Low Cardiorespiratory Fitness Research Articles

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.

Associations that Cardiorespiratory Fitness and Body Mass Index Loss Have with Deficit Accumulation Frailty.

Lower cardiorespiratory fitness and obesity may accelerate aging processes. The degree to which changes in fitness and body mass index (BMI) may alter the rate of aging may be important for planning treatment. We assessed cross-sectional and longitudinal associations that cardiorespiratory fitness and BMI had with a deficit accumulation frailty index (FI). Fitness, based on standardized graded exercise tests, and weight to calculate BMI at baseline and year 4 were collected from 3944 participants aged 45-76 yr in the Action for Health in Diabetes (Look AHEAD) randomized controlled clinical trial. A validated 38-item deficit accumulation FI was used as a marker of aging. Associations between baseline and changes in fitness and BMI with changes in FI were assessed using linear models. Both baseline and 4-yr changes in fitness and BMI were independently associated with 4-yr changes in frailty (all P < 0.001). Mean (95% confidence interval) changes in FI ranged from -0.019 (-0.024, -0.013) for participants in the group with the greatest fitness increase and BMI loss to 0.029 (0.024, 0.034) for participants in the group with the greatest fitness loss and BMI gain. Associations of 4-yr changes in fitness and BMI with FI changes were similar across subgroups based on age, sex, baseline BMI, diabetes duration, and cardiovascular disease history. Increased fitness across 4 yr was associated with less FI accumulation independent of baseline fitness. Adults with type 2 diabetes and overweight or obesity may slow aging processes captured by an FI by increasing their cardiorespiratory fitness and losing weight.

Influence of cardiorespiratory fitness and body composition on resting and post-exercise indices of vascular health in young adults

Poor cardiorespiratory fitness may mediate vascular impairments at rest and following an acute bout of exercise in young healthy individuals. This study aimed to compare flow mediated dilation (FMD) and vascular augmentation index (AIx75) between young adults with low, moderate, and high levels of cardiorespiratory fitness before and after an acute bout of aerobic exercise. Forty-three participants (22 men; 21 women) between 18 and 29 years of age completed the study. Participants were classified into low, moderate, and high health-related cardiorespiratory fitness groups according to age- and sex-based relative maximal oxygen consumption (V˙O2 max) percentile rankings. FMD was performed using Doppler ultrasound and AIx75 was performed using pulse wave analysis at baseline and 60-min after a 30-min bout of treadmill running at 70% V˙O2 max. A significant interaction (p ​= ​0.047; ηp2 ​= ​0.142) was observed, with the moderate fitness group exhibiting a higher FMD post-exercise compared with baseline ([6.7% ​± ​3.1%] vs. [8.5% ​± ​2.8%], p ​= ​0.028; d ​= ​0.598). We found a significant main effect of group for AIx75 (p ​= ​0.023; ηp2 ​= ​0.168), with the high fitness group exhibiting lower AIx75 compared to low fitness group ([−10% ​± ​10%] vs. [2% ​± ​10%], respectively, p ​= ​0.019; g ​= ​1.07). This was eliminated after covarying for body fat percentage (p ​= ​0.489). Our findings suggest that resting FMD and AIx75 responses are not significantly influenced by cardiorespiratory fitness, but FMD recovery responses to exercise may be enhanced in individuals with moderate cardiorespiratory fitness levels.

Exercise for chronic kidney disease: effects on vascular and cardiopulmonary function.

Patients with chronic kidney disease (CKD) have an exacerbated prevalence of cardiovascular disease (CVD). Vascular dysfunction, characterized by impaired endothelial function and arterial stiffness, and markedly low cardiorespiratory fitness levels are hallmark manifestations of the disease that contribute to the CVD burden. Despite advancements in blood pressure and lipid lowering pharmacological therapies, CVD remains markedly prevalent across the spectrum of CKD. This highlights a stagnation in effective clinical strategies to improve cardiovascular health and reinforces the critical need for adjuvant lifestyle strategies such as physical activity and exercise training to be incorporated into routine clinical care. This narrative review provides an overview of the known effects of exercise on vascular and cardiopulmonary function across the spectrum of CKD. The physiological mechanisms of vascular dysfunction that serve as exercise-specific therapeutic targets are highlighted and future perspectives are discussed.

