New Approaches in Exercise Physiology

Abstract Purpose: Adolescent obesity is associated with early alterations in lipid metabolism and increased cardiovascular risk. Atherogenic indices such as Castelli Risk Index I (CRI-I), Castelli Risk Index II (CRI-II), Atherogenic Index of Plasma (AIP), and Atherogenic Coefficient (AC) are considered sensitive predictors of cardiovascular disease beyond traditional lipid measures. Therefore, the present study aimed to investigate the effect of 10 weeks of futsal training on selected atherogenic indices in inactive obese adolescent boys. Method: This quasi-experimental study was conducted using a pretest–posttest design with a control group. Thirty inactive obese boys aged 13–17 years were randomly assigned to an experimental group (futsal training, n = 15) and a control group (n = 15). The experimental group participated in a structured 10-week futsal training program, while the control group maintained their usual daily activities. Atherogenic indices were calculated from fasting lipid profiles measured before and after the intervention. Data were analyzed using paired-samples t-tests, independent-samples t-tests, and ANCOVA. Results: Within-group analysis revealed significant reductions in the experimental group for CRI-I (p=0.021), CRI-II (p=0.012), AIP (p=0.011), and AC (p=0.032), whereas no significant changes were observed in the control group (p>0.05). Between-group comparisons at posttest showed significant differences favoring the experimental group for CRI-I (p=0.013), CRI-II (p=0.024), AIP (p=0.041), and AC (p=0.032). These differences remained significant after adjusting for baseline values. Conclusion: Ten weeks of structured futsal training significantly improved atherogenic risk indices in inactive obese adolescent boys. Futsal may therefore serve as an effective, practical, and non-pharmacological strategy to reduce early cardiovascular risk in this population.

Abstract Background: Exerkines, bioactive molecules released during physical activity, are key mediators of exercise-related health benefits, including disease prevention, health promotion, and enhanced resilience. Despite their significance, no bibliometric analysis of exerkine research has been conducted. Method: This study aims to provide a comprehensive bibliometric overview of exerkine studies from 2016 to 2024, using the Web of Science database. We analyzed 131 publications through the Bibliometrix R package and VOSviewer to explore publication trends, key contributors, and research hotspots. Results: Results show a 55.39% annual growth rate, with 87 journals publishing in this field, led by Frontiers in Physiology. China and the USA contributed the most publications. High-frequency keywords included skeletal muscle, physical activity, and insulin resistance, reflecting core research areas. Ewa Ziemann was the most prolific author. Conclusion: This analysis highlights global research trends, influential journals, and emerging themes, offering a foundation for future investigations. By mapping the current state and potential directions of exerkine research, this study supports researchers in advancing knowledge and optimizing exercise-based interventions.  

Abstract Purpose: The purpose of the present study was to investigate the acute effects of static stretching, dynamic stretching, and foam rolling on knee range of motion and joint position sense in healthy male adolescents. Method: In a quasi-experimental study with a pretest–posttest design, 40 male adolescents (12–17 years) were randomly assigned to static stretching, dynamic stretching, foam rolling, and control groups. Knee ROM and JPS were measured before and immediately after the intervention. Data were analyzed using repeated-measures ANOVA. Results: No significant interaction effect was found between time and group for ROM (p > 0.05) or JPS (p > 0.05). Although a significant main effect of group was observed for ROM (p < 0.001), no significant changes were found in JPS. Conclusion: A single session of static stretching, dynamic stretching, and foam rolling did not significantly affect knee joint ROM or JPS in healthy adolescents.

