Poor Cardiorespiratory Fitness Research Articles

Machine Learning-Driven Phenogrouping and Cardiorespiratory Fitness Response in Metastatic Breast Cancer.

The magnitude of cardiorespiratory fitness (CRF) impairment during anticancer treatment and CRF response to aerobic exercise training (AT) are highly variable. The aim of this ancillary analysis was to leverage machine learning approaches to identify patients at high risk of impaired CRF and poor CRF response to AT. We evaluated heterogeneity in CRF among 64 women with metastatic breast cancer randomly assigned to 12 weeks of highly structured AT (n = 33) or control (n = 31). Unsupervised hierarchical cluster analyses were used to identify representative variables from multidimensional prerandomization (baseline) data, and to categorize patients into mutually exclusive subgroups (ie, phenogroups). Logistic and linear regression evaluated the association between phenogroups and impaired CRF (ie, ≤16 mL O2·kg-1·min-1) and CRF response. Baseline CRF ranged from 10.2 to 38.8 mL O2·kg-1·min-1; CRF response ranged from -15.7 to 4.1 mL O2·kg-1·min-1. Of the n = 120 candidate baseline variables, n = 32 representative variables were identified. Patients were categorized into two phenogroups. Compared with phenogroup 1 (n = 27), phenogroup 2 (n = 37) contained a higher number of patients with none or >three lines of previous anticancer therapy for metastatic disease and had lower resting left ventricular systolic and diastolic function, cardiac output reserve, hematocrit, lymphocyte count, patient-reported outcomes, and CRF (P < .05) at baseline. Among patients allocated to AT (phenogroup 1, n = 12; 44%; phenogroup 2, n = 21; 57%), CRF response (-1.94 ± 3.80 mL O2·kg-1·min-1 v 0.70 ± 2.22 mL O2·kg-1·min-1) was blunted in phenogroup 2 compared with phenogroup 1. Phenotypic clustering identified two subgroups with unique baseline characteristics and CRF outcomes. The identification of CRF phenogroups could help improve cardiovascular risk stratification and guide investigation of targeted exercise interventions among patients with cancer.

The prognostic role of cardiopulmonary exercise testing in obesity.

Poor cardiorespiratory fitness has been suggested to increase the risk of chronic diseases in obesity. We investigated the ability of key variables from cardiopulmonary exercise testing (CPET) to predict all-cause mortality in an obese cohort. The sample included 469 participants of both sexes (mean age 40 ± 13 years) who underwent a CPET for clinical reasons between 1 March 2009 and 1 December 2023. All-cause mortality was the prognostic endpoint. A receiver operating characteristic analysis was performed to establish optimal cut-points for CPET variables. Kaplan-Meier and Cox regression analyses were used to determine the association between CPET variables and all-cause mortality. There were 46 deaths during a mean follow-up period of 69 ± 48 months, resulting in an annual mortality rate of 2%. Despite the sample being made up of mostly women (70%), there were more deaths in men (18 vs. 6%, p < 0.001).The optimal thresholds for discrimination of survival were as follows: (a) peak oxygen uptake (pVO2) ≤16 mL/kg/min; (b) minute ventilation/carbon dioxide production (VE/VCO2) slope ≥31; (c) ventilatory power ≤5.8 mmHg; and (d) circulatory power ≤2980 mmHg/mL O2/min. Kaplan-Meier survival plots revealed a significant positive association between lower pVO2, circulatory power and ventilatory power values and survival (log-rank, p < 0.001) and higher mortality for men than women. Adjusted Cox regression models showed that a pVO2 ≤16 mL/kg/min had a 20-fold higher risk of mortality when compared with >16 mL/kg/min. Given the strong association of VO2, ventilatory efficiency, circulatory and ventilatory power with all-cause mortality, our findings support the notion that poorer cardiorespiratory fitness is associated with a poor prognosis in patients with obesity.

Stroke Incidence in Patients With Hypertension According to Cardiorespiratory Fitness.

Hypertension and physical inactivity are risk factors for stroke. The effect of cardiorespiratory fitness (CRF) on stroke risk in patients with hypertension has not been assessed. We evaluated stroke incidence in patients with hypertension according to CRF and changes in CRF. We included 483 379 patients with hypertension (mean age±SD; 59.4±9.0 years) and no evidence of unstable cardiovascular disease as indicated by a standardized exercise treadmill test. Patients were assigned to 5 age- and sex-specific CRF categories based on peak metabolic equivalents achieved at the initial exercise treadmill test and in 4 categories based on metabolic equivalent changes over time (n=110 576). Multivariable Cox models, adjusted for age, and comorbidities were used to estimate hazard ratios and 95% CIs for stroke risk. During a median follow-up of 10.6 (interquartile range, 6.6-14.6) years, 15 925 patients developed stroke with an average yearly rate of 3.1 events/1000 person-years. Stroke risk declined progressively with higher CRF and was 55% lower for the High-fit individuals (hazard ratio, 0.45 [95% CI, 0.42-0.48]) compared with the Least-fit. Similar associations were observed across the race, sex, and age spectra. Poor CRF was the strongest predictor of stroke risk of all comorbidities studied (hazard ratio, 2.24 [95% CI, 2.10-2.40]). Changes in CRF reflected inverse and proportional changes in stroke risk. Poor CRF carried a greater risk than any of the cardiac risk factors in patients with hypertension, regardless of age, race, or sex. The lower stroke risk associated with improved CRF suggests that increasing physical activity, even later in life, may reduce stroke risk.

