VO2max Research Articles

The Impact of Cardiorespiratory and Metabolic Parameters on Match Running Performance (MRP) in National-Level Football Players: A Multiple Regression Analysis

The aim of the study was to examine the association between cardiorespiratory and metabolic parameters and match running performance (MRP) in highly trained football players. The sample of participants consisted of 41 national-level football players (aged 23.20 ± 3.40 years, body height 182.00 ± 5.15 cm, and body mass 76.86 ± 6.06 kg) from the Serbian Super league. For the purposes of this research, the following measurements were applied. A maximal multistage progressive treadmill test, with a direct measurement of maximal oxygen consumption (VO2max) (using Fitmate MED, Cosmed, Rome, Italy) was conducted, alongside continuous heart rate monitoring. Capillary blood samples were taken from the hyperemic area using specific test strips, and, after sample collection, lactate concentration was immediately determined using a lactate analyzer. MRP variables were analyzed according to the BioIRC model of motion structure analysis, based on existing standards for profiling movement intensity. The results of multiple regression analysis indicated an association between cardiac parameters and total distance (R2 = 54.3%, p = 0.000), high-speed running (R2 = 46.4%, p = 0.000), and jogging (R2 = 33.6%, p = 0.004). Regression analysis revealed an association between cardiorespiratory parameters and total distance (R2 = 24.8%, p = 0.014), and high-speed running (R2 = 20%, p = 0.039). Meanwhile, no association was found between lactate concentration and running performance. The explanation for these regression analysis results is based on the observation that functional abilities represent significant potential for expressing movement performance, a crucial condition for success in football.

Assessment of Physical Fitness among School Children Aged between 11 and 14 Years in Surat City: A Cross-sectional Evaluation

Background and Purpose: Physical fitness (PF) is a powerful health indicator in children. The study aimed to measure PF and to evaluate age and gender differences in PF in school children of Surat city aged between 11 and 14 years. Methodology: The tests adopted from the EUROFIT Fitness Test Battery were used to measure the components of PF among 872 school children. Initially, body composition (height and weight) of children was measured, and body mass index (BMI) was noted. A 20-m shuttle run test to assess cardiorespiratory fitness, a hand-grip strength test to assess the strength of the hand muscles, a standing broad jump test to assess lower body explosive power, sit-ups in 30 s to evaluate abdominal muscular endurance, a sit-and-reach (SAR) test to assess flexibility, and a 10 × 5 m shuttle test to assess agility/speed were used. Results: Overall, boys performed better than girls for all the PF components except for the flexibility (SAR test), in which girls performed better. As the age increases, there would be an increase in body composition (BMI) along with increased performance on different PF components except VO2 max of 20-m shuttle run test. Conclusion: The present study concluded that a lower level of PF was noted among school children in comparison to the results of international studies, and girls are less physically fit than boys.

Effects of Surya Namaskar yoga on perceived stress, anthropometric parameters, and physical fitness in overweight and obese female university students: A randomized controlled trial

Background: Stress and sedentary lifestyles negatively impact the physical fitness of overweight and obese female university students. Physical activity has been shown to promote psychological as well as physical wellness. However, the effects of Surya Namaskar (SN) yoga on stress and physical fitness remain unclear. Objective: This study aimed to compare the physical fitness, anthropometric measures, and perceived stress between the SN yoga training program group and the control group. Methods: In a randomized controlled study, 44 overweight and obese female university students participated. For 8 weeks, the exercise group received training in SN yoga, whereas the control group was not permitted to participate in any form of exercise. At baseline and after 8 weeks of training, all participants completed the Thai Perceived Stress Scale-10 (T-PSS-10), and assessed the body mass index (BMI), waist–hip ratio, body fat percentage, maximum oxygen consumption (VO2max), and muscle strength and flexibility. We used the dependent t-test or Wilcoxon sign rank test to examine the differences between the T-PSS-10 and physical fitness within each group. The statistical differences of all parameters between the two groups were compared using an independent t-test or a Mann–Whitney U test. A p-[Formula: see text] was considered statistically significant. Results: Compared to the baseline, the SN yoga group’s post-training period had a significant increase ([Formula: see text]) in forward back flexibility, hand grip strength, leg strength, and VO2max, while a significant decrease ([Formula: see text]) in T-PSS-10 scores and BMI. In addition, we found a significant difference between the both groups in forward back flexibility and T-PSS-10 scores in the post-training period ([Formula: see text] and [Formula: see text], respectively). Conclusion: This study’s findings demonstrated that SN yoga is a useful exercise for enhancing overweight and obese female university students’ perceived stress scales and physical fitness.

