Better Cardiorespiratory Fitness Defined as VO2max Increases the Chance of Partial Clinical Remission and Prolongs Remission Duration in People with Newly Diagnosed Type 1 Diabetes.

Introduction: An essential process affecting the course of type 1 diabetes (DM1) is the appearance and duration of clinical remission. One of the most important factors promoting the occurrence of remission is physical activity, due to increased activity of antioxidants, reduces insulin resistance and improves glucose transport. Maximal oxygen capacity (VO2max) is an objective measure of the body's aerobic capacity. To assess VO2max, oxygen uptake should be measured directly during the exercise test. The aim of the study was to evaluate the physical capacity in adults with DM1 and its relationship with the occurrence of partial clinical remission (pCR) during 2 years follow-up. Methods: The pCR was assessed by the following mathematical formula: A1c (%) + [4 × insulin dose (U/kg/d)]. The result ⩽9 indicates pCR. VO2max was assessed between 6th and 24th month of diabetes duration using an ergospirometer (COSMED K5 System), during an exercise test carried out on a cycloergometer (RAMP incremental exercise test). Results: The study group consisted of 32 adults with DM1. People with pCR were proved to have higher VO2max level [36.0 (33.0-41.5) vs 30.9 (26.5-34.4) ml/min/kg, P = .009. Univariate and multivariate regression confirmed a significant association between VO2max and presence of pCR [AOR 1.26 (1.05-1.52), P = .015]. Duration of remission was longer among group with higher VO2max results [15 (9-24) vs 9 (0-12) months, P = .043]. The positive relationship was observed between diabetes duration and VO2max (rs = 0.484, P = .005). Multivariate linear regression confirms a significant association between remission duration and VO2max (ml/min/kg) (ß = 0.595, P = .002). Conclusion: The higher VO2max, the better chance of partial clinical remission at 2 years of DM1 and longer duration of remission.

Better cardiorespiratory fitness increases the chance of partial clinical remission and prolongs remission duration in people with newly diagnosed type 1 diabetes. Introduction An essential process affecting the course of type 1 diabetes (DM1) is the appearance and duration of clinical remission. One of the most important factors promoting the occurrence of remission is physical activity, due to increased activity of antioxidants, reduces insulin resistance and improves glucose transport. Maximal oxygen capacity (VO₂max) is an objective measure of the body's aerobic capacity. To assess VO₂max, oxygen uptake should be measured directly during the exercise test. The aim of the study was to evaluate the physical capacity in adults with DM1 and its relationship with the occurrence of partial clinical remission (pCR) during 2 years follow-up. Methods The pCR was assessed by the following mathematical formula: A1c (%) + [4 × insulin dose (U/kg/d)]. The result ⩽9 indicates pCR. VO₂max was assessed between 6th and 24th month of diabetes duration using an ergospirometer (COSMED K5 System), during an exercise test carried out on a cycloergometer (RAMP incremental exercise test). Results The study group consisted of 32 adults with DM1. People with pCR were proved to have higher VO₂max level [36.0 (33.0-41.5) vs 30.9 (26.5-34.4) ml/min/kg, P = .009. Univariate and multivariate regression confirmed a significant association between VO₂max and presence of pCR [AOR 1.26 (1.05-1.52), P = .015]. Duration of remission was longer among group with higher VO₂max results [15 (9-24) vs 9 (0-12) months, P = .043]. The positive relationship was observed between diabetes duration and VO₂max (rs = 0.484, P = .005). Multivariate linear regression confirms a significant association between remission duration and VO₂max (ml/min/kg) (ß = 0.595, P = .002). Conclusions The higher VO₂max, the better chance of partial clinical remission at 2 years of DM1 and longer duration of remission.

Measurement of Sedentary Behavior-The Outcomes of the Angle for Posture Estimation (APE) Method.

