TMI) were evaluated. The 6MWT was assessed in a straight line over a distance of 30 m. Percentiles were created through the LMS method [L (skewness: lambda), M (median: mu) and S (coefficient of variation: Mu)].ResultsThere were discrepancies in cardiorespiratory fitness performance with international studies by age and sex. The schoolchildren in the study reached stability and the highest number of meters in the last two age ranges (14 to 15 years: 698.1 m and 16 to 17 years 686.3 m in males). While females (14 to 15 years: 698.1 m and 16 to 17 years: 686.3 m). The proposed percentile values show ascending values as age advances. The cut-off points adopted are: low cardiorespiratory fitness < p25, moderate p25 to p75 and high cardiorespiratory fitness p > 75.ConclusionWe verified that the cardiorespiratory fitness evaluated by means of the 6MWT is ascending with the course of age. Even the performance with other countries is heterogeneous at early and middle ages, stabilizing during adolescence. The proposed reference values can be used to evaluate and monitor cardiorespiratory fitness during physical education classes.

Anxiety Predicts Worse Cardiorespiratory Fitness Outcomes in Cardiac Rehabilitation for Lower Socioeconomic Status Patients.

The purpose of this study was to show that patients in cardiac rehabilitation (CR) with lower socioeconomic status (SES) have worse clinical profiles and higher rates of psychiatric difficulties and they have lower cardiorespiratory fitness (CRF) improvements from CR than their counterparts with higher SES. Improvement in CRF during CR predicts better long-term health outcomes. Research suggests that higher anxiety impairs CRF in structured exercise regimes and is overrepresented among patients with lower SES. However, no study has determined whether this relationship holds true in CR. This study is a secondary analysis of a randomized controlled trial to improve CR attendance among patients with lower SES. Anxiety (ASEBA ASR; Achenbach System of Empirically Based Assessment, Adult Self Report) and CRF measures (metabolic equivalent tasks [METs peak ]) were collected prior to CR enrollment and 4 mo later. Regression was used to examine the association of anxiety with CRF at 4 mo while controlling for other demographic and clinical characteristics. Eight-eight participants were included in the analyses, 31% of whom had clinically significant levels of anxiety ( T ≥ 63). Higher anxiety significantly predicted lower exit CRF when controlling for baseline CRF, age, sex, qualifying diagnosis, and number of CR sessions attended ( β =-.05, P = .04). Patients with clinically significant levels of anxiety could be expected to lose >0.65 METs peak in improvement. The results from this study suggest that anxiety, which is overrepresented in populations with lower SES, is associated with less CRF improvement across the duration of CR. The effect size was clinically meaningful and calls for future research on addressing psychological factor in CR.

Sex Differences in Depressive Symptoms in 1308 Patients Post-Stroke at Entry to Cardiac Rehabilitation.

The objective of this study was to determine whether a sex difference exists in the prevalence of post-stroke depressive symptoms (PSDS) at entry to cardiac rehabilitation (CR) and to determine the correlates of PSDS in all patients, and in women and men separately. People post-stroke at entry to CR from database records (2006-2017) were included. Bivariate analyses identified PSDS correlates (≥16 on the Center for Epidemiologic Studies Depression Scale) in all patients and women and men separately. Patients (n = 1308, 28.9% women), mean age of 63.9 ± 12.9 yr, were 24.2 ± 9.9 mo post-stroke at CR entry. Among all patients, 30.0% had PSDS. A greater proportion of women than men had PSDS (38.6 vs 26.6%; P < .001). Correlates of PSDS in all patients were sex (women) (OR = 1.6: 95% CI, 1.14-2.12), being unemployed, ≤60 yr old, prescribed antidepressant medication, having lower cardiorespiratory fitness (peak oxygen uptake [V̇ o2peak ]), chronic obstructive pulmonary disease (COPD), higher body mass index (BMI), no transient ischemic attack, and longer time from stroke to CR entry (>12 mo). Correlates in women were being obese (BMI ≥ 30), 51-70 yr old, prescribed antidepressant medication, and not married. Correlates in men were being ≤60 yr old, unemployed, prescribed antidepressant medication, having lower V̇ o2peak , sleep apnea, COPD, and no hypertension. Women were disproportionately affected by PSDS at entry to CR in bivariate and multivariable analyses. Women and men had mostly unique correlates of PSDS, indicating tailored strategies to address PSDS are required. PSDS disproportionately affected patients with longer delay to CR entry, suggesting efforts should target timely referral to facilitate earlier and repeated assessments and management.

Exploring the role of sex in the association of late chronotype on cardiorespiratory fitness.