A comparative analysis of the physical fitness profile of Korean women's national amateur boxers by weight category.

The purpose of this study was to examine the differences in specific physical fitness of the national amateur women's boxer. The Korean women's national amateur boxers were classified into the lightweight category (LWC, n=21) and middleweight category (MWC, n=13), and body composition (percentage body fat and body mass index) and specific physical fitness (maximal muscle strength, anaerobic power, isokinetic muscle strength, cardiopulmonary endurance) were measured. The Mann-Whitney U-test was conducted to determine the differences in the body composition and specific physical fitness in women's boxers. The percentage body fat (P=0.004) and body mass index (P<0.001) were significantly higher in the LWC compared to MWC. In addition, LWC showed significantly higher isokinetic muscle strength (P<0.001), upper anaerobic mean power (P=0.002), maximal muscle strength (P=0.003), and maximal heart rate at anaerobic threshold (P=0.029), maximal oxygen consumption (P<0.001) and the 20-m shuttle-run exercise (P=0.004) compared to MWC. In conclusion, the body fat percentage and body mass index levels among body composition were significantly higher in the MWC than in the LWC, and the constant muscle strength, maximum muscle strength, and cardiopulmonary endurance levels were significantly higher in the LWC than in the MWC. The results of this study are expected to provide useful data for planning future strategies for efficient and scientific training programs for each weight category.

Ginsenoside Rh2 shifts tumor metabolism from aerobic glycolysis to oxidative phosphorylation through regulating the HIF1-α/PDK4 axis in non-small cell lung cancer

BackgroundGinsenoside Rh2 (G-Rh2), a steroidal compound extracted from roots of ginseng, has been extensively studied in tumor therapy. However, its specific regulatory mechanism in non-small cell lung cancer (NSCLC) is not well understood. Pyruvate dehydrogenase kinase 4 (PDK4), a central regulator of cellular energy metabolism, is highly expressed in various malignant tumors. We investigated the impact of G-Rh2 on the malignant progression of NSCLC and how it regulated PDK4 to influence tumor aerobic glycolysis and mitochondrial function.MethodWe examined the inhibitory effect of G-Rh2 on NSCLC through I proliferation assay, migration assay and flow cytometry in vitro. Subsequently, we verified the ability of G-Rh2 to inhibit tumor growth and metastasis by constructing subcutaneous tumor and metastasis models in nude mice. Proteomics analysis was conducted to analyze the action pathways of G-Rh2. Additionally, we assessed glycolysis and mitochondrial function using seahorse, PET-CT, Western blot, and RT-qPCR.ResultTreatment with G-Rh2 significantly inhibited tumor proliferation and migration ability both in vitro and in vivo. Furthermore, G-Rh2 inhibited the tumor’s aerobic glycolytic capacity, including glucose uptake and lactate production, through the HIF1-α/PDK4 pathway. Overexpression of PDK4 demonstrated that G-Rh2 targeted the inhibition of PDK4 expression, thereby restoring mitochondrial function, promoting reactive oxygen species (ROS) accumulation, and inducing apoptosis. When combined with sodium dichloroacetate, a PDK inhibitor, it complemented the inhibitory capacity of PDKs, acting synergistically as a detoxifier.ConclusionG-Rh2 could target and down-regulate the expression of HIF-1α, resulting in decreased expression of glycolytic enzymes and inhibition of aerobic glycolysis in tumors. Additionally, by directly targeting mitochondrial PDK, it elevated mitochondrial oxidative phosphorylation and enhanced ROS accumulation, thereby promoting tumor cells to undergo normal apoptotic processes.

Changes in running economy and attainable maximal oxygen consumption in response to prolonged running: The impact of training status.

