The concurrent validity and test-retest reliability of a submaximal exercise test in adolescents with autism.

PURPOSE: There is a need for valid and reliable clinical assessment tools to assess cardiorespiratory fitness (CRF) levels in adolescents with autism. Therefore, this study aimed to examine the concurrent validity and test-retest reliability of the Astrand-Rhyming Test (ART) in this population. MATERIALS AND METHODS: 45 adolescents with autism aged 12-18 years (n = 32 males, 14.47 ± 1.79 years) performed the ART twice (test-retest reliability) and completed a maximal cardiopulmonary exercise test (CPET) (concurrent validity). Reliability parameters included Pearson correlations, intraclass correlation coefficients (ICCs), standard error of measurements (SEM), minimal detectable changes (MDC), coefficients of variation, paired sample t-tests, linear regressions and Bland-Altman plots. The concurrent validity was evaluated with Pearson correlations, ICCs, paired sample t-tests, linear regressions and Bland-Altman plots. RESULTS: Strong test-retest reliability (r = 0.84-0.85, ICC = 0.84-0.85) was found for the ART, but the wide limits of agreement intervals suggest the presence of substantial variability. The large SEM (4.73-5.08 mL/kg/min) and MDC (13.20-14.07 mL/kg/min) values suggest lower absolute reliability. Moderate to strong levels of association (r = 0.74-0.75) and agreement (ICC = 0.59-0.66) were found between estimated (ART1) and measured (CPET) VO2 max levels, but significant systematic differences (5.71-8.82 mL/kg/min) were observed. CONCLUSION: The ART is an accessible and promising method to monitor submaximal CRF levels over time but is less appropriate to estimate maximal CRF levels in this population.

Adolescents with autism are at increased risk of exhibiting low cardiorespiratory fitness (CRF) levels and as a result, placing them at risk for poor physical and mental health outcomes.In clinical practice, the CRF levels of this population should be screened and monitored routinely to identify those at risk and most likely to benefit from a targeted intervention.A submaximal exercise test appears to be feasible in adolescents with autism.The Astrand-Rhyming Test shows good reliability to monitor submaximal CRF levels over time, but is less appropriate to estimate maximal CRF levels in adolescents with autism.The use of the age correction factor of the Astrand-Rhyming Test nomogram is not required to adequately estimate CRF levels in adolescents with autism.

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.

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.

Health Benefits of Different Sports: a Systematic Review and Meta-Analysis of Longitudinal and Intervention Studies Including 2.6 Million Adult Participants.

BACKGROUND: Several reviews have examined the health benefits of participation in specific sports, such as baseball, cricket, cross-country skiing, cycling, downhill skiing, football, golf, judo, rugby, running and swimming. However, new primary studies on the topic have recently been published, and the respective meta-analytic evidence needs to be updated. OBJECTIVES: To systematically review, summarise and appraise evidence on physical health benefits of participation in different recreational sports. METHODS: Searches for journal articles were conducted in PubMed/MEDLINE, Scopus, SpoLit, SPORTDiscus, Sports Medicine & Education Index and Web of Science. We included longitudinal and intervention studies investigating physical health outcomes associated with participation in a given sport among generally healthy adults without disability. RESULTS: A total of 136 papers from 76 studies conducted among 2.6 million participants were included in the review. Our meta-analyses of available evidence found that: (1) cycling reduces the risk of coronary heart disease by 16% (pooled hazard ratio [HR] = 0.84; 95% confidence interval [CI]: 0.80, 0.89), all-cause mortality by 21% (HR = 0.79; 95% CI: 0.73, 0.84), cancer mortality by 10% (HR = 0.90; 95% CI: 0.85, 0.96) and cardiovascular mortality by 20% (HR = 0.80; 95% CI: 0.74, 0.86); (2) football has favourable effects on body composition, blood lipids, fasting blood glucose, blood pressure, cardiovascular function at rest, cardiorespiratory fitness and bone strength (p < 0.050); (3) handball has favourable effects on body composition and cardiorespiratory fitness (p < 0.050); (4) running reduces the risk of all-cause mortality by 23% (HR = 0.77; 95% CI: 0.70, 0.85), cancer mortality by 20% (HR = 0.80; 95% CI: 0.72, 0.89) and cardiovascular mortality by 27% (HR = 0.73; 95% CI: 0.57, 0.94) and improves body composition, cardiovascular function at rest and cardiorespiratory fitness (p < 0.010); and (5) swimming reduces the risk of all-cause mortality by 24% (HR = 0.76; 95% CI: 0.63, 0.92) and improves body composition and blood lipids (p < 0.010). CONCLUSIONS: A range of physical health benefits are associated with participation in recreational cycling, football, handball, running and swimming. More studies are needed to enable meta-analyses of health benefits of participation in other sports. PROSPERO registration number CRD42021234839.