Comparison of cardiorespiratory fitness levels between wearing and not wearing masks in physiotherapy students

Background: Masks, devices used to cover the face, nose, and mouth area to prevent the transmission of viruses, bacteria, diseases, and air pollution, have become a topic of pros and cons among the public regarding their impact on cardiorespiratory fitness during physical activity, as some claim that masks decrease airflow to the lungs thus reducing oxygen in the blood and muscles which makes activity more difficult, while other studies have shown no difference in cardiorespiratory fitness values with or without masks. The purpose of this study was to determine the difference in cardiorespiratory fitness levels when wearing a mask and not wearing a mask in physiotherapy students. Methods: This study used an analytical observational design with a one-group pre-post test design and a consecutive sampling technique involving 35 physiotherapy students from the Faculty of Medicine, Universitas Udayana. This research was conducted at the Physiotherapy Building, Faculty of Medicine, Universitas Udayana, in June 2023. The inclusion criteria included physiotherapy students aged ≥ 18 with normal vital signs who used a 3-ply surgical mask. The exclusion criteria were students with a history of respiratory problems and those who did not use a 3-ply surgical mask. Cardiorespiratory fitness was measured using the Harvard step test. Results: This study showed that the research subjects were dominated by students with poor cardiorespiratory fitness when wearing a mask or not wearing a mask, namely 35 students (100%). Conclusion: There was no significant difference in cardiorespiratory fitness levels between mask wearers and non-wearers, with a p-value of 0.180 (&gt;0.05).

Effects of Exercise Rehabilitation on Cardiorespiratory Fitness in Long-COVID-19 Survivors: A Meta-Analysis.

Background: Poor cardiorespiratory fitness poses the highest risk of mortality. Long-COVID-19 survivors exhibit a reduced cardiorespiratory fitness (CRF). While exercise rehabilitation, such as cardiopulmonary exercise, is used for long-COVID-19 survivors, the effects of exercise on CRF in this population remain inconclusive. In this study, we aim to systematically summarise and synthesise whether exercise rehabilitation improves CRF among long-COVID-19 survivors. Methods: A comprehensive search was performed through PubMed, CINAHL, Embase, Scopus, and the Cochrane Library (since their inception to November 2023) and study reference lists. Studies presenting the effects of exercise rehabilitation on CRF (peak oxygen consumption (VO2peak) and six-minute walk distance (6MWD)) in long-COVID-19 survivors were identified. The standardised mean difference (SMD), mean difference (MD), and 95% confidence interval (CI) were used for analyses. The certainty of evidence was measured using a Grading of Recommendation Assessment, Development and Evaluation approach. Results: Twelve eligible studies (five RCTs and seven non-RCTs) with 682 participants were analysed. The meta-analysis showed significantly improved 6MWDs (MD 76.47, 95% CI 59.19-93.71, low certainty) and significantly greater 6MWDs (SMD 0.85, 95% CI 0.11-1.59, very low certainty) in the exercise rehabilitation group compared to the control group. A significantly improved 6MWD was found in subgroups of young to middle-aged adults and subgroups of patients who undertook aerobic exercise combined with resistance and respiratory exercise and centre-based training programs. Conclusions: Exercise rehabilitation is effective for improving CRF, as measured by the 6MWD in long-COVID-19 survivors. Improvements are likely to be more pronounced in specific subgroups of young to middle-aged adults and patients undertaking aerobic exercise combined with resistance and respiratory exercise and centre-based training programs. However, recommendations for clinical practice are limited due to the very low evidence certainty.

Longitudinal Patterns of Systolic Blood Pressure, Diastolic Blood Pressure, Cardiorespiratory Fitness, and Their Association With Dementia Risk: The HUNT Study.