During prolonged running at moderate-to-high intensity, running economy (RE) deteriorates and attainable maximal oxygen consumption (VO2max) decreases. Whether these changes appear similarly in trained and untrained runners exercising at the same relative intensity is not clear. We recruited 10 trained runners (TR) and 10 active adults (AA), and compared RE and attainable VO2max before and after 1 h of running at 70% of VO2max. Submaximal VO2 increased more (p = 0.019) in AA (0.20 ± 0.13 L min-1) than in TR (0.07 ± 0.05 L min-1). Attainable VO2max decreased in AA (-0.21 ± 0.15 L min-1, p = 0.002), but remained unchanged in TR (-0.05 ± 0.10 L min-1, p = 0.18). Relative intensity (i.e., VO2/attainable VO2max), increased more (p = 0.001) in AA (8.3 ± 4.4%) than in TR (2.6 ± 1.9%). These results demonstrate that the ability to resist changes in RE and VO2max following prolonged running is superior in trained versus untrained runners, when exercising at the same relative intensity.

Platelet Bioenergetics and Associations With Delirium and Coma in Patients With Sepsis: A Prospective Cohort Study

BackgroundAcute brain dysfunction during sepsis, which manifests as delirium or coma, is common and associated with multiple adverse outcomes including longer periods of mechanical ventilation, prolonged hospital stays, and increased mortality. Delirium and coma during sepsis may be manifestations of alteration in systemic metabolism. Since access to brain mitochondrial is a limiting factor, measurement of peripheral platelet bioenergetics offers a potential opportunity to understand metabolic changes associated with acute brain dysfunction during sepsis. Research QuestionAre altered platelet mitochondrial bioenergetics associated with acute brain dysfunction during sepsis? Study Design and MethodsWe assessed participants with critical illness in the ICU for the presence of delirium or coma via validated assessment measures. Blood samples were collected and processed to isolate and measure platelet mitochondrial oxygen consumption. We used Seahorse extracellular flux to directly measure baseline, proton leak, maximal oxygen consumption rate, and extracellular acidification rate. We calculated ATP-linked, spare respiratory capacity, and non-mitochondrial oxygen consumption rate from the measured values. ResultsMaximal oxygen consumption was highest in patients with coma, as was spare respiratory capacity and ECAR in unadjusted analysis. After adjusting for age, sedation, modified Sequential Organ Failure Assessment (SOFA) without the neurological component, and pre-existing cognitive function, increased spare respiratory capacity remained associated with coma. Delirium was not associated with any platelet mitochondrial bioenergetics. InterpretationIn this single-center, exploratory, prospective cohort study, we found increased platelet mitochondrial spare respiratory capacity was associated with coma in patients with sepsis. Future studies powered to determine any relationship between delirium and mitochondrial respiration bioenergetics are needed.

The metabolome as a diagnostic for maximal aerobic capacity during exercise in type 1 diabetes