Abstract Purpose: Oxidative stress contributes to many chronic diseases. Although physical activity promotes health, its effects on lipid peroxidation (MDA) and total antioxidant status (TAS) remain unclear. This meta‑analysis quantitatively synthesized the effects of physical activity on MDA and TAS in humans. Method: This systematic review and meta‑analysis was conducted in accordance with the PRISMA 2020 guideline and registered with PROSPERO (CRD420251144711). A systematic literature search was performed across PubMed, Scopus, and Web of Science covering the period from January 2000 to November 2025. Human studies evaluating the impact of either acute or chronic physical activity on MDA and TAS concentrations were included. Pooled effect sizes were estimated using a random‑effects model, and standardized mean differences (SMD) with 95% CI were calculated. Heterogeneity was assessed using the I² statistic.
Results: Out of 620 initially identified records, 21 studies met the eligibility criteria, of which 10 and 4 were suitable for meta‑analysis of MDA and TAS, respectively. Physical activity resulted in a significant reduction in MDA levels (SMD = –1.02; 95% CI: –1.95 to –0.09; p = 0.032). Moreover, physical activity led to a highly significant increase in TAS (SMD = +0.76; 95% CI: 0.38 to 1.15; p < 0.001). Heterogeneity was substantial for both analyses (I² = 94.6% for each). Subgroup analyses revealed that the decline in MDA was more pronounced among individuals with a body mass index above 25 (BMI > 25) and those younger than 50 years (p < 0.05). Conclusion: Regular, structured physical activity effectively lowers lipid peroxidation and enhances total antioxidant capacity in humans. These findings strengthen the role of physical activity as an effective non‑pharmacological strategy for modulating systemic oxidative stress and reducing the risk of related diseases.

Abstract Objective: Multiple sclerosis (MS) is a chronic neurological disease that predominantly affects women and is associated with reduced muscular strength, increased fatigue, and impaired quality of life. Resistance training has been proposed as a safe and effective non-pharmacological intervention; however, evidence focusing specifically on women with MS remains limited. Therefore, the present study aimed to examine the effects of eight weeks of resistance training on quality of life, muscular strength, fatigue, and body mass index in women with MS.
Methods:
This quasi-experimental study used a pretest–posttest design with a control group. Thirty women with MS were randomly assigned to a resistance training group (n=15) or a control group (n=15). The experimental group performed supervised resistance training three times per week for eight weeks, while the control group continued their usual activities. Outcome measures were assessed before and after the intervention. Paired and independent samples t-tests were applied for data analysis.
Results:
The resistance training group showed significant improvements in quality of life (p=0.001) and muscular strength (p<0.001), along with a significant reduction in fatigue (p=0.002). No significant change was observed in body mass index (p=0.42). No significant changes were found in the control group (p>0.05). Between-group comparisons at posttest favored the resistance training group for quality of life (p=0.008), muscular strength (p=0.004), and fatigue (p=0.006(.
Conclusion:
Eight weeks of resistance training significantly improved quality of life and muscular strength and reduced fatigue in women with multiple sclerosis, supporting its inclusion in rehabilitation programs.

Abstract Background: Sleep disorders significantly impact physical and mental health, particularly among adolescents, by disrupting immune and inflammatory systems. This study aimed to evaluate and compare the efficacy of sleep hygiene, high-intensity interval training (HIIT), and their combined effect on sleep quality and serum levels of inflammatory markers (IL-1β, IgA, and cortisol) in adolescent girls with sleep disorders. A randomized controlled trial (RCT) with a pre-test and post-test design was employed. The participants, consisting of adolescent girls diagnosed with sleep disturbances, were assigned to intervention groups including sleep hygiene, HIIT program, and a combined group (HIIT + sleep hygiene). The HIIT protocol involved repeated bouts of intense activity near maximal oxygen consumption (VO2max), while the sleep hygiene protocol focused on increasing nocturnal sleep duration. Serum levels of IL-1β, IgA, and cortisol were measured as primary inflammatory and stress indicators. Preliminary analysis suggests that while both HIIT and sleep hygiene independently improve sleep quality, the combination of physical activity and increased sleep duration shows a more significant synergistic effect on modulating inflammatory responses. Specifically, regular exercise combined with adequate recovery through sleep extension is expected to lower cortisol and IL-1β levels while improving immune function as reflected by IgA levels.Integrating physical exercise with sleep hygiene not only improves sleep quality but also helps mitigate the systemic inflammation associated with chronic sleep deprivation, offering a holistic strategy for enhancing adolescent health.