High blood pressure and poor cardiorespiratory fitness are independent risk factors for dementia. However, few studies have examined if combined longitudinal patterns of these modifiable risk factors are associated with dementia risk. In this prospective cohort study, we used data from the population-based Trøndelag Health (HUNT) Study, Norway. We applied group-based multidimensional trajectory modeling to identify age-specific multidimensional trajectories of SBP, DBP, and estimated cardiorespiratory fitness across 3 surveys (HUNT1, 1984-1986 to HUNT3, 2006-2008). Dementia was diagnosed in the HUNT4 70+ substudy in 2017-2019. We used multivariate logistic regression to estimate odds ratios (ORs) and risk differences (RDs) of dementia. In total, 7594 participants (54.9% women) were included, with a mean age of 44.7 (SD 6.3) years at HUNT1. Dementia was diagnosed in 1062 (14.0%) participants. We identified 2 multidimensional trajectories throughout adulthood within 3 age groups: one with higher systolic blood pressure (SBP) and diastolic blood pressure (DBP), and lower estimated cardiorespiratory fitness (the poorer group), and one with lower SBP and DBP, and higher cardiorespiratory fitness (the better group). After adjustment for sex, apolipoprotein E ε4 status, education, marital status, and diabetes, the better group had consistently lower risk of dementia in all age groups with the lowest OR in the middle-aged group of 0.63 (95% confidence intervals [95% CI]: 0.51, 0.78) with corresponding RD of -0.07 (95% CI: -0.10, -0.04). Having a beneficial multidimensional trajectory of SBP, DBP, and cardiorespiratory fitness in adulthood was associated with reduced dementia risk. Aiming for optimal SBP, DBP, and estimated cardiorespiratory fitness throughout adulthood may reduce dementia risk.

Incongruence between Cardiorespiratory Fitness and Subjective Reports of Physical Activity in Multiple Sclerosis: A Focus on Sex Differences.

The link between moderate- to vigorous-intensity physical activity (MVPA) and cardiorespiratory fitness in individuals with multiple sclerosis (MS) remains unclear. This study examined the relationship between self-reported MVPA and objectively assessed cardiorespiratory fitness, emphasizing sex differences. 107 adults with MS (77 females), aged (mean ± standard deviation) 47.2 ± 10.2 years, were recruited from a local MS clinic. Fitness was measured as maximal oxygen uptake (V̇O2max) during a graded maximal exercise test using a recumbent stepper. MVPA (24-hour recall) was estimated as the duration of activities ≥ 3 MET (metabolic equivalent of task). MET-minutes were calculated by multiplying MET by duration. We explored sex differences in self-reported MVPA, cardiorespiratory fitness, and disability; examined sex differences in associations between these variables; and investigated whether MET-minutes of MVPA predicted V̇O2max in females and males. Mean V̇O2max was 24.79 mL·kg-1·min-1, indicating poor cardiorespiratory fitness levels, despite high levels of self-reported MVPA (mean = 412.5 MET-minutes). Fifty-three percent of males and 40% of females had V̇O2max levels below the 20th age- and sex-standardized population percentile, indicating poor cardiorespiratory fitness. There were statistically significant associations between MVPA and V̇O2max (Rho = 0.27, p = .01), as well as disability and V̇O2max (Rho = -0.35, p = .02), in females but not males. A regression model using sex, age, body mass, disability, and MVPA to estimate V̇O2max was valid in predicting V̇O2max values that were statistically equivalent to those measured in the laboratory in females but not males. However, the inclusion of MVPA did not add to the predictive value of this equation. Despite reporting high levels of MVPA, people with MS had poor cardiorespiratory fitness. MVPA, fitness, and disability were associated in females only, indicating that sex differences should be considered in fitness appraisal. Self-reported MVPA did not predict fitness, suggesting 24-hour recall may not be representative of true activity or fitness levels in persons with MS. Future work should examine sex differences in associations between MVPA and fitness using objective measures such as accelerometry.

The Impact of Body Composition on Cardiorespiratory Fitness in Adult Females.

This study investigates the impact of body composition on cardiorespiratory fitness (CRF) in adult females, focusing on factors such as maximal oxygen uptake (VO2 max). It also emphasizes the importance of maintaining a physically active lifestyle for achieving CRF. Previous research links CRF to protection against metabolic syndrome. To investigate the impact of body composition as specified by body mass index (BMI), fat-free mass (FFM), fat mass (FM), and basal metabolic rates (BMRs) on CRF in adult females. Adult females aged 19-24 participated in this prospective cross-sectional experimental study (n=110). The study excluded those with specific health conditions. Anthropometric measurements, bio-impedance analysis, and a Balke treadmill test were conducted to assess VO2 max and, hence, theCRF. Nutrient intake was assessed, and energy requirements were calculated. The data were analyzed using Statistical Product and Service Solutions (SPSS, version 21; IBM SPSS Statistics for Windows, Armonk, NY). The test statistics deployed were mean (± SD), ANOVA, Pearson's correlation coefficient, post-hoc Bonferroni test, and regression analysis. The study revealed significant differences in anthropometry among BMI categories. Energy intake showed no significant variation. Body mass distribution, BMRs, and vital signs significantly differed among BMI groups. Most participants exhibited poor CRF; a negative correlation between BMI and VO2 max was observed. Body compositions, particularly BMI and FFM, body fat percentage, and BMR, influence CRF in young adult females. Poor CRF was prevalent among participants, indicating a potential impact on cardiovascular health. The findings underline the importance of addressing lifestyle factors in promoting better cardiorespiratory health among young adult females.

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.

Long-term impact of SARS-CoV-2 infection on cardiorespiratory fitness: a meta-analysis.