Aims/hypothesisOur aim was to characterise the in-depth metabolic response to aerobic exercise and the impact of residual pancreatic beta cell function in type 1 diabetes. We also aimed to use the metabolome to distinguish individuals with type 1 diabetes with reduced maximal aerobic capacity in exercise defined by V˙O2peak\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\dot{V}{\ ext{O}}_{\ ext{2peak}}$$\\end{document}.MethodsThirty participants with type 1 diabetes (≥3 years duration) and 30 control participants were recruited. Groups did not differ in age or sex. After quantification of peak stimulated C-peptide, participants were categorised into those with undetectable (<3 pmol/l), low (3–200 pmol/l) or high (>200 pmol/l) residual beta cell function. Maximal aerobic capacity was assessed by V˙O2peak\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\dot{V}{\ ext{O}}_{\ ext{2peak}}$$\\end{document} test and did not differ between control and type 1 diabetes groups. All participants completed 45 min of incline treadmill walking (60% V˙O2peak\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\dot{V}{\ ext{O}}_{\ ext{2peak}}$$\\end{document}) with venous blood taken prior to exercise, immediately post exercise and after 60 min recovery. Serum was analysed using targeted metabolomics. Metabolomic data were analysed by multivariate statistics to define the metabolic phenotype of exercise in type 1 diabetes. Receiver operating characteristic (ROC) curves were used to identify circulating metabolomic markers of maximal aerobic capacity (V˙O2peak\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\dot{V}{\ ext{O}}_{\ ext{2peak}}$$\\end{document}) during exercise in health and type 1 diabetes.ResultsMaximal aerobic capacity (V˙O2peak\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\dot{V}{\ ext{O}}_{\ ext{2peak}}$$\\end{document}) inversely correlated with HbA1c in the type 1 diabetes group (r2=0.17, p=0.024). Higher resting serum tricarboxylic acid cycle metabolites malic acid (fold change 1.4, p=0.001) and lactate (fold change 1.22, p=1.23×10−5) differentiated people with type 1 diabetes. Higher serum acylcarnitines (AC) (AC C14:1, F value=12.25, p=0.001345; AC C12, F value=11.055, p=0.0018) were unique to the metabolic response to exercise in people with type 1 diabetes. C-peptide status differentially affected metabolic responses in serum ACs during exercise (AC C18:1, leverage 0.066; squared prediction error 3.07). The malic acid/pyruvate ratio in rested serum was diagnostic for maximal aerobic capacity (V˙O2peak\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\dot{V}{\ ext{O}}_{\ ext{2peak}}$$\\end{document}) in people with type 1 diabetes (ROC curve AUC 0.867 [95% CI 0.716, 0.956]).Conclusions/interpretationThe serum metabolome distinguishes high and low maximal aerobic capacity and has diagnostic potential for facilitating personalised medicine approaches to manage aerobic exercise and fitness in type 1 diabetes.Graphical

Determination of speed and assessment of conditioning in horses submitted to a lactate minimum test-alternative approaches.

The maximal lactate steady state (MLSS) is a well-known gold standard method for determining the aerobic capacity of athletic horses. Owing to its high cost and complex execution, there is a search for standardized exercise tests that can predict this value in a single session. One of the methods described for this purpose is the lactate minimum test (LMT), which could be more accurate despite being adequate to predict MLSS. This study aimed to examine the impact of training on the speed corresponding to lactate minimum speed (LMS) and to apply new mathematical methods to evaluate the fitness level of horses based on the curve obtained by the LMT. Ten Arabian horses underwent a 6-week training program based on LMS calculated by second-degree polynomial regression (LMSP). In addition, the LMS was also determined by visual inspection (LMSV), bi-segmented linear regression (LMSBI) and spline regression (LMSS). From the curve obtained during the LMT, it was possible to calculate angles α, β and ω, as well as the total area under the curve (AUCTOTAL) before (AUCPRELMS) and after (AUCPOSLMS) the LMS. The methods for determining the LMS were evaluated by ANOVA, intraclass correlation coefficient (ICC) and effect size (ES) by Cohen's d test. The Pearson correlation coefficient (r) between the proposed LMS determination methods and other mathematical methods was also calculated. Despite showing a good correlation (ICC >0.7), the LMS determination methods differed from each other (p < 0.05), albeit without a significant difference resulting from conditioning. There were reductions in α:β ratio, angle α, and AUCPOSTLMS, with the latter indicating lower lactate accumulation in the incremental phase of LMT after conditioning, in addition to an improvement in the animals' aerobic capacity. Considering that the most common methods for determining the LMS are applicable yet with low sensitivity for conditioning assessment, the approaches proposed herein can aid in analyzing the aerobic capacity of horses subjected to LMT. The mathematical models presented in this paper have the potential to be applied in human lactate-guided training program trials with a comparable study basis.