Hip-worn accelerometers are commonly used to assess habitual physical activity, but their accuracy in precisely measuring sedentary behavior (SB) is generally considered low. The angle for postural estimation (APE) method has shown promising accuracy in SB measurement. This method relies on the constant nature of Earth's gravity and the assumption that walking posture is typically upright. This study investigated how cardiorespiratory fitness (CRF) and body mass index (BMI) are related to APE output. A total of 3475 participants with adequate accelerometer wear time were categorized into three groups according to CRF or BMI. Participants in low CRF and high BMI groups spent more time in reclining and lying postures (APE ≥ 30°) and less time in sitting and standing postures (APE < 30°) than the other groups. Furthermore, the strongest partial Spearman correlation with CRF (r = 0.284) and BMI (r = -0.320) was observed for APE values typical for standing. The findings underscore the utility of the APE method in studying associations between SB and health outcomes. Importantly, this study emphasizes the necessity of reserving the term "sedentary behavior" for studies wherein the classification of SB is based on both intensity and posture.

Longitudinal associations of meeting the WHO physical activity guidelines and physical fitness, from preschool to childhood.

There is a well-established relationship between physical activity (PA) and physical fitness in children, being the latter an important marker for present and future health; however, there is still insufficient knowledge for the transition from the preschool age to early childhood. Therefore, this study in Swedish children aimed to investigate the estimated effect of meeting the aerobic component of the PA guidelines at 4 and/or 9 years of age on physical fitness measured at 9 years of age. PA was assessed using a wrist-worn ActiGraph accelerometer and identical data processing in 217 healthy children in Sweden (114 boys and 103 girls). Physical fitness test included cardiorespiratory (20 m shuttle run test), motor (4 × 10 m shuttle run), and muscular fitness (hand grip strength and long jump). A linear mixed model was run, investigating the interaction between meeting the PA guidelines and time (either 4 or 9 years of age) and each fitness component (at 4 and 9). Interactions by sex were also checked. Meeting the PA guidelines consistently (at 4 and 9 years) was significantly associated to better performance in physical fitness parameters for motor fitness (-0.76 s, p < 0.001) and lower body muscular fitness (+4.6 cm; p < 0.001) at 9 years. There was an interaction between meeting the PA guidelines and time point, for cardiorespiratory fitness (+4.58 laps; p < 0.001). This study shows that meeting the PA guidelines at 4 and 9 years of age is associated to higher physical fitness at 9 years of age.

Maximal cardiopulmonary exercise testing in glioblastoma patients undergoing chemotherapy: assessment of feasibility, safety, and physical fitness status.

PURPOSE: Maximal cardiopulmonary exercise testing (max. CPET) provides the most accurate measurement of cardiorespiratory fitness. However, glioblastoma (GBM) patients often undergo less intensive tests, e.g., 6-min walk test or self-rating scales. This study aims to demonstrate feasibility and safety of max. CPET in GBM patients, concurrently evaluating their physical fitness status. METHODS: Newly diagnosed GBM patients undergoing adjuvant chemotherapy were offered participation in an exercise program. At baseline, max. CPET assessed cardiorespiratory fitness including peak oxygen consumption (VO2peak), peak workload, and physical work capacity (PWC) at 75% of age-adjusted maximal heart rate (HR). Criteria for peak workload were predefined based on threshold values in HR, respiratory quotient, respiratory equivalent, lactate, and rate of perceived effort. Data were compared to normative values. Adverse events were categorized according to standardized international criteria. Further, self-reported exercise data pre- and post-diagnosis were gathered. RESULTS: All 36 patients (median-aged 60; 21 men) met the predefined criteria for peak workload. Mean absolute VO2peak was 1750 ± 529 ml/min, peak workload averaged 130 ± 43 W, and mean PWC was 0.99 ± 0.38 W/kg BW, all clinically meaningful lower than age- and sex-predicted normative values (87%, 79%, 90%, resp.). Only once (3%) a minor, transient side effect occurred (post-test dizziness, no intervention needed). Self-reported exercise decreased from 15.8 MET-h/week pre-diagnosis to 7.2 MET-h/week post-diagnosis. CONCLUSION: Max. CPET in this well-defined population proved feasible and safe. GBM patients exhibit reduced cardiorespiratory fitness, indicating the need for tailored exercise to enhance health and quality of life. CPET could be essential in establishing precise exercise guidelines.