Despite surviving Coronavirus disease 2019 (COVID-19), its long-term impact is of concern. Low cardiorespiratory fitness is a strong predictor of all-cause mortality, and likely affected by multisystem impairments following COVID-19 infection. Accumulating evidence has identified the impact of COVID-19 on cardiorespiratory fitness level. However, the findings have been controversial. Conclusive evidence is still needed. This review aimed to systematically summarize and synthesize whether the SARS-CoV-2 infection diminishes cardiorespiratory fitness in COVID-19 survivors. The study design was a systematic review and meta-analysis. A search was carried out using PubMed, CINAHL, Scopus, Embase and the Cochrane Library, together with reference lists (searching from their inception to January 2023). Observational studies investigating the impact of COVID-19 on outcomes relevant to cardiorespiratory fitness (i.e., peak oxygen uptake) were included. Weighted mean difference (WMD) and 95% confidence interval (CI) were used to identify a pooled effect estimate. Use of a random effects model was considered as the main method. Grading of Recommendation Assessment, Development and Evaluation approach was employed to determine the certainty of evidence. This meta-analysis was registered with PROSPERO (registration number: CRD42023393108). Seven eligible studies (4 cross-sectional, 2 cohort, and 1 case-control studies) involving 4,773 participants were included in this meta-analysis. A pooled effect estimates showed that patients in the surviving COVID-19 group had a significant reduction in peak oxygen uptake when compared to their counterparts in the non-COVID-19 group (WMD -6.70, 95%CI -9.34 to -4.06, low certainty). A subgroup analysis by age found that COVID-19 survivors in the young- to middle-aged and middle- to older-aged subgroups had significant reductions in peak oxygen uptake when compared to their counterparts in the non-COVID-19 group (WMD -5.31, 95%CI -7.69 to -2.94, low certainty; WMD -15.63, 95%CI -28.50 to -2.75, very low certainty, respectively). Subgroup analyses by symptom found that patients with moderate to severe symptoms in the surviving COVID-19 group had significantly lower peak oxygen uptake than their counterparts in the non-COVID-19 group (WMD -15.63, 95%CI -28.50 to -2.75, very low certainty). The current meta-analysis concluded that patients in the COVID-19 survivors had poorer cardiorespiratory fitness than their counterparts in the non-COVID-19 group, but there is considerable uncertainty of evidence. Poorer cardiorespiratory fitness is likely to be more pronounced in COVID-19 survivors who are getting older and had severe symptoms, but it is uncertain whether such finding has a valuable in clinical context. https://www.crd.york.ac.uk/PROSPERO/, CRD42023393108.

Poor cardiorespiratory fitness in first year medical students at a South African University

ABSTRACT The personal health behaviours, including physical activity, of healthcare professionals influence their counselling practices as they relate to non-communicable diseases (NCDs). However, despite the importance of producing healthy, physically active graduates, there are limited data on the physical fitness of future healthcare professionals. This cross-sectional observational study determined the prevalence of below-average fitness in the four components of fitness in first-year university medical students. 152 participants (46 male, 106 female, 20.16 ± 2.69 years) completed cardiorespiratory fitness tests (submaximal step test), flexibility (sit-and-reach test), muscle strength (handgrip), and muscle endurance tests (sit-ups, push-ups). Sex differences were reported using one-way ANOVA or Chi square test and significance was set at p < 0.05. The prevalence (%) of below-average fitness was 69.54% for cardiorespiratory, 25.66% for handgrip strength, 65.79% for sit-ups, 23.03% for push-ups and 7.24% for flexibility. Physical fitness parameters (mean±standard deviation (SD)) were compared between sexes, where it was found that females were more flexible than males (40.61 ± 8.40 cm vs 36.70 ± 9.31 cm, p = 0.012). Males had better handgrip strength (88.96 ± 12.04 kg vs 59.34 ± 10.36 kg, p < 0.001), muscle endurance sit-ups (33.46 ± 9.04 vs 24.48 ± 12.18, p < 0.001) and push-ups (30.28 ± 13.95 vs 24.27 ± 12.35, p = 0.009). First-year medical students have poor physical fitness, notably cardiorespiratory fitness and muscle strength, which are important markers for NCD risk assessment. Tertiary institutions training healthcare professionals should consider developing interventions to improve students’ physical fitness thereby influencing their health, wellbeing, academic performance and future counselling practices.