Unlocking the Science of Physical Endurance: Training Techniques and Biological Factors

This study examines the many elements influencing endurance performance in university students, including training routines, psychological fortitude, hereditary tendencies, and environmental adjustments. Data was gathered from 38 university students engaged in endurance sports using a descriptive methodology. The results reveal a significant commitment to endurance training since individuals typically participate in four sessions each week, each lasting around 60 minutes. Psychological resilience plays a significant role, with 82% of participants showing strong levels of intrinsic motivation and 74% displaying mental toughness in overcoming obstacles. 37% of participants have a family history of endurance performance, while 29% are interested in genetic testing, showing differing views on hereditary effects on performance. Performance outcomes are greatly impacted by environmental conditions, such as altitude training (42%), and heat acclimatisation (63%), which are often used tactics. The physiological examinations show an average VO2 max of 50 ml/kg/min, along with a muscle fibre composition consisting of 55% slow-twitch fibres and 45% fast-twitch fibres. The results highlight the intricate nature of elements influencing endurance performance in university students, emphasising the need for customised support systems. Universities can enhance performance outcomes and foster comprehensive athlete development by considering physiological, psychological, genetic, and environmental factors. This study enhances comprehension of the complex aspects of endurance performance in university students, offering valuable insights for improving athletic training and support programmes. Coaching recommendations should customise training programmes based on individual athlete requirements, utilising strong intrinsic motivation and mental resilience to create a favourable training atmosphere and enhance performance results. Keywords: Endurance Performance, University Students, Psychological Resilience.

Cheese positively affects serum osteocalcin levels, bone turnover markers and bone mineral density in cross-country skiers: a dose-response study

Background: Vitamin K2-rich Jarlsberg Cheese is demonstrated to increase Osteocalcin and bone turnover markers in fertile women. The impact on endurance-trained young cross-country skiers (XCS) with elevated bone turnover remains unclear. Purpose of study was to estimate the optimal daily efficacy dose of Jarlsberg cheese to increase serum Osteocalcin level in young female and male XCS and estimate the Jarlsberg effect on bone turnover markers (BTMs) and bone mineral density (BMD). Methods: In a parallel group study consisting of three design levels, 10 female and 10 male XCS were included, using Response Surface Pathway design. Blood samples were taken at each level for measurements of Osteocalcin, vitamin K2, BTMs and other biochemical parameters. Resting metabolic rate (RMR), BMD, VO2max and muscle strength were measured at start and at the end of the study. Results: The Osteocalcin development with increasing dose of Jarlsberg cheese was almost parallel in both sexes. These variables were reduced significantly from baseline during the first two design levels but increased above baseline by the end of the study. BTMs decreased significantly during the first and second level but increased during the third level. Total and L1-L4 BMD, s-phosphate, s-urea, RMR, muscle strength and Peak VO2 increased significantly while s-calcium and s-magnesium decreased. Conclusions: Estimated OED of Jarlsberg cheese was 73 and 84 g/day for females and male athletes, respectively. The development in OC, BTMs and BMD suggest an antiresorptive and perhaps anabolic effect of Jarlsberg Cheese on bone tissue. VO2 max, RMR and muscular strength development indicated an anabolic situation.

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.

Does Short-Term Speed Endurance Soccer Training Improve Physical Performance?

Objectives. This study is aimed at analyzing the impact of short-term Speed Endurance Soccer Training (SEST) training on the physical performance of young soccer players. Materials and methods. The true experiment method was used in this study. The study population comprised a total of 122 individuals. Furthermore, by using random sampling techniques, a sample of 30 persons was selected with an average age of 15.2 ± 0.81 years, height 168.1 ± 4.82 cm, weight 57.85 ± 11.93 kg, and BMI 20.34 ± 3.37. Physical performance instruments included the Running Based Anaerobic Sprint Test (RAST), Yo-Yo intermittent test level 1, 20-meter sprint, and standing broad jump test. The study used the paired t-test to evaluate the effect of each group and the independent samples t-test to compare the improvement in the experimental (SEST) and control groups. Statistical significance was set at p &lt; 0.05. Results. The paired t-test showed significant differences between the pretest and post-test in the SEST group in anaerobic (p = .000, Δ% = 8.4), aerobic (p = .000, Δ% = 7.48), and speed (p = .000, Δ% = 3.39) capacities. Meanwhile, there were no considerable differences in the variables for the control group. According to the independent t-test results, a significant difference in effect between the SEST group and the CTRL group was revealed. The SEST group demonstrated marked differences in anaerobic, aerobic and speed variables with a p-value = 0.000. Conclusions. The study reveals that short-term Speed Endurance Soccer Training contributes to enhancing the physical performance of soccer players. However, caution should be exercised regarding the potential risk of hamstring injury in individuals with unprepared muscles.