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

INTRODUCTION:  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. OBJECTIVE:  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. MATERIALS AND METHODS: 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, the CRF. 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. RESULTS:  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. CONCLUSION: 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.

Cardiometabolic and immune response to exercise training in patients with metabolic syndrome: retrospective analysis of two randomized clinical trials.

Background: Metabolic syndrome (MetS) is defined by the presence of central obesity plus ≥two metabolic/cardiovascular risk factors (RF), with inflammation being a major disease-driving mechanism. Structured endurance exercise training (ET) may positively affect these traits, as well as cardiorespiratory fitness (V̇O2peak). Aims: We explore individual ET-mediated improvements of MetS-associated RF in relation to improvements in V̇O2peak and inflammatory profile. Methods: MetS patients from two randomized controlled trials, ExMET (n = 24) and OptimEx (n = 34), had performed 4- or 3-months supervised ET programs according to the respective trial protocol. V̇O2peak, MetS-defining RFs (both RCTs), broad blood leukocyte profile, cytokines and plasma proteins (ExMET only) were assessed at baseline and follow-up. Intra-individual changes in RFs were analysed for both trials separately using non-parametric approaches. Associations between changes in each RF over the exercise period (n-fold of baseline values) were correlated using a non-parametrical approach (Spearman). RF clustering was explored by uniform manifold approximation and projection (UMAP) and changes in RF depending on other RF or exercise parameters were explored by recursive partitioning. Results: Four months of ET reduced circulating leukocyte counts (63.5% of baseline, P = 8.0e-6), especially effector subtypes. ET response of MetS-associated RFs differed depending on patients' individual RF constellation, but was not associated with individual change in V̇O2peak. Blood pressure lowering depended on cumulative exercise duration (ExMET: ≥102 min per week; OptimEx-MetS: ≥38 min per session) and baseline triglyceride levels (ExMET: <150 mg/dl; OptimEx-MetS: <174.8 mg/dl). Neuropilin-1 plasma levels were inversely associated with fasting plasma triglycerides (R: -0.4, P = 0.004) and changes of both parameters during the ET phase were inversely correlated (R: -0.7, P = 0.0001). Conclusions: ET significantly lowered effector leukocyte blood counts. The improvement of MetS-associated cardiovascular RFs depended on individual basal RF profile and exercise duration but was not associated with exercise-mediated increase in V̇O2peak. Neuropilin-1 may be linked to exercise-mediated triglyceride lowering.

Measurement protocols and determinants of peak oxygen consumption in adults with Down syndrome: a systematic review.

This systematic review aimed to provide an overview of test protocols used to measure peak oxygen uptake (VO2peak) in adults with Down syndrome (DS) and to determine how generalisable the outcomes are for the entire population of adults with DS by describing the sample characteristics of these studies and their impact on VO2peak. A literature search (PROSPERO CRD42022309560) was performed (18 July 2023) using the following databases: PubMed, CINAHL, APA PsycINFO, Web of Science, Embase and SPORTDiscus. For articles to be included, they had to be peer-reviewed pubications, reporting VO2peak or VO2max for individuals with DS separately, with a sample of n ≥ 5 and a mean age ≥18 years. Systematic reviews and meta-analyses were excluded but their reference lists were searched for additional papers to include. Studies were evaluated for risk of bias following the guidelines of Kmet et al. The results were summarised with frequency statistics. Forty-three studies were included in this systematic review. Sample sizes of included adults with DS ranged from n = 4-226, with a total of n = 1498 adults with DS being included. Most studies (29/43) used the same standardised maximal exercise treadmill protocol to measure VO2peak in adults with DS, and 33 out of 43 studies used at least one objective criterion to determine a valid maximal effort. Participants were predominantly male, under 40 years old, and overweight or obese. Additionally, the diversity of study samples was lacking or not reported. The most widely used, standardised, maximal exercise test treadmill protocol is recommended for future use in research and practice, including objective criteria to determine valid maximal effort. The current study samples are not representative of the population of adults with DS in terms of sex, age and diverse backgrounds and therefore likely overestimate VO2peak of this population.