The impact of cardiorespiratory fitness and physical workload on disability pension–a cohort study of Swedish men

ObjectiveUnderstanding the impact of physical capacity in combination with high physical workload could be beneficial for the prevention of health-related exits from work. Therefore, the aim of this study was to investigate the separate and combined effects of low cardiorespiratory fitness and high physical workload on disability pension (DP) due to any cause, musculoskeletal disorders (MSD), and cardiovascular diseases (CVD).MethodsA total of 279 353 men born between 1951 and 1961 were followed regarding DP between 2006 and 2020, ages 45–64. Cardiorespiratory fitness was assessed during military conscription, using an ergometer bicycle test. Physical workload was based on a job-exposure matrix (JEM) linked to occupational title in 2005. Cox regression models estimated separate and combined associations with DP.ResultsLow cardiorespiratory fitness and high physical workload were associated with increased risk of DP. For all cause DP, the fully adjusted hazard ratio and 95% confidence interval for those with low cardiorespiratory fitness was 1.38 (1.32–1.46) and for those with high physical workload 1.48 (1.39–1.57). For all cause and MSD DP, but not for CVD DP, the combination of low cardiorespiratory fitness and high physical workload resulted in higher risks than when adding the effect of the single exposures.ConclusionBoth low cardiorespiratory fitness in youth and later exposure to high physical workload were associated with an increased risk of DP, where workers with the combination of both low cardiorespiratory fitness and a high physical workload had the highest risks (all-cause and MSD DP).

Lower cardiorespiratory fitness is associated with left atrial structural, functional and electrical remodelling in patients with symptomatic atrial fibrillation

Abstract Background Preserved cardiorespiratory fitness (CRF) is associated with improved rhythm control in patients with symptomatic atrial fibrillation (AF). However, the pathophysiological features associated with low cardiorespiratory fitness are not well described. Purpose Evaluate the association between cardiorespiratory fitness and structural, functional and electroanatomical features of the left atrium (LA) amongst patients with symptomatic AF. Methods Consecutive patients with symptomatic paroxysmal or persistent AF undergoing AF ablation were recruited. CRF was assessed objectively by peak oxygen consumption (VO2peak) assessed during maximal cycle ergometry. Invasive assessment of LA remodelling involved direct assessment of resting LA pressures (LAP), LA stiffness during saline infusion and LA electrical function using high-density electroanatomical maps. Non-invasive assessment involved 2D transthoracic echocardiography at rest and during exercise. The association between VO2PEAK and atrial parameters were determined using multivariable linear regression models adjusted for age and sex. Results In total, 110 participants were recruited. Mean age was 63±11 and 74.5% of the cohort was male. In adjusted analyses, higher VO2PEAK was associated with lower mean LAP (p&amp;lt;0.001) and invasively assessed LA stiffness (p=0.005). On non-invasive testing, VO2PEAK was positively associated with left atrial emptying fraction (LAEF) (p=0.001) and reservoir strain (p&amp;lt;0.001) at rest. During exercise, VO2PEAK remained associated with LAEF (p&amp;lt;0.001) and LA reservoir strain (p=0.007). Higher VO2peak was positively associated with LA bipolar voltages (p=0.035) but not LA conduction velocities (p=0.131) or LA fractionation (p=0.452) Conclusions In patients with symptomatic AF, lower cardiorespiratory fitness is independently associated with extensive LA remodelling involving impaired LA haemodynamics, increased LA stiffness, LA mechanical dysfunction and LA electrical remodeling.

Cardiorespiratory Fitness and Risk of Cardiovascular Events and Mortality in Middle Age Patients without Known Cardiovascular Disease.

Low cardiorespiratory fitness is an established risk predictor for chronic non-communicable diseases. We aimed to investigate the prognostic significance of fitness level on the risk of major adverse cardiac events (MACE, the composite of myocardial infarction, stroke, or all-cause death), in a contemporary cohort of middle-aged subjects without cardiovascular disease. Retrospective analysis of patients aged 40-60 years without a history of cardiovascular disease. Degree of fitness was determined according to a graded, maximal treadmill exercise stress testing (EST) time achieved, classified into age- and sex-specific quintiles (Q), and categorized as low (Q1), moderate (Q2-Q4) or high (Q5) fitness groups. A multivariable Cox proportional hazard regression model was used to assess the association of fitness level with the risk of MACE. A total of 6836 patients were included, of which 44.5% were women, and the mean age was 52 years. Overall, 289 MACE events occurred during a median follow-up of 7 years. Level of fitness was inversely associated with the presence of cardiovascular risk factors. The multivariable adjusted hazard ratio (95% confidence interval) for MACE was 1.65 (1.12-2.44) and 2.17 (1.40-3.38) in those at moderate and low fitness levels, compared to the high-fitness group (reference), respectively. For each decrease of one metabolic equivalent (MET) unit achieved at peak exercise, the relative risk for MACE increased by 18%. The association between low fitness and MACE was not modified by other risk factors (P-for-interaction non-significant). Low fitness level, as captured by a maximal treadmill EST, is an independent risk predictor for MACE among middle-age individuals without known cardiovascular disease. The association of low fitness with high burden of cardiometabolic risk factors highlight the importance of lifestyle intervention in this patient population.