Effects of Physical Activity on Quality of Life of Pregnant Women with Overweight or Obesity: A Systematic Review

There is evidence that the quality of life and mental health of pregnant women change during pregnancy. To evaluate the impact of physical activity on the quality of life and mental health of pregnant women with obesity or overweight, a systematic review was performed using six electronic databases (PubMed, Cochrane (CENTRAL), ScienceDirect, Scielo, BVS and PEDro). In total, 205 articles were collected, and after screening in accordance with the PRISMA declaration, six randomized clinical trials were selected. Methodological quality was assessed using the Cochrane RoB2 tool and a narrative synthesis of the results was performed. Physical activity interventions did not demonstrate statistically significant results on the quality of life and mental health of pregnant women with obesity or overweight. The effects of physical activity during pregnancy for women with obesity or overweight are varied due to the diversity of interventions implemented. Nonetheless, a discernible positive association emerges between stringent adherence to the prescribed physical activity regimen and enhanced physical well-being, weight management, and heightened aerobic capacity. In order to ascertain more definitive conclusions, rigorous clinical trials are needed that take into account the heterogeneity of interventions and ensure adequate adherence to the protocol.

Association between heart rate variability and cardiorespiratory fitness in individuals with type 2 diabetes mellitus

Background: Type 2 Diabetes Mellitus (T2DM) is associated with cardiovascular risk, which is partly due to autonomic dysfunction and decreased cardiorespiratory fitness. This study examines the relationship between heart rate variability (HRV) and maximal oxygen uptake (VO2max) in T2DM patients to understand their interconnected impacts on autonomic and aerobic functions. Methods: In a cross-sectional study, 77 T2DM patients underwent HRV and VO2max assessments using standard protocols. HRV metrics were analysed in conjunction with VO2max, measured through direct breath-by-breath analysis. Pearson's correlation coefficient was used to investigate the relationships between HRV indices and VO2max. Results: VO2max showed strong positive correlations with RMSSD (r = 0.89, p &lt; .001), HF (r = 0.54, p &lt; .001), and pNN50% (r = 0.52, p &lt; .001), indicating higher parasympathetic activity with improved cardiorespiratory fitness. Negative correlations with LF (r = -0.60, p &lt; .001) and the LF/HF ratio (r = -0.39, p &lt; .001) suggested that better fitness levels lead to sympathetic withdrawal and a more favourable autonomic balance. Moderate positive correlations with SDNN (r = 0.46, p &lt; .001) and TP (r = 0.58, p &lt; .001) further suggested that overall autonomic modulation is enhanced with increased cardiorespiratory fitness. Conclusion: This study substantiates a significant correlation between HRV and VO2max in individuals with T2DM, highlighting the intricate relationship between autonomic function and aerobic capacity. These findings suggest that enhancing cardiorespiratory fitness may improve autonomic balance, offering potential avenues for mitigating cardiovascular risk in the T2DM population.

Exercise Training Attenuates the Muscle Mitochondria Genomic Response to Bed Rest.

Exercise training during the National Aeronautics and Space Administration (NASA) 70-day bed rest study effectively counteracted the decline in aerobic capacity, muscle mass, strength, and endurance. We aimed to characterize the genomic response of the participants' vastus lateralis (VL) on day 64 of bed rest with and without exercise countermeasures. Twenty-two healthy young males were randomized into three groups: 1) bed rest only (n = 7), 2) bed rest + aerobic (6 d/wk) and resistance training (3 d/wk) on standard equipment (n = 7), and 3) bed rest + aerobic and resistance training using a flywheel device (n = 8). The VL gene and microRNA microarrays were analyzed using GeneSpring GX 14.9.1. Bed rest significantly altered the expression of 2113 annotated genes in at least one out of the three study groups (fold change (FC) > 1.2; P < 0.05). Interaction analysis revealed that exercise attenuated the bed rest effect of 511 annotated genes (FC 1.2, P < 0.05). In the bed rest only group, a predominant downregulation of genes was observed while in the two exercise groups there was a notable attenuation or reversal of this effect, with no significant differences between the two exercise modalities. Enrichment analysis identified functional categories and gene pathways, many of them related to the mitochondria. Additionally, bed rest significantly altered the expression of 35 microRNAs (FC > 1.2, P < 0.05) with no difference between the three groups. Twelve are known to regulate some of the mitochondrial-related genes that were altered following bed rest. Mitochondrial gene expression was a significant component of the molecular response to long-term bed rest. While exercise attenuated the FC in the downregulation of many genes, it did not completely counteract all the molecular consequences.