Fitness and fatness in children and adolescents: investigating their role in the association between physical activity and cardiometabolic health.

To verify the role of the combination of fitness and fatness in the relationship between physical activity (PA) and cardiometabolic risk in children and adolescents. This is a cross-sectional study performed with 2786 children and adolescents (6 to 17 years). Fitness was determined by the cardiorespiratory fitness (CRF) six-minute walking and running test. Waist circumference (WC) was considered a fatness indicator. A selfreported questionnaire was used to determine PA practice, whereas the clustered cardiometabolic risk score (cMetS) was calculated by summing z-scores of triglycerides, total cholesterol/HDL-C ratio, systolic blood pressure, glucose, and WC. Considering the combination of CRF (fitness) and WC (fatness), the following phenotypes were created: Fit/Unfat, Fit/Fat, Unfit/Unfat and Unfit/Fat. Moderation analyses were tested using linear regression models. Significant interactions were found between PA and Unfit/Fat category (ß = -0.001; p = 0.001) only for adolescents. The interaction observed in the Unfit/Fat phenotype indicated that adolescents who practise PA for 330 minutes per week presented lower cMetS compared to those who do not practise or practise for 60 minutes respectively. The combination of fitness and fatness moderates the relationship between PA and cardiometabolic risk, suggesting that adolescents, particularly those who are less fit and present high adiposity, should be encouraged to engage in regular PA to improve their metabolic health.

The effect of cardiorespiratory fitness and habitual physical activity on cardiovascular responses to 2-hours of uninterrupted sitting.

Prolonged uninterrupted sitting of >3-hours has been shown to acutely cause central and peripheral cardiovascular dysfunction. However, individuals rarely sit uninterrupted for >2-hours, and the cardiovascular response to this time is currently unknown. In addition, whilst increased cardiorespiratory fitness (CRF) and habitual physical activity (HPA) are independently associated with improvements in central and peripheral cardiovascular function, it remains unclear whether they influence the response to uninterrupted sitting. This study sought to 1) determine whether 2-hours of uninterrupted sitting acutely impairs carotid-femoral pulse wave velocity (cfPWV), femoral ankle PWV (faPWV), and central and peripheral blood pressure, and (2) to investigate the associations between CRF and HPA versus PWV changes during uninterrupted sitting. Following 2-hours of uninterrupted sitting, faPWV significantly increased (mean difference [MD] = 0.26 m·s-1, standard error [SE] = 0.10, p = 0.013) as did diastolic blood pressure (MD = 2.83 mmHg, SE = 1.08, p = 0.014), however cfPWV did not significantly change. Whilst our study shows 2-hours uninterrupted sitting significantly impairs faPWV, neither CRF (r = 0.105, p = 0.595) nor HPA (r = -0.228, p = 0.253) were associated with the increases.

Cardiorespiratory Fitness Benefits of Long-Term Maintenance-Phase Cardiac Rehabilitation in Males and Females: A Retrospective Cohort Study.

Purpose: This study investigated if associations exist between enrolment delay and VO2peak over five years of maintenance-phase cardiac rehabilitation (CR) in males and females. Method: Data were extracted from the records of participants who had enrolled for ≥ 1 year in CR and completed ≥ 2 cardiopulmonary exercise tests. Mixed model analyses examined VO2peak trajectories for up to five years of enrolment. Interactions between enrolment delay × enrolment duration, baseline age × enrolment duration, and baseline VO2peak × enrolment duration were explored for inclusion in the model. Results: The charts of 151 males (aged 63.9 ± 9.4 y) and 32 females (aged 65.3 ± 9.0 y) were included in the analyses. The enrolment delay following a cardiovascular event was 1.8 ± 3.0 years for males and 1.3 ± 1.7 years for females. No associations were found between enrolment delay × enrolment duration on VO2peak in males (ß[SEj, 0.07[0.05]; 95% CI -0.02, 0.16, p = 0.12) or in females (ß[SE], 0.07[0.13j; 95% CI -0.18, 0.33, p = 0.57), but predicted trajectories suggest clinically significantly improvements in VO2 peak (range, 1.3 to 1.6 mL/kg/min). Conclusions: Early enrolment in CR is recommended and encouraged, but the benefits of long-term CR are possible despite delays.