Cardiorespiratory fitness in women after severe pre-eclampsia

ABSTRACT Aims To objectively study cardiorespiratory fitness (CRF) and physical activity (PA) and to evaluate limiting factors of exercise intolerance associated with poor CRF after severe pre-eclampsia. Methods In this single-centre, cross-sectional study, CRF was measured as peak oxygen uptake (VO2peak) during a cardiopulmonary exercise test (CPET) on a treadmill in women 7 years after severe pre-eclampsia. Ninety-six patients and 65 controls were eligible to participate. Cardiac output (CO) was measured by impedance cardiography. PA was measured using accelerometers. Results In 62 patients and 35 controls (mean age 40 ± 3 years), the VO2peak (in mL·kg–1·min–1) values were 31.4 ± 7.2 and 39.1 ± 5.4, respectively (p<0.01). In the patients, the COpeak was (9.6 L·min-1), 16% lower compared to controls (p<0.01). Twelve patients (19%) had a cardiac limitation to CPET. Twenty-three (37%) patients and one (3%) control were classed as unfit, with no cardiopulmonary limitations. The patients demonstrated 25% lower PA level (in counts per minute; p<0.01) and 14% more time being sedentary (p<0.01), compared with the controls. Twenty-one patients (34%) compared with four (17%) controls did not meet the World Health Organization’s recommendations for PA (p=0.02). Body mass index and PA level accounted for 65% of the variability in VO2peak. Conclusion Significantly lower CRF and PA levels were found in patients on long-term follow-up after severe pre-eclampsia. CPET identified cardiovascular limitations in one third of patients. One third appeared unfit, with adiposity and lower PA levels. These findings highlight the need for clinical follow-up and exercise interventions after severe pre-eclampsia.

Right Ventricular Dysfunction and Exercise Impairment in Patients with Heart Failure, Insulin Resistance, and Diabetes Mellitus: Insights from the T.O.S.CA. Registry (Cardiovascular Diabetology 2022).

Insulin resistance (IR) and type 2 diabetes mellitus (T2D) are known to affect the progression of chronic heart failure (CHF), but little evidence exists about the impact of IR and T2D on right ventricular dysfunction and exercise tolerance. Insights from the T.O.S.C.A. Registry: Echocardiographic hallmarks and cardiopulmonary exercise test (CPET) results were evaluated at baseline and after an average time of 36 months. T2D patients exhibited a greater intraventricular septum (IVS) thickness (11 ± 2 mm, 10 ± 2 mm, 10 ± 2 mm, in T2D, IR, and EU, respectively; p<.05) and LV wall thickness (0.34 ± 0.1, 0.32 ± 0.1, and 0.32 ± 0.1, in T2D, IR, and EU, respectively; p<.05). Moreover, T2D patients exhibited worse LV filling dynamics with larger left atrial volume index compared to IR and EU. Right ventricle dysfunction, expressed as a lower TAPSE/PASP ratio, was found in T2D [0.52(0.32-0.72)] than in EU and IR [0.60(0.30-0.90); p<.05]. T2D patients showed a significantly lower VO2 max peak when compared to IR and EU patients (15.8 ± 3.8 vs. 16.5 ± 4.3 vs. 18.4 ± 4.3 ml/Kg/min; p<.003), with an inverse relationship between the HOMAIR classes and VO2 max. Right ventricle structure and function deteriorated more rapidly in T2D, as suggested by more relevant deterioration in TAPSE/PASP ratio (-10% in EU patients, -14% in IR patients, -21% in T2D; p<.05). The study findings suggest that the right ventricle structure, function, and cardiopulmonary performance deteriorate with IR and, more evidently, due to chronic exposure to hyperglycemia in T2D. Impaired exercise tolerance, poor cardiorespiratory fitness, diastolic dysfunction, and left atrial enlargement predispose patients to poor quality of life, suboptimal adherence to physical activity, and an overall increase in the risk of all-cause and cardiovascular mortality. In addition, chronic hyperglycemia accelerates the progression of these alterations, especially in patients with poor glycemic control over time. Highly selective and even more non-selective sodium glucose transporter type 2 inhibitors and glucagon-like peptide 1 receptor agonists should be considered as the first-line therapy for improving CV outcomes in T2D and CHF. Further studies are needed to understand the role of these molecules in treating pre-clinical conditions, such as IR and metabolic syndrome.

Association between cardiorespiratory fitness level and insulin resistance in adolescents with various obesity categories.