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.

Physiological Responses and Performance during an Integrated High-Intensity Interval Aerobic and Power Training Protocol.

This study compared the acute physiological responses and performance changes during an integrated high-intensity interval aerobic and power protocol. Sixteen moderately trained athletes (age: 20.1 ± 2.2 years, body height: 180.0 ± 6.5 cm, body mass: 75.7 ± 6.4 kg, VO2max: 55.8 ± 4.3 mL/kg/min) performed a 2 × 6 min interval training protocol with 2 min passive recovery between sets on two different occasions in random and counterbalanced order. Each 6 min set included repeated periods of 15 s exercise interspersed with 15 s passive rest. On one occasion (RUN), all exercise periods included running at 100% of maximal aerobic speed, while on the other occasion an integrated protocol was used (INT) in which each of the two 6 min sets included 4 × 1.5 min periods of running exercise at 100% of maximal aerobic speed in combination with jumping (i.e., 2 × 15 running with 15 s rest and 1 × 15 s drop jumping with 15 s rest). Time spent above 85% HRmax was two-fold higher in INT compared to RUN (8.5 ± 3.6 vs. 4.3 ± 3.9 min, respectively, p = 0.0014). Interestingly, heart rate increased above 95% HRmax only in INT and almost no time was spent above 95% HRmax in RUN (1.4 ± 1.9 vs. 0.1 ± 0.2 min, respectively, p = 0.008). Blood lactate concentration at the end of the second set of INT was higher than RUN (7.3 ± 3.2 vs. 4.6 ± 2.7 mmol/L, p = 0.002). Countermovement jump was higher in INT after the end of second set by 6.4% (p = 0.04), 6.7% (p = 0.04), 7.8% (p < 0.01) and 7.3% (p < 0.001), at 2, 6 and 8 min after set 2. In conclusion, the comparison between INT and RUN shows that INT not only elicits higher physiological and metabolic responses, but also acutely enhances neuromuscular performance for at least 8 min after the end of exercise. The integrated running/jumping high-intensity interval exercise approach could be a very useful and time efficient method for strength and conditioning coaches, especially in team sports, in which the time available for the improvement of physical parameters is limited.

The Impact of Personalized versus Standardized Cardiorespiratory and Muscular Training on Health-Related Outcomes and Rate of Responders.

Recent research has shown more favorable training adaptations for inactive adults when cardiorespiratory fitness (CRF) exercise is prescribed with the use of ventilatory thresholds compared to percentages of heart rate reserve (HRR). However, there is limited research on changes in health-related outcomes with the use of these CRF methods in combination with muscular fitness exercises. The objective of this study was to compare the effectiveness of two training programs for improving CRF, muscular fitness, and cardiometabolic risk factors. Inactive men and women (n=109, aged 49.3±15.5 years) were randomized to a non-exercise control group or one of two exercise training groups. The exercise training groups consisted of 13 weeks of structured exercise with progression using either CRF exercise prescribed with the use of ventilatory thresholds and functional training for muscular fitness (THRESH group) or HRR and traditional muscular fitness training (STND group). After the 13-week protocol, there were significant differences in body weight, body composition, systolic blood pressure, high-density lipoprotein cholesterol (HDL-c), VO2max, 5-repetition maximum (RM) bench press, and 5-RM leg press for both treatment groups compared to the control group after controlling for baseline values. However, the THRESH group had significantly more desirable outcomes for VO2max, 5-RM bench press, 5-RM leg press, body composition, and HDL-c when compared to both the STND and control group. Additionally, the proportion of individuals estimated as likely to respond above 3.5 mL·kg-1·min-1 in VO2max (i.e., the minimal clinically important difference) was 76.4%, 20.8%, and 0.13% for the THRESH, STND, and control groups, respectively. While both exercise programs elicited favorable health-related adaptations after 13 weeks, these results suggest that a personalized program with exercise prescribed based on ventilatory threshold and with the use of functional muscular fitness training may yield greater training adaptations.