Objectif: étudier les associations éventuelles entre le retard d'inscription et la consommation maximale d'oxygène (VO2 max) pendant une phase d'entretien de cinq ans de la réadaptation cardiaque (RC) chez des hommes et des femmes. Méthodologie: données extraites des dossiers des participants inscrits en RC pendant au moins un an et qui ont effectué au moins deux épreuves d'effort cardiorespiratoire. Par des analyses en modèle mixte, les chercheurs ont examiné les trajectoires de VO2 max pendant une période d'inscription maximale de cinq ans. Ils ont exploré les interactions entre le retard d'inscription × la durée d'inscription, entre l'âge au départ × la durée d'inscription et entre la VO2 max au départ × la durée d'inscription pour les inclure dans le modèle. Résultats: les dossiers de 151 hommes (de 63,9 ± 9,4 ans) et de 32 femmes (de 65,3 ± 9,0 ans) ont été inclus dans les analyses. Après un événement cardiovasculaire, les hommes présentaient un retard d'inscription de 1,8 ± 3,0 ans et les femmes, de 1,3 ± 1,7 an. Les chercheurs n'ont constaté aucune association entre le retard d'inscription × la durée d'inscription et la VO2 max chez les hommes (ß[ET], 0,7[0,05]; IC à 95 % −0,02, 0,16, p = 0,12) ni chez les femmes (ß[ET], 0,07[0,13]; IC à 95 % −0,18, 0,33, p = 0,57), mais les trajectoires anticipées laissent supposer des améliorations cliniquement significatives de la VO2 max (plage de 1,3 à 1,6 mL/kg/min). Conclusions: il est recommandé et encouragé de s'inscrire rapidement en RC, mais la RC à long terme peut comporter des avantages malgré les retards d'inscription.

Qualitative systems mapping in promoting physical activity and cardiorespiratory fitness: Perspectives and recommendations.

The purpose of this report is to provide a perspective on the use of qualitative systems mapping, provide examples of physical activity (PA) systems maps, discuss the role of PA systems mapping in the context of iterative learning to derive breakthrough interventions, and provide actionable recommendations for future work. Systems mapping methods and applications for PA are emerging in the scientific literature in the study of complex health issues and can be used as a prelude to mathematical/computational modeling where important factors and relationships can be elucidated, data needs can be prioritized and guided, interventions can be tested and (co)designed, and metrics and evaluations can be developed. Examples are discussed that describe systems mapping based on Group Model Building or literature reviews. Systems maps are highly informative, illustrate multiple components to address PA and physical inactivity issues, and make compelling arguments against single intervention action. No studies were identified in the literature scan that considered cardiorespiratory fitness the focal point of a systems maps. Recommendations for future research and education are presented and it is concluded that systems mapping represents a valuable yet underutilized tool for visualizing the complexity of PA promotion.

Curvilinear association between waist-to-height ratio and cardiorespiratory fitness: a cross-sectional study based on nationwide data from Chinese children and adolescents.