An association between cardiorespiratory fitness (CRF) and insulin resistance in obese adolescents, especially in those with various obesity categories, has not been systematically studied. There is a lack of knowledge about the effects of CRF on insulin resistance in severely obese adolescents, despite their continuous rise. To investigate the association between CRF and insulin resistance in obese adolescents, with special emphasis on severely obese adolescents. We performed a prospective, cross-sectional study that included 200 pubertal adolescents, 10 years to 18 years of age, who were referred to a tertiary care center due to obesity. According to body mass index (BMI), adolescents were classified as mildly obese (BMI 100% to 120% of the 95th percentile for age and sex) or severely obese (BMI ≥ 120% of the 95th percentile for age and sex or ≥ 35 kg/m2, whichever was lower). Participant body composition was assessed by bioelectrical impedance analysis. A homeostatic model assessment of insulin resistance (HOMA-IR) was calculated. Maximal oxygen uptake (VO2max) was determined from submaximal treadmill exercise test. CRF was expressed as VO2max scaled by total body weight (TBW) (mL/min/kg TBW) or by fat free mass (FFM) (mL/min/kg FFM), and then categorized as poor, intermediate, or good, according to VO2max terciles. Data were analyzed by statistical software package SPSS (IBM SPSS Statistics for Windows, Version 24.0). P < 0.05 was considered statistically significant. A weak negative correlation between CRF and HOMA-IR was found [Spearman's rank correlation coefficient (rs) = -0.28, P < 0.01 for CRFTBW; (rs) = -0.21, P < 0.01 for CRFFFM]. One-way analysis of variance (ANOVA) revealed a significant main effect of CRF on HOMA-IR [F(2200) = 6.840, P = 0.001 for CRFTBW; F(2200) = 3.883, P = 0.022 for CRFFFM]. Subsequent analyses showed that obese adolescents with poor CRF had higher HOMA-IR than obese adolescents with good CRF (P = 0.001 for CRFTBW; P = 0.018 for CRFFFM). Two-way ANOVA with Bonferroni correction confirmed significant effect of interaction of CRF level and obesity category on HOMA-IR [F(2200) = 3.292, P = 0.039 for CRFTBW]. Severely obese adolescents had higher HOMA-IR than those who were mildly obese, with either good or poor CRF. However, HOMA-IR did not differ between severely obese adolescents with good and mildly obese adolescents with poor CRF. CRF is an important determinant of insulin resistance in obese adolescents, regardless of obesity category. Therefore, CRF assessment should be a part of diagnostic procedure, and its improvement should be a therapeutic goal.

Physical Activity Protocols in Non-Alcoholic Fatty Liver Disease Management: A Systematic Review of Randomized Clinical Trials and Animal Models.

Non-alcoholic fatty liver disease (NAFLD) is closely associated with other metabolic disease and cardiovascular disease. Regular exercise reduces hepatic fat content and could be the first-line treatment in the management of NAFLD. This review aims to summarize the current evidence of the beneficial effects of exercise training and identify the molecular pathways involved in the response to exercise to define their role in the resolution of NAFLD both in animal and human studies. According to the inclusion criteria, 43 animal studies and 14 RCTs were included in this systematic review. Several exercise modalities were demonstrated to have a positive effect on liver function. Physical activity showed a strong association with improvement in inflammation, and reduction in steatohepatitis and fibrosis in experimental models. Furthermore, both aerobic and resistance exercise in human studies were demonstrated to reduce liver fat, and to improve insulin resistance and blood lipids, regardless of weight loss, although aerobic exercises may be more effective. Resistance exercise is more feasible for patients with NAFLD with poor cardiorespiratory fitness. More effort and awareness should be dedicated to encouraging NAFLD patients to adopt an active lifestyle and benefit from it its effects in order to reduce this growing public health problem.

Cardiorespiratory fitness and cardiovascular risk among in-patients with depression compared to healthy controls.

Compared to the general population, individuals with depression have an increased risk for cardiovascular diseases. Nevertheless, little is known so far whether cardiorespiratory fitness (CRF) moderates this relationship. Therefore, we examined whether common physiological cardiovascular risk factors differ between patients with depression and healthy (non-depressed) controls, whether patients and controls differ in CRF, and whether higher CRF is associated with a lower cardiovascular risk in both patients and healthy controls. Additionally, we examined whether within the patient sample, cardiovascular risk factors differ between patients with mild, moderate and severe depression, and whether the relationship between symptom severity and cardiovascular risk is moderated by patients' CRF levels. Data from a multi-centric, two-arm randomized controlled trial (RCT) was analyzed, including 210 patients (F32, single episode: n = 72, F33, recurrent major depression: n = 135, F31-II, bipolar type II: n = 3) and 125 healthy controls. Waist circumference, body mass index, body fat, blood pressure, cholesterol levels, triglycerides, and blood glucose were considered as cardiovascular risk markers. CRF was assessed with a submaximal ergometer test. Differences between groups were examined via χ2-tests and (multivariate) analyses of covariance. Compared to healthy controls, patients with depression had a higher cardiovascular risk as evident from about half of the examined indicators. In the total sample, participants with good CRF had more favourable scores across nearly all risk markers than counterparts with poor CRF. For most variables, no interaction occurred between group and fitness, indicating that in patients and controls, similar differences existed between participants with poor and good CRF. Few differences in risk markers were found between patients with mild, moderate and severe depression, and no interaction occurred between depression severity and CRF. Patients with depression and healthy controls differ in several cardiovascular risk markers, putting patients at increased risk for CVDs. In contrast, people with good CRF show more favourable cardiovascular risk scores, a relationship which was observed in both healthy controls and patients with depression. Physical health of psychiatric patients should receive the clinical attention that it deserves. Lifestyle interventions targeting healthy diet and/or physical activity are recommended as a physically active and healthy lifestyle contributes equally to patients' mental well-being and cardiovascular health.