Circadian rhythms differ between young adult males and females. For example, males tend to be later chronotypes, preferring later timing of sleep and activity, than females. Likewise, there are sex differences in body composition and cardiorespiratory fitness. Few studies have investigated the association between circadian rhythms, cardiorespiratory fitness, and body composition. We sought to determine whether chronotype and circadian phase were associated with cardiorespiratory fitness, body composition, and anthropometric measures in sedentary males and females. Fifty-nine adults participated in the study. Circadian phase and chronotype were measured using dim light melatonin onset (DLMO) and the Morningness-Eveningness Questionnaire (MEQ) score. We used peak oxygen uptake (VO2peak ) results from a maximal graded exercise test to assess cardiorespiratory fitness. Body composition, BMI, and circumferences were collected as markers of adiposity. We observed a sex difference in the association between DLMO and VO2peak . For males, a later DLMO was associated with a lower VO2peak . VO2peak did not vary based on DLMO in females. Later circadian phase was also associated with increased body fat percentage, fat mass index, and abdominal circumference in males, but not females. Collectively, these results suggest that males who are later chronotypes may be at risk of obesity and low cardiorespiratory fitness.

Comparing cardiorespiratory fitness and physical activity levels between third- and fifth-year medical students in a South African university.

Cardiovascular disease (CVD) risk factors such as sedentary behaviour, decreased physical activity (PA), and low cardiorespiratory fitness lead to an increased and accelerated risk of cardiovascular disease and mortality. Medical students tend to adopt sedentary lifestyles due to a demanding curriculum. This may have a negative effect on CVD risk factors and cardiorespiratory fitness levels of medical students. To compare physical activity and cardiorespiratory fitness levels in a cohort of third- and fifth-year undergraduate medical students in a South African university. Data from 123 third-year and 139 fifth-year medical students in the Graduate Entry Medical Programme (GEMP) at the Faculty of Health Sciences, University of the Witwatersrand, were collected. Measurements included CVD risk factors, height, weight, blood pressure, waist circumference, cardiorespiratory fitness, physical activity vital signs and pre-participation health screening questionnaires. Descriptive statistics were presented as mean ± standard deviation or median [interquartile range] depending whether the data were normally distributed or not. Both groups had low cardiorespiratory fitness when compared to norm values (GEMPI VO2 peak was 29.1 ± 5.9 ml.kg-1.min-1 and GEMPIII VO2 peak was 30.0[11.0] ml.kg-1.min-1). Most participants did not meet WHO physical activity requirements (GEMP I: 72%; GEMP III: 78%). There were significant differences in BMI (p=0.046), diastolic blood pressure (p=0.034) and VO2 peak (p=0.00001) between students meeting and not meeting WHO physical activity requirements (p<0.05). Third- and fifth-year medical students at a South African university fail to meet recommended WHO physical activity levels and are below cardiorespiratory fitness norms. Therefore, medical institutions should promote and implement targeted physical activity interventions to reduce the prevalence of low fitness levels and the associated health hazards among their students.

Sex modulates the diet-induced changes to the plasma lipidome in a rat model of cardiorespiratory fitness

ObjectiveIndividuals with higher intrinsic cardiorespiratory fitness (CRF) experience decreased rates of cardiometabolic disease and mortality, and high CRF is associated with increased utilization of fatty acids (FAs) for energy. Studies suggest a complex relationship between CRF, diet, and sex with health outcomes, but this interaction is understudied. We hypothesized that FA utilization differences by fitness and sex could be detected in the plasma metabolome when rats or humans were fed a high carbohydrate (HC) or high fat (HF) diet. MethodsMale and female rats selectively bred for low (LCR) and high (HCR) CRF were fed a chow diet or a sucrose-free HF (45 % fat) or HC (10 % fat) diet. Plasma samples were collected at days 0, 3, and 14. Human plasma data was collected from male and female participants who were randomized into a HC or HF diet for 21 days. Samples were analyzed using liquid chromatography-mass spectrometry and regression statistics were used to quantify the effect of diet, CRF, and sex on the lipidome. ResultsIn rats, the baseline lipidome is more significantly influenced by sex than by CRF, especially as elevated diglycerides, triglycerides, phosphatidylcholines, and lysophosphatidylcholines in males. A dynamic response to diet was observed 3 days after diet, but after 14 days of either diet, the lipidome was modulated by sex with a larger effect size than by diet. Data from the human study also suggests a sex-dependent response to diet with opposite directionality of affect compared to rats, highlighting species-dependent responses to dietary intervention.

The association between the dietary inflammatory index and cardiorespiratory fitness in United States young adults: a cross-sectional study from the National Health and Nutrition Examination Study, 1999-2004.