BACKGROUND: Waist-to-height ratio (WHtR) is considered an important summary indicator for assessing the health of children and adolescents. However, there are fewer studies addressing the association between WHtR and cardiorespiratory fitness (CRF). Deriving an optimal WHtR would play an important role in promoting CRF in children and adolescents. Our aim was to analyze the association between WHtR and CRF and determine the optimal value of WHtR. METHODS: In this study, 37,081 (19,125 boys, 51.6%) children and adolescents aged 7-18 years in five regions of China were tested for WHtR and 20-m shuttle run test (20 m SRT). One-way ANOVA was used to compare maximum oxygen uptake (VO2max) among children and adolescents with different WHtRs and effect sizes were used to analyze differences between groups. Curvilinear regression was used to analyse the curvilinear relationship that exists between WHtR and VO2max. RESULTS: In Chinese children and adolescents, the WHtR of boys was higher than that of girls by 0.01, and the difference was statistically significant (P < 0.001). Overall, in the age groups of 7-9, 10-12, 13-15, and 16-18 years old, the differences in VO2max comparisons between different WHtR groups were statistically significant (P < 0.001). In Chinese children and adolescents in the age groups of 7-9, 10-12, 13-15, and 16-18 years old, VO2max levels were highest when the WHtR was 0.34, 0.32, 0.39, and 0.41, respectively. CONCLUSIONS: There is a curvilinear association between WHtR and CRF in Chinese children and adolescents. Both lower and higher WHtR led to a decrease in VO2max in children and adolescents.

Combined aerobic and strength exercise training on biological ageing in Singaporean breast cancer patients: protocol for the Breast Cancer Exercise Intervention (BREXINT) Pilot Study.

Breast cancer (BC) is the most prominent cancer amongst women, but fortunately, early diagnosis and advances in multimodality treatments have improved patient survivability. Cancer survivors, however, experience increased biological ageing which may accelerate other co-morbidities. Exercise intervention is a promising clinical adjuvant approach to improve BC patients' physiological function, recovery from treatment, and quality of life. However, the effects of combined aerobic and strength exercise training on biological ageing in BC patients have not been studied. The Breast Cancer Exercise Intervention (BREXINT) Pilot Study will evaluate the effects of a 24-week combined aerobic and strength exercise intervention against usual care in 50 BC patients' post-treatment randomised to either group. The primary outcomes include changes in cardiorespiratory fitness, muscle strength, cancer-related symptoms, and rate of biological ageing following exercise intervention period. The secondary outcomes include habitual physical activity measured with tri-axial accelerometery and supporting questionnaires, including physical activity, food diary, and quality of life questionnaires. This study will identify the effects of combined aerobic exercise strength training on biological ageing in BC patients from Singapore. Results from this study could further support the implementation of regular exercise programmes as routine care for cancer patients.

Genetic Background of Acute Heart Rate Response to Exercise.

The acute heart rate response (AHRR) to physical activity, which refers to the change in heart rate during and after exercise, has been associated with cardiovascular and all-cause mortality. Previous studies have shown that AHRR is significantly determined by genetics in addition to environmental and lifestyle factors. The aim of this study was to investigate the genetic background of AHRR by analysing ten single nucleotide polymorphisms (SNPs) associated with leisure-time physical activity (LTPA) in 620 samples from the Hungarian population. The AHRR can be characterised as the difference between post-exercise and resting heart rate, i.e., the delta heart rate (ΔHR) defined by the YMCA 3 min step test, with a lower value indicating better cardiovascular fitness. The association of SNPs with ΔHR was analysed both separately and in combination using an optimised polygenic score (oPGS). The results showed that five SNPs (rs10252228, rs459465, rs6022999, rs8097348, and rs12405556) had at least nominally significant (p < 0.05) individual associations with ΔHR. After optimizing the PGS, a cumulative effect was observed for eight SNPs (rs6022999, rs12405556, rs459465, rs10252228, rs8097348, rs10887741, rs12612420, and rs7023003) that had a strong and statistically significant association with ΔHR (B = -2.51, 95% CI: -3.46--1.76; p = 2.99 × 10-9). Of the four main domains of physical activity, the oPGS showed a significant positive association only with LTPA (B = 84.60; 95%CI: 25.23-143.98; p = 0.005). In conclusion, our results suggest that the SNPs we investigated influence individual leisure-time physical activity, mediated by their effects on the acute heart rate response.

Development, validation, and transportability of several machine-learned, non-exercise-based VO2max prediction models for older adults.