Assessing cardiorespiratory fitness in clinical and community settings: Lessons and advancements in the 100th year anniversary of VO2max.

Cardiorespiratory fitness (CRF) is a well-established biomarker that has applications to all adults across the health and disease spectrum. Despite overwhelming evidence supporting the prognostic utility of CRF, it remains vastly underutilized. CRF is optimally measured via cardiopulmonary exercise testing which may not be feasible to implement on a large scale. Therefore, it is prudent to develop ways to accurately estimate CRF that can be applied in clinical and community settings. As such, several prediction equations incorporating non-exercise information that is readily available from routine clinical encounters have been developed that provide an adequate reflection of CRF that could be implemented to raise awareness of the importance of CRF. Further, technological advances in smartphone apps and consumer-grade wearables have demonstrated promise to provide reasonable estimates of CRF that are widely available, which could enhance the utilization of CRF in both clinical and community settings.

Roselle (Hibiscus sabdariffa L.) calyces tea improves physical fitness of healthy adults.

Roselle calyces (Hibiscus sabdariffa L.) is a plant that contains anthocyanin and flavonoids, which function as exogenous antioxidants for the human body to counteract excess oxidative stress. Roselle has anti-hypertensive, anti-cancer and anti-diabetic effects. The present study evaluated roselle to see whether it affects physical fitness. The components of physical fitness include strength, balance, right and left hand grip, vertical jump and VO2max (maximum oxygen consumption). A total of 30 subjects received 200 ml rosella tea for 30 days every morning and evening. Every week, subjects were assessed for physical fitness. Data analysis used paired t and Wilcoxon test according to the normality test results. The results showed significant improvements in strength (from 24.9 to 27.3 kg; P=0.025), balance (from 23.3 to 42.2 sec; P=0.004), right (from 31.8 to 35.1 kg; P<0.0001) and left hand grip (from 29.8 to 31.6 kg; P=0.020), vertical jump (from 38.6 to 41.1 m/sec; P=0.008) and VO2max (from 31.1 to 34.3 ml/kg/min; P=0.014). This demonstrated that roselle significantly improved six parameters of physical fitness and may be used as a supplement to improve physical fitness without severe side effects.

Effect of exercise on functional capacity and body weight for people with hypertension, type 2 diabetes, or cardiovascular disease: a systematic review with meta-analysis and trial sequential analysis.