Acute interval running induces greater excess post-exercise oxygen consumption and lipid oxidation than isocaloric continuous running in men with obesity

Studies seem to show that high-intensity interval training (HIIT) is a more time-efficient protocol for weight loss, compared with moderate-intensity continuous training (MICT). Our aim was to compare the acute effects of energy expenditure (EE) matched HIIT vs. MICT on excess post-exercise oxygen consumption (EPOC) and substrate metabolism in male college students with obesity. Twenty-one untrained male college students (age, 22 ± 3 years; body fat, 28.4 ± 4.5%) completed two acute interventions (~ 300 kcal) on a treadmill in a randomized order: (1) HIIT: 3 min bouts at 90% of maximal oxygen uptake (VO2max) with 2 min of recovery at 25% of VO2max; (2) MICT: 60% of VO2max continuous training. EPOC and substrate metabolism were measured by indirect calorimetry during and 30 min after exercise. Results showed that EPOC was higher after HIIT (66.20 ± 14.36 kcal) compared to MICT (53.91 ± 12.63 kcal, p = 0.045), especially in the first 10 min after exercise (HIIT: 45.91 ± 9.64 kcal and MICT: 34.39 ± 7.22 kcal, p = 0.041). Lipid oxidation rate was higher after HIIT (1.01 ± 0.43 mg/kg/min) compared to MICT (0.76 ± 0.46 mg/kg/min, p = 0.003). Moreover, the percentage of energy from lipid was higher after HIIT (37.94 ± 14.21%) compared to MICT (30.09 ± 13.54%, p = 0.020). We conclude that HIIT results in greater total EE and EPOC, as well as higher percentage of energy from lipid during EPOC than EE matched MICT in male college students with obesity.

Prevalence of Different Types of Eating Disorder in Different Endurance Sports and its Impact on Performance: A Narrative Review

Endurance sports have shown prominent effects in aerobic capacity, cardio-protection, prevention or treatment of diabetic mellitus, athletic body composition and bone density. Despite of these positive effects, these sports may leads to risk factor of eating disorder. It has been found in several studies that athletes are more prone to eating disorder (ED) than the non athletic population. Thus the aim and objective of this review is to critically analyze the literature to evaluate different types of eating disorder among athletes and its impact on their performance among endurance athletes. The significance of this review is to provide information about further exploration in eating disorder athletes so that it may hopefully help clinicians and physiotherapist in planning individualized exercise programs that would be beneficial at improving outcomes in these sports person. Result suggested that antigravitational sports are at higher risk of ED when compared with endurance sports whereas endurance sports athletes are at more risk when compared with ball sports or triathletes. It has be also found out that initially ED may result in performance but later it will leads to low performance because athletes with EDs will physiological and psychological disorders. KEYWORDS: Eating Disorder OR Anorexia OR Bulimia OR Endurance Sports OR Athlete OR Performance

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.

Metabolic demands of a simulated smoke-diving drill

The main goal of this study was to update the Finnish smoke-diving drill (FSDD) and to measure the physical strain of and recovery from the drill. Furthermore, the aim was to compare the physical strain of contract and professional firefighters and effect of floor materials. The associations between aerobic capacity and physical strain were also studied. The updates made included an added hose pull task and updating the equipment used. Heart rate (HR), oxygen consumption (V̇O2), and blood lactate concentration ([La-]) of 32 professional and 5 contract firefighters were measured before, during, and 10 and 30 min after the updated drill. The mean HR during the drill was 78% and V̇O2 59% of maximum. HR and [La-] had not recovered to baseline levels after 30-minute recovery period. Physical strain was higher among contract firefighters and [La-] accumulation on rough floor surfaces. Better aerobic capacity was associated with reduced physical strain.