PURPOSE: There exist few maximal oxygen uptake (VO2max) non-exercise-based prediction equations, fewer using machine learning (ML), and none specifically for older adults. Since direct measurement of VO2max is infeasible in large epidemiologic cohort studies, we sought to develop, validate, compare, and assess the transportability of several ML VO2max prediction algorithms. METHODS: The Baltimore Longitudinal Study of Aging (BLSA) participants with valid VO2max tests were included (n = 1080). Least absolute shrinkage and selection operator, linear- and tree-boosted extreme gradient boosting, random forest, and support vector machine (SVM) algorithms were trained to predict VO2max values. We developed these algorithms for: (a) for the overall BLSA, (b) by sex, (c) using all BLSA variables, and (d) for variables common in aging cohorts. Finally, we quantified the associations between measured and predicted VO2max and mortality. RESULTS: The age was 69.0 ± 10.4 years (mean ± SD) and the measured VO2max was 21.6 ± 5.9 mL/kg/min. Least absolute shrinkage and selection operator, linear- and tree-boosted extreme gradient boosting, random forest, and support vector machine yielded root mean squared errors of 3.4 mL/kg/min, 3.6 mL/kg/min, 3.4 mL/kg/min, 3.6 mL/kg/min, and 3.5 mL/kg/min, respectively. Incremental quartiles of measured VO2max showed an inverse gradient in mortality risk. Predicted VO2max variables yielded similar effect estimates but were not robust to adjustment. CONCLUSION: Measured VO2max is a strong predictor of mortality. Using ML can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to adjustment. Future studies should seek to reproduce these results so that VO2max, an important vital sign, can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

The Effects of Exergame Telerehabilitation in Persons with Subjective Cognitive Decline.

BACKGROUND AND OBJECTIVES: The primary aim of this Stage IB randomized controlled trial (RCT) was to test the preliminary effects of a dual-task exergaming telerehabilitation intervention on cognition and aerobic fitness, compared to aerobic exercise (AEx) only and attention control (stretching) in older adults with SCD. RESEARCH DESIGN AND METHODS: This RCT randomized 39 participants on a 2:1:1 allocation ratio to supervised exergame (n=20), AEx (n=11), and stretching (n=8) for 12 weeks. The dual-task exergaming was concurrent moderate-intensity cycling and BrainFitRx® cognitive telerehabilitation. Cognition was assessed by NIH Toolbox Cognitive Battery and aerobic fitness by 6-minute walk test (6MWT) and shuttle walk test. RESULTS: The participants were 74.6 (7.4) years old and 69% were female. The effect of time was significant, F(1,23.9) = 13.16, p =.001, for the Fluid Composite score, and significant within-group changes were seen for the exergame group, t(14.08) = 2.53, p = .024, d = 0.33. Between-group changes did not reach significant levels for any cognitive test. Between-group changes for the 6MWT were not significant. DISCUSSION AND IMPLICATIONS: The exergame participants further improved their fluid cognition, while the AEx and stretching groups did not, indicating a potential synergistic effect from AEx and cognitive training. The aerobic fitness changes were similar between the exergame and AEx only groups, indicating that the feasibility of adding cognitive training to AEx concurrently without sacrificing gains in aerobic fitness from AEx. This study shows the flexibility of exergame delivery and its potentially therapeutic effects in persons at risk for Alzheimer's dementia.

Cardiorespiratory fitness mediates cortisol and lactate responses to winter and summer marches.

Background: The influence of homeostatically regulated physiological processes, including cardiorespiratory fitness (VO2max), on the response to physical stressors such as acclimatisation and marching, remains understudied. We aimed to investigate the effects of summer and winter acclimatisation and marching on cortisol levels and blood lactate, to gain insight into the role of these physiological processes in the stress response. Methods: Two groups of young Europeans, classified as poor (PCF; n=9) and good physical condition (GCF; n=21), based on a VO2MAX threshold of 40 mL O2/ kg/min, underwent 2-h March (6-7 km/h) in winter (5˚C) and summer (32˚C). Commercial tests, UniCel DxI Access Cortisol assay and EKF Biosen Clinic/GP assay were used for cortisol and lactate blood measurements (morning samples and those taken immediately after marches), respectively.