BACKGROUND: Hypertension, type 2 diabetes, and cardiovascular disease affect the activities of daily living at varying degree. While the effects of aerobic exercise on functional capacity are well-documented, the extent of change for different types of exercise in these chronic conditions remains unexplored. Additionally, there is conflicting evidence regarding the role of exercise in reducing body weight. METHODS: We conducted systematic review with meta-analysis and trial sequential analysis and searched various databases from inception to July 2020. We included randomised clinical trials adding any form of trialist defined exercise to usual care versus usual care in people with either hypertension, type 2 diabetes, and/or cardiovascular disease irrespective of setting, publication status, year, and language. The outcomes assessed were i) functional capacity assessed through different scales separately i.e., Maximal Oxygen Uptake (VO2max), 6-min walk test (6MWT), 10-m walk test (10MWT), and ii) body weight. RESULTS: We included 950 studies out of which 444 trials randomising 20,098 participants reported on various functional outcomes (355 trials) and body weight (169 trials). The median follow-up was 3 months (Interquartile ranges (IQR): 2.25 to 6). Exercise added to the usual care, improved VO2max (Mean Difference (MD):2.72 ml/kg/min; 95% Confidence Interval (CI) 2.38 to 3.06; p < 0.01; I2 = 96%), 6MWT (MD: 42.5 m; 95%CI 34.95 to 50.06; p < 0.01; I2 = 96%), and 10MWT (MD: 0.06 m/s; 95%CI 0.03 to 0.10; p < 0.01; I2 = 93%). Dynamic aerobic and resistance exercise showed a consistent improvement across various functional outcomes, whereas body-mind therapies (MD: 3.23 ml/kg/min; 95%CI 1.97 to 4.49, p < 0.01) seemed especially beneficial for VO2max and inspiratory muscle training (MD: 59.32 m; 95%CI 33.84 to 84.80; p < 0.01) for 6MWT. Exercise yielded significant reduction in body weight for people with hypertension (MD: -1.45 kg; 95%CI -2.47 to -0.43; p < 0.01), and type 2 diabetes (MD: -1.53 kg; 95%CI -2.19 to -0.87; p < 0.01) but not for cardiovascular disease with most pronounced for combined exercise (MD: -1.73 kg; 95%CI -3.08 to -0.39; p < 0.05). The very low certainty of evidence warrants cautious interpretations of the results. CONCLUSION: Exercise seemed to improve functional capacity for people with hypertension, type 2 diabetes, and/or cardiovascular disease but the effectiveness seems to vary with different forms of exercise. The potentially superior improvement in VO2max and 6MWT by body-mind therapies and inspiratory muscle training calls for further exploration. Additionally, prescribing exercise for the sole purpose of losing weight may be a potential strategy for people with hypertension and type 2 diabetes. The extent of improvement in functional capacity and body weight reduction differed with different exercise regimens hence personalised exercise prescriptions tailored to individual needs may be of importance. PROSPERO REGISTRATION: PROSPERO registration number: CRD42019142313.

Evaluation of Blood Lactate among Different Player Roles: A Pilot Study on Competitive Young Male Soccer Players.

BACKGROUND: Soccer match requires anaerobic and aerobic energetic metabolism. The aim of this pilot study was to investigate the changes in blood lactate concentration in young male soccer players in different playing roles at different time points after the soccer match. METHODS: Following an initial screening of 134 young soccer athletes, 8 male athletes (average age of 15.5 ± 5 SD) were chosen for their characteristics similar to those of competitive athletes. Players were categorized as goalkeeper, central defender, central midfielder, and forward. Blood lactate concentrations were determined using a portable device at different times (10 min, 5 and 16 h) after the soccer match by a maximum effort test on a treadmill. The data were analyzed by one-way analysis of variance ANOVA, followed by Bonferroni's post-hoc test. RESULTS: The following results (mean ± SD) were obtained: VO2max (%) 60.33 ± 3.10; blood lactate (mM) end match (10 min) 2.17 ± 0.78, post-match-early (after 5 h) 2.2 ± 0.42, postmatch-late (16 h) 3.2 ± 0.84. ANOVA analysis indicated that the blood LA concentrations at end-match (10 min) and post-match-early (5 h) were statistically significative lower than those determined at post-match-late (16 h) (p < 0.05). CONCLUSION: These results suggest that aerobic mechanisms can also use LA as an energy source, contributing to the reduction of its blood concentration. This effect can be due to reduced maximal work during a soccer match and to the LA removal during exercise at reduced intensity. These data can provide indications for planning suitable training strategies for young male soccer players.

Reference values for estimated VO2max by two submaximal cycle tests: the Åstrand-test and the Ekblom-Bak test.