Abstract Abstract
Breast cancer survivors (BCS) frequently experience increased Fear of Falling (FOD), which restricts physical activity and compromises functional independence. While High-Intensity Interval Training (HIIT) is recommended to improve cardiorespiratory fitness and reduce cancer-related fatigue, its acute physiological stress may disrupt sleep architecture, potentially exacerbating FOD.
This study investigated the day-to-day correlation between qualitative sleep parameters (measured by a smartwatch) and FOD intensity in post-HIIT days in a breast cancer survivor.
A longitudinal case study was conducted over four weeks with a 73-year-old female survivor. Sleep metrics (efficiency, deep sleep, awakenings) were objectively tracked using an Apple Watch Series 6, while FOD was assessed daily using the Falls Efficacy Scale-International (FES-I). Data were analyzed using Pearson correlation coefficients.
Results indicated a significant negative correlation between sleep efficiency and FOD (r=−0.65,p<0.01). Days with sleep efficiency below 75% showed significantly higher FOD scores (Mean = 32) compared to days with efficiency above 80% (Mean = 24). Furthermore, HIIT interventions led to improved resting heart rate and reduced RPE, coinciding with a gradual decline in FOD from 28.5 to 23.8 over four weeks.
These exploratory findings suggest that sleep quality, particularly sleep efficiency, may be associated with FOD intensity in breast cancer survivors. The results highlight the potential value of personalized HIIT protocols, which account for daily sleep recovery status, in supporting psychological safety and physical engagement. Integrating wearable technology into clinical rehabilitation may allow for real-time adjustment of training loads to optimize both physiological adaptation and psychological well-being in this vulnerable population.

Abstract Background: Sleep quality and anxiety regulation are essential for recovery, cognitive function, and readiness in military cadets. High-intensity interval training (HIIT) and melatonin may influence sleep and psychological responses, but their combined effects remain unclear.

Purpose: This study examined the isolated and combined effects of four weeks of HIIT and melatonin supplementation on sleep quality and anxiety in military cadets.

Method: In this quasi-experimental pretest-posttest study, 31 male military cadets were allocated to Melatonin (n = 10), HIIT (n = 10), and HIIT + Melatonin (n = 11) groups. Training groups performed supervised running-based HIIT three times weekly for four weeks. Supplementation groups consumed 5 mg melatonin nightly at 21:00. Sleep quality and anxiety were assessed using the Pittsburgh Sleep Quality Index (PSQI) and Beck Anxiety Inventory (BAI). Paired-sample t-tests and ANCOVA were used for statistical analysis.

Results: PSQI scores improved significantly in all groups (P < 0.01), with the largest within-group improvement observed in the HIIT + Melatonin group (P = 0.001, Cohen's d = 1.33). Anxiety scores also decreased significantly in all groups (P < 0.05), with the largest reduction observed in the combined group (P = 0.002, Cohen's d = 1.25). ANCOVA demonstrated significant between-group differences in adjusted post-test PSQI and BAI scores after controlling for baseline values.

Conclusions/Implications: HIIT and melatonin improved sleep quality and reduced anxiety in military cadets. The combined intervention demonstrated the largest within-group improvement and may represent a useful recovery-oriented strategy for military training programs.

Abstract Methods: In this randomized, double-blind, placebo-controlled trial, 22 inactive older men aged 65–85 years were assigned to suspension training plus creatine (TRX+Cr; n = 11) or suspension training plus placebo (TRX+Pla; n = 11). Both groups completed a supervised 6-week suspension training program. The TRX+Cr group received creatine monohydrate at 0.3 g·kg⁻¹·day⁻¹ throughout the intervention, whereas the TRX+Pla group received placebo. Outcomes included appendicular skeletal muscle mass index (ASMI), serum myostatin, follistatin, insulin-like growth factor-1 (IGF-1), vitamin D, handgrip strength, five-times sit-to-stand (5xSTS), and Short Physical Performance Battery (SPPB). Between-group differences were analyzed using ANCOVA adjusted for baseline values.

Results: Creatine supplementation produced a greater reduction in circulating myostatin compared with placebo (p < 0.001). A significant between-group difference was also observed for follistatin (p = 0.002); however, this reflected a decrease in the creatine group and should not be interpreted as a favorable anabolic response. ASMI did not differ significantly between groups (p = 0.051). No significant between-group differences were observed for IGF-1, vitamin D, handgrip strength, 5xSTS, or SPPB.

Conclusion: Creatine supplementation during 6 weeks of suspension training reduced circulating myostatin in inactive older men, but this biomarker response was not accompanied by statistically significant additional improvements in ASMI, physical function, IGF-1, or vitamin D.