Exercise to Mitigate Cerebrovascular Aging: A Geroscience Perspective.

Aging is characterized by a progressive loss of cellular functions that increase the risk of developing chronic diseases, vascular dysfunction, and neurodegenerative conditions. The field of geroscience has identified cellular and molecular hallmarks of aging that may serve as targets for future interventions to reduce the risk of age-related disease and disability. These hallmarks include genomic instability, telomere attrition, epigenetic alterations, loss of proteostasis, deregulated nutrient-sensing, mitochondrial dysfunction, cellular senescence, stem cell exhaustion, and altered intercellular communication. Several studies show that exercise may favorably impact these processes and thereby have anti-aging properties. The primary mechanisms through which exercise confers protective benefits in the brain are still incompletely understood. To better understand these effects and leverage them to help promote brain health, we present current findings supporting the notion that adaptive responses to exercise play a pivotal role in mitigating the hallmarks of aging and their effects on the aging cerebrovasculature, and ultimately contribute to the maintenance of brain function across the health span.

Beyond change scores: Employing an improved statistical approach to analyze the impact of entry fitness on physical performance during British Army basic training in men and women.

The aim was to use a robust statistical approach to examine whether physical fitness at entry influences performance changes between men and women undertaking British Army basic training (BT). Performance of 2 km run, seated medicine ball throw (MBT) and isometric mid-thigh pull (MTP) were assessed at entry and completion of Standard Entry (SE), Junior Entry-Short (JE-Short), and Junior Entry-Long (JE-Long) training for 2350 (272 women) recruits. Performance change was analyzed with entry performance as a covariate (ANCOVA), with an additional interaction term allowing different slopes for courses and genders (p < 0.05). Overall, BT courses saw average improvements in 2 km run performance (SE: -6.8% [-0.62 min], JE-Short: -4.6% [-0.43 min], JE-Long: -7.7% [-0.70 min]; all p < 0.001) and MBT (1.0-8.8% [0.04-0.34 m]; all p < 0.05) and MTP (4.5-26.9% [6.5-28.8 kg]; all p < 0.001). Regression models indicate an expected form of "regression to the mean" whereby test performance change was negatively associated with entry fitness in each course (those with low baseline fitness exhibit larger training improvements; all interaction effects: p < 0.001, η p 2 $$ {\eta}_{\mathrm{p}}^2 $$ > 0.006), particularly for women. However, when matched for entry fitness, men displayed considerable improvements in all tests, relative to women. Training courses were effective in developing recruit physical fitness, whereby the level of improvement is, in large part, dependent on entry fitness. Factors including age, physical maturity, course length, and physical training, could also contribute to the variability in training response between genders and should be considered when analyzing and/or developing physical fitness in these cohorts for future success of military job-task performance.

Home- vs gym-based exercise delivery modes of two multicomponent intensity training regimes on cardiorespiratory fitness and arterial stiffness in adults with intellectual and developmental disability during the COVID-19 pandemic - a randomized controlled trial.

Background: We compared the effects of home- vs gym-based delivery modes of two 8-week supervised multicomponent intensity training regimes on cardiorespiratory fitness and arterial stiffness in 17 adults with intellectual and developmental disability during the COVID-19 pandemic. Methods: Participants were assigned to sprint interval training or continuous aerobic training, both incorporating resistance training. The intervention started with 8-weeks of online training (M1-M2), 1-month of detraining, plus 8-weeks of gym-based training (M3-M4). Results: Peak oxygen uptake decreased from M1-M2 and increased from M2-M4. Central arterial stiffness decreased between M1-M2, and M1-M4, along with peripheral arterial stiffness. Central systolic blood pressure decreased from M1-M2 only with sprint interval training. Conclusion: Home-based training minimized the negative impact of the lockdown on central arterial stiffness and central blood pressure, but it did not match the benefits on cardiorespiratory fitness and peripheral arterial stiffness of a gym-based intervention, irrespective of the multicomponent intensity training regime. Registered in ClinicalTrials.gov NCT05701943.