AIMS: Submaximal tests estimating VO2max have inherent biases; hence, using VO2max estimations from the same test is essential for reducing this bias. This study aimed to establish sex- and age-specific reference values for estimated VO2max using the Åstrand-test (Å-test) and the Ekblom-Bak test (EB-test). We also assessed the effects of age, exercise level, and BMI on VO2max estimations. METHODS: We included men and women (20-69 years) from the Swedish working population participating in Health Profile Assessments between 2010 and 2020. Excluding those on heart rate-affecting medicines and smokers, n = 263,374 for the Å-test and n = 95,043 for the EB-test were included. VO2max reference values were based on percentiles 10, 25, 40, 60, 75, and 90 for both sexes across 5-year age groups. RESULTS: Estimated absolute and relative VO2max were for men 3.11 L/min and 36.9 mL/min/kg using the Å-test, and 3.58 L/min and 42.4 mL/min/kg using the EB-test. For women, estimated absolute and relative VO2max were 2.48 L/min and 36.6 mL/min/kg using the Å-test, and 2.41 L/min and 35.5 mL/min/kg using the EB-test. Higher age (negative), higher exercise level (positive), and higher BMI (negative) were associated with estimated VO2max using both tests. However, explained variance by exercise on estimated VO2max was low, 10% for the Å-test and 8% for the EB-test, and moderate for BMI, 23% and 29%. CONCLUSION: We present reference values for estimated VO2max from two submaximal cycle tests. Age, exercise, and BMI influenced estimated VO2max. These references can be valuable in clinical evaluations using the same submaximal tests.

Exploring the Hidden Complexity: Entropy Analysis in Pulse Oximetry of Female Athletes.

This study examines the relationship between physiological complexity, as measured by Approximate Entropy (ApEn) and Sample Entropy (SampEn), and fitness levels in female athletes. Our focus is on their association with maximal oxygen consumption (VO2,max). Our findings reveal a complex relationship between entropy metrics and fitness levels, indicating that higher fitness typically, though not invariably, correlates with greater entropy in physiological time series data; however, this is not consistent for all individuals. For Heart Rate (HR), entropy measures suggest stable patterns across fitness categories, while pulse oximetry (SpO2) data shows greater variability. For instance, the medium fitness group displayed an ApEn(HR) = 0.57±0.13 with a coefficient of variation (CV) of 22.17 and ApEn(SpO2) = 0.96±0.49 with a CV of 46.08%, compared to the excellent fitness group with ApEn(HR) = 0.60±0.09 with a CV of 15.19% and ApEn(SpO2) =0.85±0.42 with a CV of 49.46%, suggesting broader physiological responses among more fit individuals. The larger standard deviations and CVs for SpO2 entropy may indicate the body's proficient oxygen utilization at higher levels of physical demand. Our findings advocate for combining entropy metrics with wearable sensor technology for improved biomedical analysis and personalized healthcare.

HRV-guided training vs traditional HIIT training in cardiac rehabilitation: a randomized controlled trial.

High-intensity interval training is the gold standard for cardiac rehabilitation although current revascularization therapy focuses on the recovery of autonomic nervous system balance through heart rate variability (HRV). The main objective was to analyze the effect of HRV-guided training versus high-intensity interval training on cardiorespiratory fitness, heart rate variability, quality of life, and training volume at high intensity, as well as exercise adherence, safety, and feasibility in ischemic patients. This is an 8-week cluster randomized controlled trial with an HRV-based training group (HRV-G) and a traditional HIIT group (HIIT-G). Maximal oxygen consumption, heart rate, and blood pressure were measured during the Bruce protocol treadmill test. HRV was measured with the HRV4Training application, and quality of life with the MacNew QLMI. The repeated measures ANCOVA was used with the age and the baseline scores as covariables. Forty-six patients (mean age 55 ± 11.03 years) were randomized and assigned either to HRV-G (n = 23) or HIIT-G (n = 23). Both groups improved maximal oxygen consumption and METS (P > .05). However, the resting systolic blood pressure was lower in HRV-G (4.3 ± 1.2 mmHg, P = .05). In HRV-G, the resting diastolic, maximal diastolic, and systolic blood pressure decreased (5.4 ± 5.96 mmHg, P = .007; 11.4 ± 12.46 mmHg, P = .005; and 5 ± 5.98 mmHg, P = .013, respectively) whereas the recovery heart rate increased significantly (-21.5 ± 23.16 beats/min, P = .003). The LnrMSSDcv ([LnrMSSDSD/LnrMSSDMEAN] × 100) was lower in HRV-G (1.23 ± 0.91 mmHg, P = .03) while the training volume at high intensity was higher in HIIT-G (31.4 ± 29.2 min, P = .024). HRV-guided training presents a better cardioprotective effect than HIIT-G at a lower high-intensity training volume.

Effects of a brief HIIT intervention on cognitive performance in older women.