Poor cardiorespiratory fitness may be an indicator of more severe liver inflammation in non-alcoholic fatty liver disease patients

IntroductionNon-alcoholic fatty liver disease (NAFLD) is related to cardiovascular disease. Cardiorespiratory fitness (CRF) is an important indicator of cardiovascular health. Therefore, we aimed to evaluate the CRF of NAFLD patients. MethodsCross-sectional study, including 32 patients with biopsy-proved NAFLD. The patients underwent ergometric test (ET) and six-minute walk test (6MWT) to determine CRF. The test results were compared to disease parameters and with each other. ResultsConsidering the ET, 20 (62.5%) patients had very poor or poor CRF, and in 12 (37.5%), it was regular or good. In the 6MWT, 13 (40.6%) individuals had poor CRF, in 12 (37.5%), it was very poor, and in seven (21.9%), regular. NAFLD activity score (NAS) ≥5 was observed in 12 (37.5%) individuals. Twelve (37.5%) patients were sedentary, 11 (34.4%), insufficiently active, and nine (28.1%), active. Obesity and liver inflammation on biopsy were associated with very poor/poor CRF. NAS ≥5 and sedentary lifestyle were independently associated with very poor/poor CRF by ET. Although mean VO2max values determined by both tests were similar, no correlation of VO2max determined by ET and 6MWT was observed, as occurred for the distance walked in 6MWT and values of metabolic equivalent (MET) determined by ET. There was no reproducibility between CRF determined by ET and 6MWT. ConclusionMost NAFLD patients had very poor or poor CRF. Severe liver injury (NAS ≥5) and sedentary lifestyle were independently associated with very poor/poor fitness, according to ET. No reproducibility was observed between the CRF defined by ET and 6MWT.

#6919 CARDIORESPIRATORY FITNESS AND MORTALITY RISK IN PATIENTS RECEIVING HEMODIALYSIS: A PROSPECTIVE COHORT

Abstract Background and Aims Kidney failure reduces life expectancy by one-third compared with the general population, and cardiovascular complications and poor cardiorespiratory fitness (CRF) are the main causes. We aimed to evaluate the association between severe CRF and all-cause mortality risk in HD patients. Method This observational prospective cohort study followed-up patients receiving HD from August 2015 until March 2022. Cardiorespiratory fitness was evaluated through the cardiopulmonary exercise test and the peak of oxygen uptake (VO2peak) value was used to determine severe CRF (&amp;lt;15 mL·kg−1·min−1). Cox regression and Univariate Kaplan-Meier evaluated its association with mortality risk and survival rate. Results Forty-eight patients were followed-up for a median of 33.0 [14.3 – 49.3] months. A total of 26 patients had severe CRF. During the follow-up period, 11 patients (22.92%) experienced all-cause mortality. From these, eight (30.8%) had severe CRF. Even so, severe CRF was not associated with crude death rates for patients stratified by CRF levels (p = 0.189), neither in unadjusted (HR 2.35; CI 95% 0.61−9.15) and adjusted (HR 1.29; CI 95% 0.30−5.56) Cox proportional hazard models. As a continuous variable, each mL·kg−1·min−1 increase in VO2peak was not associated with mortality risk (HR 0.94; CI 95% 0.79−1.11). Univariate Kaplan-Meier analysis showed that severe CRF patients did not have significantly worse survival rates than those with mild-moderate CRF (p = 0.186). Conclusion Our findings indicated that severe CRF was not associated with all-cause mortality in patients receiving HD. Despite severe CRF being prevalent, larger cohort studies are needed to establish strong conclusions on its association with all-cause mortality.

#5045 CARDIORESPIRATORY FITNESS IN KIDNEY TRANSPLANT RECIPIENTS: A CASE-CONTROL STUDY AND INITIAL REVIEW OF THE EFFECTS OF A HOME-BASED EXERCISE PROGRAMME