Cardiorespiratory fitness (CRF) is a vital indicator of overall health and cardiovascular efficiency. Systemic inflammation significantly impacts CRF, and reducing systemic inflammation may serve as an effective strategy to improve CRF. Diet plays a crucial role in systemic inflammation, but daily dietary intake typically involves multiple elements rather than a single nutrient. The Dietary Inflammatory Index (DII) provides an overall assessment of dietary inflammation on the basis of the anti-inflammatory and pro-inflammatory effects of the nutrients consumed. However, the relationship between DII and CRF is not yet well understood. To examine the association between the DII and CRF. This study analyzed 3,087 participants from the National Health and Nutrition Examination Survey (NHANES) between 1999 and 2002. The study subjects were divided into three distinct groups by DII tertile: T1 (n = 1,027), T2 (n = 1,029), and T3 (n = 1,031). The associations between DII levels and CRF were examined via logistic regression analysis and restricted cubic splines (RCSs). Elevated DII scores were significantly linked to low CRF levels. Compared with those in the lowest tertile, participants in the highest DII tertile exhibited a greater prevalence of low CRF (T1: 10.85%, T2: 16.32%, T3: 19.31%). In the model with full adjustments, elevated scores on the DII were consistently linked with a heightened likelihood of low CRF (OR: 1.17, 95% CI: 1.07-1.28; P < 0.001). Compared with those in the T1 group, participants with higher DIIs had an increased risk of lower CRF (T2: OR: 1.42, 95% CI: 1.01-2.01, P = 0.046; T3: OR: 1.71, 95% CI: 1.22-2.40, P = 0.003). Additionally, a significant interaction (P = 0.045) between sex and the DII for low CRF was observed within the population. A higher DII score is linked to an elevated risk of low CRF. Moreover, sex can impact CRF, with women being more prone to low CRF.

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

BackgroundThe 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. MethodsWe 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. ResultsIn 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. ConclusionImplementing 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.

DECONSTRUCTING MULTIMORBIDITY AND MUSCLE MITOCHONDRIAL RESPIRATION AND ENERGETICS IN OLDER ADULTS

Abstract Lower cardiorespiratory fitness among older adults is associated with greater multimorbidity burden, including cardiovascular disease, cancer, and dementia. Those with poorer muscle mitochondrial energetics also have lower cardiorespiratory fitness. We have previously shown lower mitochondrial respiration and energetics (OXPHOS and ATPmax) have higher morbidity burden using a summary measure, but the associations among specific conditions have not been examined. We leverage data from the SOMMA cohort (N=856, 76.4yrs, 59% women, 85.5% white); participants self-reported physician diagnosis of 11 age-related conditions (i.e., cancer, cardiac arrhythmia, chronic kidney disease (CKD), chronic obstructive pulmonary disease, coronary heart disease (CHD), depression, diabetes). Mitochondrial respiration was assessed by high-resolution respirometry of vastus lateralis using permeabilized fiber bundles. 31P magnetic resonance spectroscopy of the quadriceps measured ATPmax. In adjusted logistic models with beta-coefficients reported per SD decrement in each mitochondrial measure, fatty-acid-supported Leak respiration was associated with CKD (OR: 2.3(95%CI=1.2,4.3)), fatty acid and complex I&amp;II supported oxidative phosphorylation (OXPHOS) with depression (OR: 1.8(95%CI=1.1,2.7)). Many respirometry measures and ATPmax associated with diabetes, with maximal electron transport system (ETS) capacity having the highest odds (OR: 1.5(95%CI=1.1,2.0)). No other associations were statistically significant for conditions listed above. These results indicate that mitochondrial respiration and energetics are more impaired in depression, kidney disease, and diabetes. This raises new questions about the role of mitochondrial respiration and energetics as cause or consequences of these conditions. Overall, our analyses suggest compromised mitochondrial function may have implications for specific aging-related conditions, and global measures of morbidity burden may not reflect these distinctions.

Low Response to Aerobic Training in Metabolic Disease: Role of Skeletal Muscle.

Aerobic exercise is established to increase cardiorespiratory fitness (CRF), which is linked to reduced morbidity and mortality. However, people with metabolic diseases such as type 1 and type 2 diabetes may be more likely to display blunted improvements in CRF with training. Here, we present evidence supporting the hypothesis that altered skeletal muscle signaling and remodeling may contribute to low CRF with metabolic disease.

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.