Cardiorespiratory fitness (CRF) mitigates age-related decline in cognition and brain volume. Little is known, however, about the effects of high-intensity interval training (HIIT) on cognitive aging and the relationship between HIIT, cognition, hippocampal subfield volumes, and cerebral oxygen extraction fraction (OEF). Older sedentary women participated in an 8-week HIIT intervention. We conducted cognitive assessments, fitness assessments (VO2max), MRI scans: asymmetric spin echo oxygen extraction fraction (ASE-OEF), high-resolution multiple image co-registration and averaging (HR-MICRA) imaging, and transcranial Doppler ultrasonography before and after the intervention. VO2max increased from baseline (M = 19.36, SD = 2.84) to follow-up (M = 23.25, SD = 3.61), Z = - 2.93, p < .001, r = 0.63. Composite cognitive (Z = - 2.05, p = 0.041), language (Z = - 2.19, p = 0.028), and visuospatial memory (Z = - 2.22, p = 0.026), z-scores increased significantly. Hippocampal subfield volumes CA1 and CA3 dentate gyrus and subiculum decreased non-significantly (all p > 0.05); whereas a significant decrease in CA2 (Z = - 2.045, p = 0.041, r = 0.436) from baseline (M = 29.51; SD = 24.50) to follow-up (M = 24.50; SD = 13.38) was observed. Right hemisphere gray matter was correlated with language z-scores (p = 0.025; r = 0.679). The subiculum was correlated with attention (p = 0.047; r = 0.618) and verbal memory (p = 0.020; r = 0.700). The OEF and CBF were unchanged at follow-up (all p > .05). Although we observed cognitive improvements following 8 weeks of our HIIT intervention, they were not explained by hippocampal, OEF, or CBF changes.

Health and performance effects of 12 weeks of small-sided street football training compared to grass football training in habitually active young men.

PURPOSE: The purpose of the present study was to investigate the health and exercise performance effects of street football training on very small pitches surrounded by boards in young habitually active men in comparison to small-sided football training on grass. METHODS: Thirty-nine habitually active men (30.7 ± 6.7 years, 90.9 ± 16.6 kg, 183.8 ± 4.5 cm, 39.6 ± 6.0 mL/min/kg) were randomly assigned to a street football training group (ST) or grass football group (GR) playing small-sided games for 70 min, 1.5 and 1.7 times per week for 12 weeks, respectively, or an inactive control group (CO). Intensity during training was measured using heart rate (HR) and GPS units. Pre- and post-intervention, a test battery was completed. RESULTS: Mean HR (87.1 ± 5.0 vs. 84.0 ± 5.3%HRmax; P > 0.05) and percentage of training time above 90%HRmax (44 ± 28 vs. 34 ± 24%; P > 0.05) were not different between ST and GR. VO2max increased (P < 0.001) by 3.6[95% CI 1.8;5.4]mL/min/kg in GR with no significant change in ST or CO. HR during running at 8 km/h decreased (P < 0.001) by 14[10;17]bpm in ST and by 12[6;19]bpm in GR, with no change in CO. No changes were observed in blood pressure, resting HR, total body mass, lean body mass, whole-body bone mineral density, fasting blood glucose, HbA1c, plasma insulin, total cholesterol(C), LDL-C or HDL-C. Moreover, no changes were observed in Yo-Yo IE2 performance, 30-m sprint time, jump length or postural balance. CONCLUSION: Small-sided street football training for 12 weeks with 1-2 weekly sessions led to improvements in submaximal exercise capacity only, whereas recreational grass football training confirmed previous positive effects on submaximal exercise capacity as well as cardiorespiratory fitness.

Relationship between aerobic fitness and lower limb skin temperature during cycling exercise testing among well-trained athletes and nonathletes: a cross-sectional study.