Abstract Background and Aims Kidney transplant recipients (KTRs) have an increased burden of cardiovascular disease (CVD) due to clustering of traditional and non-traditional risk factors. Poor cardiorespiratory fitness (CRF) is linked to higher levels of morbidity and mortality. Cardiorespiratory fitness is a significant predictor of 7-year risk of mortality, with each 1 ml/kg/min increase in VO2 associated with a 1% decrease in risk of mortality.[1] Although KTRs have higher CRF than patients with kidney failure, performance compared to the general population has not been quantified. Neither has the link between CRF and physical function. We assessed differences in CRF between KTRs and healthy volunteers in a case-control study. We then explored relationships between CRF and physical function and possible effects of a 12-week structured home-based exercise programme in KTRs. Method Case-control: 20 KTRs (10 male; age 61.2 ±8.1 years; body mass 84.1 ±19.9 kg) and 20 healthy volunteers (10 male; age 61.9 ±7.7 years; body mass 76.7 ±18.1 kg) completed a continuous ramp cardiopulmonary exercise test (CPET) to volitional exhaustion on a cycle ergometer. CPET variables were compared between groups using independent samples t-tests. Thirteen KTRs (6 male; age 47.8 ±15.9 years; eGFR 64.6 ±19.1 ml/min/1.73 m2), to date, have completed a 12-week structured, combined aerobic and resistance, home-based exercise programme as part of a pilot randomised controlled trial.[2] Bivariate correlations were used to explore the association between cardiorespiratory fitness and physical function measures (sit-to-stand 60 [STS60], timed up and go [TUAG], gait speed [GS] and handgrip strength [HGS]). Paired samples t-tests were used to compare pre- and post-intervention variables. Results Case-control: Cardiorespiratory fitness (VO2 peak) was lower in KTRs (18.4±5.2 mL/kg/min) than in healthy volunteers (24.3 ±5.9 mL/kg/min), a difference of 5.9 mL/kg/min (95% CI, 2.4-9.5), t(38) = 3.35, p &amp;lt;.001. Peak heart rate achieved was higher in healthy volunteers than in KTRs (154 v 136 bpm; p = .009). Maximum power achieved was higher in healthy volunteers but did not reach significance (147 v 116 W; p = .052). There was a positive correlation between STS60 and VO2 peak (r = .652, p = .016) and between GS and VO2 peak (r = .583, p = .037). There was a negative correlation between TUAG and VO2 peak (r = .-.664, p = .013) and no association between HGS and VO2 peak. There was an increase in VO2 peak after the 12-week exercise programme (19.4±4.5 mL/kg/min to 20.4±5.0 mL/kg/min, p = .018). Maximum power achieved did not change post-intervention (118 v 121 W; p = .423). STS60 was the only physical function test to improve post-intervention (24 v 27; p = .010). Conclusion Cardiorespiratory fitness in KTRs is significantly impaired compared to healthy control subjects. In KTRs, aerobic fitness assessed with VO2 peak correlated with field tests assessing physical function. Initial findings suggest that CRF may improve following a structured, home-based programme of exercise, but these data need confirming in larger studies and will be assessed in the final analysis of this pilot randomised trial.

Sex differences in the change in cardiorespiratory fitness and quality of life following exercise training in adults with atrial fibrillation: a systematic review and meta-analysis

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): University of Ottawa Heart Institute. Patients with atrial fibrillation (AF) often have poor cardiorespiratory fitness (CRF), quality of life (QoL) and mental health. Improving CRF through exercise training is an important AF management target associated with lower hospitalization and mortality rates. Emerging research indicates smaller CRF increases in females than males following exercise training. Yet, this has not been examined in those with AF. The primary aim was to compare changes in CRF (estimated or directly measured as peak oxygen consumption [VO2peak, mL O2/kg/min]) following exercise training between females and males with AF. We hypothesized that females would experience smaller CRF improvements. Secondary aims compared changes in functional capacity (6-minute walk test [6MWT] distance), QoL (SF-36), anthropometric and hemodynamic measures, and anxiety and depression (Hospital Anxiety and Depression Scale). Methods This review adhered to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines and was registered with PROSPERO (#CRD42022302310). Five electronic bibliographic databases were searched to identify published and unpublished studies up to January 2022, with prospective cohort and experimental designs, implementing exercise training of any form ≥4 weeks, in adults with AF. When eligible studies did not segregate results by sex, authors were contacted to obtain their sex-specific data. Random-effects meta-analyses were performed to synthesize the measures of effect (i.e. mean difference [MD] in the changes between sexes following exercise). Results Our search identified 9,398 studies. Sex-specific data were obtained from 18/60 eligible studies (see Table 1), with 868 participants enrolled in an exercise training program (29% females, F: 69±7, M: 66±8 years old). Exercise interventions lasted between 6 weeks to 1 year and used mainly aerobic training of light to high intensity, 2 to 5 days/week. The change in VO2peak did not differ between sexes (MD=+0.25, 95% CI=−1.13 to +1.62 mL O2/kg/min, p=0.724; I²=33%, see Figure 1). There were no differences in changes in functional capacity (MD=−7.11, 95% CI=−22.56 to +8.34 m, p=0.367; I²=66%); Physical Component Summary (MD=+0.82, 95% CI=−1.72 to +3.36 points, p=0.526; I²=49%) and Mental Component Summary (MD=+1.03, 95% CI=−1.68 to +3.75 points, p=0.456; I²=46%) scores of the SF-36; body mass index (MD=−0.13, 95% CI=−0.94 to +0.68 kg/m², p=0.756; I²=0%); anxiety (MD=+0.22, 95% CI=−1.33 to +1.77 points, p=0.782; I²=39%) and depression (MD=-0.01, 95% CI=−1.64 to +1.63 points, p=0.995; I²=60%). Smaller reductions in SBP were found in females than males (MD=+3.11, 95% CI=0.14 to 6.09 mmHg, p=0.040, I²=42%). Conclusions This review addressed the lack of sex-based analyses in previous exercise studies in AF. We did not observe smaller changes in CRF in females. However, the underrepresentation of females in research continues to hinder establishing clear conclusions in sex-specific research.