Abstract Purpose: This study investigated the acute serum responses of decorin and interleukin-1β (IL-1β) and the effects of 8 weeks of Myo-reps, traditional, and combined resistance training on rectus femoris muscle thickness and lower-body strength in men.
Methods: Thirty-six resistance-trained men (26.03 ± 4.22 years; BMI: 24.83 ± 3.05 kg/m²) were randomly assigned to traditional, Myo-reps, or combined training. Participants completed an 8-week program (3 sessions/week) with standardized volume and progressive intensity (75–85% 1RM). Serum decorin and IL-1β were measured before and immediately after the third training session during week 1. Rectus femoris muscle thickness was assessed by ultrasonography, and hack squat one-repetition maximum was measured before and after training. Data were analyzed using paired-samples t-tests and ANCOVA (p < 0.05).
Results: No between-group differences were found for serum decorin (p = 0.81) or IL-1β (p = 0.67). Decorin decreased only in the traditional group (p = 0.03), whereas IL-1β remained unchanged in all groups. Rectus femoris muscle thickness increased in the Myo-reps (p = 0.02) and combined (p = 0.001) groups, but not in the traditional group (p = 0.07). Muscle thickness differed between groups (p = 0.01), with greater increases in the combined than the traditional group (p = 0.01). Hack squat strength improved in all groups (p = 0.001), with no between-group differences (p = 0.51).
Conclusion: Combined Myo-reps and traditional resistance training produced greater increases in rectus femoris thickness than traditional resistance training alone without altering acute decorin or IL-1β responses. All protocols similarly improved lower-body strength.

Abstract Background: This study compared the effects of 8 weeks of continuous aerobic exercise (CAE) versus high-intensity interval training (HIIT) on fasting glucose, insulin, HOMA-IR, and hepatic ANGPTL4 expression in fructose/STZ induced insulin resistant rats.
Methods: Thirty-two insulin-resistant female Wistar rats were randomized into healthy control (HC), insulin-resistant control (IR-C), insulin-resistant + CAE (IR-CAE), and insulin-resistant + HIIT (IR-HIIT). IR-CAE performed 8 weeks (5×/wk) progressive running at 50–60% VO₂max (speed: 12→20 m/min; duration: 12→54 min/day; incline: 5°→15°). IR-HIIT performed the same duration/frequency with 3-min high-intensity intervals at 90–95% VO₂max (speed: 15–20→40 m/min; intervals: 2→6/session; 3-min active recovery; same incline progression). All sessions included 5-min warm-up/cool-down at 10 m/min. Fasting glucose, insulin, HOMA-IR, and hepatic ANGPTL4 mRNA (real-time RT-PCR) were measured 48h post-last session.
Results: Both IR-CAE and IR-HIIT similarly reduced fasting glucose and HOMA-IR compared to IR-C (P

Abstract Aging is associated with progressive declines in skeletal muscle mass, strength, and mitochondrial function, contributing to sarcopenia and physical frailty. Increasing evidence suggests that the gut microbiota may influence musculoskeletal aging through its regulation of metabolic homeostasis, inflammation, and anabolic signaling. The gut–muscle–mitochondria axis has emerged as a conceptual framework linking microbial-derived metabolites to skeletal muscle physiology and cellular energy metabolism. Within this framework, microbial metabolites such as short chain fatty acids may influence muscle protein turnover, mitochondrial biogenesis, and systemic metabolic regulation. Exercise, the most effective intervention for preserving muscle function in older adults, has been shown to modulate gut microbiota composition, enhancing short-chain fatty acid production and promoting mitochondrial adaptations. Exercise-induced shifts in microbial diversity may also support anti-inflammatory pathways and improve gut barrier integrity. These mechanisms may contribute to improved insulin sensitivity, anabolic signaling, and muscle metabolic efficiency, thereby supporting muscle maintenance during aging. Despite promising mechanistic insights, most available evidence derives from animal or observational studies, and causal relationships in humans remain to be established. Further longitudinal and interventional research is required to clarify the clinical relevance of microbiota modulation as a complementary strategy for promoting healthy musculoskeletal aging and preventing age-related functional decline.