Background: During prolonged physical exercise, the skin plays an important role in thermoregulation by dissipating heat to maintain core temperature. Moreover, thermal variation may be influenced by the physical fitness level of an individual. The aim of the present study was to determine the relationship between aerobic fitness and lower limb skin temperature during graded cycling exercise testing in well-trained athletes and nonathletes. Methods: Twelve trained athletes (mean ± SD maximal oxygen consumption [VO2max], 52.44 ± 4.5 ml/kg/min) and 12 nonathletes (VO2max, 36.95 ± 4.9 ml/kg/min) participated in this study. The regional skin temperature over the lower limbs was monitored continuously during incremental exercise testing using a thermal camera, and cardio-respiratory parameters were assessed and recorded using a metabolic analyzer (K5, COSMED, Rome, Italy). Results: The mean skin temperature of athletes at a high intensity of exercise was 27.23 ± 0.3 °C while that of nonathletes was 29.03 ± 0.44 °C, a difference that was statistically significant (p < 0.05). A negative correlation was observed between skin temperature and cardiovascular parameters (VO2max and heart rate) in athletes, while no such correlation was found among nonathletes. Conclusion: The present study demonstrated a negative correlation between oxygen consumption and lower limb skin temperature in athletes, while the correlation was poor in nonathletes. This suggests that physical fitness level may influence the pattern of alterations in lower limb skin temperature, which supports the hypothesis that athletes exhibit better heat dissipation mechanisms than nonathletes.

Comparison of VO2max Estimations for Maximal and Submaximal Exercise Tests in Apparently Healthy Adults.

Due to limited accessibility, direct measurement of VO2max is rarely performed in clinical settings or sports centers. As a result, regression equations have been developed and are currently used during exercise tests to provide an indirect estimation. The American College of Sports Medicine (ACSM) has recommended a regression equation for running to provide an indirect estimation of VO2. However, significant differences have been observed between these estimations and directly measured VO2max. Additionally, since submaximal assessments may be more convenient for both athletes and sedentary/diseased individuals, they were included in the analysis. This study aimed to evaluate the accuracy of VO2max estimations provided using the ACSM running equation when used during both maximal and submaximal exercise tests among adult runners. A total of 99 apparently healthy and active adults (age: 39.9 ± 12.2 years; VO2max: 47.4 ± 6.0 mL O2/kg∙min-1) participated in this study. Two types of submaximal estimations were performed to predict VO2max: one based on age-predicted maximal heart rate (HRmax) (ACSMsubmax,Fox), and the second using the actual HRmax measured during the exercise test (ACSMsubmax,measured). The measured VO2max was compared to these estimations obtained from a single exercise test. Both maximal and submaximal exercise tests significantly overestimated VO2max (ACSMmax: +9.8, p < 0.001; ACSMsubmax,Fox: +3.4, p < 0.001; ACSMsubmax,measured: +3.8 mL O2/kg∙min-1, p < 0.001). However, the submaximal estimations were closer to the measured VO2max (p < 0.001). This analysis demonstrated that the included methods overestimated the true VO2max. Nonetheless, the submaximal exercise tests provided a more accurate prediction of VO2max compared to the maximal exercise tests when using the ACSM running equation.

Aerobic power across positions - an investigation into women's soccer performance.

OBJECTIVE: The aim of the study was to discern the disparities in the aerobic capacity of female athletes occupying various positions within a soccer team, and to understand the physical characteristics of the athletes in different positions. It is critical to understand that the physical demands for players vary depending on their positions on the field, a factor that greatly influences their training and gameplay. MATERIAL AND METHODS: The study engaged a sample of 25 female soccer players, average age of 22.72 (±2.69 SD), all of whom were active participants in the Chinese Women's Super League. The sample was distributed across several playing positions, including forwards, midfielders, and defenders. To gather pertinent data on oxygen uptake, a progressive load test was administered on a treadmill, coupled with a gas analyzer to amass respiratory indices (JAEGER, Germany). RESULTS: The study revealed that there was a notable variance in the maximum oxygen uptake among players in different positions. The midfielders exhibited the highest VO2 max at 63.24±7.04 ml/kg/min, followed by the forwards who averaged at 58.92±7.70 ml/kg/min, and finally the defenders who recorded the smallest average at 55.73±4.40 ml/kg/min. CONCLUSIONS: The outcomes of this study indicate that the positional role of a player in a team correlates with their aerobic capacity. Therefore, the positional demands significantly shape the player's physical characteristics, influencing their training and gameplay. This understanding is vital for the optimal conditioning of athletes in different positions in the sport of soccer.