Cardiorespiratory fitness and morbidity and mortality in patients with non-small cell lung cancer: a prospective study with propensity score weighting

Introduction This study aimed to investigate the association between cardiorespiratory fitness (CRF) and perioperative morbidity and long-term mortality in operable patients with early-stage non-small cell lung cancer (NSCLC). Patients and Methods This prospective study included consecutive patients with early-stage NSCLC who underwent presurgical cardiopulmonary exercise testing between November 2014 and December 2019 (registration number: ChiCTR2100048120). Logistic and Cox proportional hazards regression were applied to evaluate the correlation between CRF and perioperative complications and long-term mortality, respectively. Propensity score overlap weighting was used to adjust for the covariates. We performed sensitivity analyses to determine the stability of our results. Results A total of 895 patients were followed for a median of 40 months [interquartile range 25]. The median age of the patients was 59 years [range 26–83], and 62.5% were male. During the study period, 156 perioperative complications and 146 deaths were observed. Low CRF was associated with a higher risk of death (62.9 versus 33.6 per 1000 person-years; weighted incidence rate difference, 29.34 [95% CI, 0.32 to 58.36] per 1000 person-years) and perioperative morbidity (241.6 versus 141.9 per 1000 surgeries; weighted incidence rate difference, 99.72 [95% CI, 34.75 to 164.70] per 1000 surgeries). A CRF of ≤ 20 ml/kg/min was significantly associated with a high risk of long-term mortality (weighted hazard ratio, 1.98 [95% CI, 1.31 to 2.98], p < 0.001) and perioperative morbidity (weighted odds ratio, 1.93 [1.28 to 2.90], p = 0.002) compared to higher CRF. Conclusion The study found that low CRF is significantly associated with increased perioperative morbidity and long-term mortality in operable patients with early-stage NSCLC.

Children with cancer and their cardiorespiratory fitness and physical function-the long-term effects of a physical activity program during treatment: a multicenter non-randomized controlled trial.

We aimed to determine the effects of a classmate-supported, supervised, in-hospital physical activity program during treatment primarily on cardiorespiratory fitness and secondarily on physical function. A multicenter non-randomized controlled intervention study including children diagnosed with cancer, 6-18 years at diagnosis treated with chemo-/radiotherapy. The intervention comprised (i) an educational session on cancer in the child's school class; (ii) selection of two "ambassadors"-classmates who were co-admitted, supporting the child's everyday hospital life; and (iii) supervised in-hospital physical activity from diagnosis and throughout intensive treatment. One-year post-treatment, physical testing included cardiorespiratory fitness (primary outcome), Sit-to-Stand test, Timed-Up-and-Go, and Handgrip Strength. The intervention group included 75 of 120 children (61% boys, 13.4 ± 3.1 years); the control groups included 33 of 58 children with cancer (58% boys, 13.5 ± 2.5 years), and 94 age- and sex-matched children without a cancer history. One-year post-treatment, cardiorespiratory fitness tended to be higher in the intervention group (37.0 ± 6.0 mL/kg/min) than in the patient control group with cancer (32.3 ± 9.7 mL/kg/min) (mean difference 4.7 [0.4 to 9.1], p = 0.034). The intervention group performed better in the secondary outcomes. Compared with community controls, bothpatient groups had lower cardiorespiratory fitness. The patient control group had lower Sit-to-Stand, Timed Up and Go, and Handgrip Strength, while the intervention group had strength comparable to that of the community controls. Peer-supported, supervised, in-hospital physical activity during treatment may improve cardiorespiratory fitness and muscle strength 1-year post-treatment in children with cancer; however, survivors continue to have lower cardiorespiratory fitness than community controls. Children with cancer may benefit from in-hospital physical activity in improving long-term cardiorespiratory fitness and muscle strength.

Sedentarism in Recreational Marathon Runners.

Although it has been previously observed that sedentary behavior (SB) was not related to training duration in marathon runners, little information existed about the relationship of SB with training, anthropometric and physiological characteristics in this population. This study aimed to investigate the prevalence of SB and its correlation with performance parameters (such as body fat percentage, maximal oxygen uptake and weekly training volume) as well as its variation by sex and day (ie, weekdays versus weekend) in recreational marathon runners. A total of 151 finishers (women, n = 29; men, n = 122; age 43.1 (8.7) years, mean (standard deviation)) in the Athens marathon 2017 performed a series of anthropometric and physiological tests, and completed the Multi-context sitting time questionnaire. SB did not correlate with anthropometric and physiological characteristics and no difference in these characteristics was shown between low and high sedentary participants (p > 0.05). SB did not differ between women and men (p > 0.05), but differed between working and non-working days (p < 0.05). In contrast to previous findings on the general population indicating an association of a high SB with a low cardiorespiratory and muscular fitness, our finding of no correlation between SB and physical fitness in marathon runners suggested that endurance exercise might offset the negative effects of SB.