Search Results (427)

Aging is associated with complex immune dysfunction that contributes to the onset and progression of the “geriatric giants”, including frailty, sarcopenia, cognitive decline, falls, and incontinence. Central to these conditions is immunosenescence, marked by thymic involution, the loss of naïve T cells, T-cell exhaustion, impaired B-cell class switch recombination, and increased autoreactivity. Concurrently, innate immunity deteriorates due to macrophage, neutrophil, and NK cell dysfunction, while chronic low-grade inflammation—or “inflammaging”—amplifies systemic decline. Key molecular pathways such as NF-κB, mTOR, and the NLRP3 inflammasome mediate immune aging, interacting with oxidative stress, mitochondrial dysfunction, and epigenetic modifications. These processes not only impair infection control and vaccine responsiveness but also promote tissue degeneration and multimorbidity. This review explores emerging interventions—ranging from senolytics and immunonutrition to microbiome-targeted therapies and exercise—that may restore immune homeostasis and extend healthspan. Despite advances, challenges remain in translating immunological insights into clinical strategies tailored to older adults. Standardization in microbiome trials and safety optimization in senolytic therapies are critical next steps. Integrating geroscience into clinical care could help to mitigate the burden of aging-related diseases by targeting fundamental drivers of immune dysfunction. Full article

According to the World Health Organization (WHO), a healthy lifestyle is defined as a way of living that lowers the risk of becoming seriously ill or dying prematurely. Physical activity, as a well-known contributor to overall health, plays a vital role in supporting such a lifestyle. Exercise induces complex molecular responses that mediate both acute metabolic stress and long-term physiological adaptations. FGF21 (fibroblast growth factor 21) and GDF15 (growth differentiation factor 15) are recognized as metabolic stress markers, while their receptors play critical roles in cellular signaling. However, the differential gene expression patterns of these molecules in trained and untrained individuals following exhaustive exercise remain poorly understood. This study aimed to examine the transcriptional and protein-level responses in trained and untrained individuals performed a treadmill maximal exercise test to voluntary exhaustion. Blood samples were collected at six time points (pre-exercise, immediately post-exercise, and 0.5 h, 6 h, 24 h, and 48 h post-exercise). Gene expression of FGF21, GDF15, FGFR1 (fibroblast growth factor receptors), FGFR3, FGFR4, KLB (β-klotho), and GFRAL (glial cell line-derived neurotrophic factor receptor alpha-like) was analyzed using RT-qPCR, while plasma protein levels of FGF21 and GDF15 were quantified via ELISA. The results obtained were statistically analyzed by using Shapiro–Wilk, Mann–Whitney U, and Wilcoxon tests in Statistica 13 software. Untrained individuals demonstrated significant post-exercise upregulation of FGFR3, FGFR4, KLB, and GFRAL. FGF21 and GDF15 protein levels were consistently lower in trained individuals (p < 0.01), with no significant correlations between gene and protein expression. Trained individuals showed more stable expression of genes, while untrained individuals exhibited transient upregulation of genes after exercise. Full article

Breathing reserve (BR) is the remaining proportion of achievable minute ventilation that remains unutilized at total exhaustion during exercise. Previous studies have found a smaller BR in endurance-trained athletes compared to untrained controls. However, most of these studies have examined men. Given that women have a greater ventilatory limitation than stature-matched men, the present cross-sectional study aimed to investigate how this sex difference influences BR and lung function tests in endurance-trained females compared to matched, untrained females. To obtain further insight, we also aimed to investigate whether VO₂max serves as a predictor of BR. We examined 15 female elite runners and 15 healthy, matched female controls aged 24–33 years with regard to pulmonary function, MVV, V_Emax, BR, and VO₂max. The elite runner group had a median BR of 5%, while that of the controls was 21%, representing a significant difference. Lung function tests showed no differences between the two groups. A moderate association was found between VO₂max and BR. The female elite runners demonstrated a lower BR than the group of matched, untrained controls, which was lower than that found for male elite athletes in previous studies. This may indicate a greater ventilatory demand in female relative to male endurance athletes. Full article

The investigation of the neuromuscular components of fatigue in team sports, especially in developmental ages, is limited. This study aimed to examine the neuromuscular fatigue and recovery patterns in prepubertal and adult female handball players, focusing on the soleus (SOL) and tibialis anterior (TA) muscles. Fifteen prepubertal (11.1 ± 0.9 years) and fourteen adult (22.0 ± 3.4 years) females performed a sustained isometric plantar flexion at 25% of maximal voluntary contraction (MVC) until exhaustion. The electromyographic (EMG) activity of the SOL and TA, torque, and central activation ratio (CAR) were recorded throughout the experiment. Endurance time was similar between groups (girls: 104 ± 93.5 s; women: 94.4 ± 30.2 s, p > 0.05), and both demonstrated progressive increases in muscle activation, without significant group differences for SOL and TA EMG (p > 0.05). Following fatigue, the torque and soleus (SOL) EMG activity decreased significantly compared to the pre-fatigue values in both groups (p < 0.001) and recovered (p > 0.05) in prepubertal and adult females within the first 3 and 6 min, respectively. The CAR remained unchanged over time, without significant differences observed between age groups (p > 0.05). These findings suggest that neuromuscular responses to fatigue are comparable between prepubertal and adult females, but recovery is significantly faster in prepubertal girls. Consequently, these findings underscore the need for age-specific recovery strategies in training programs, with tailored exercise-to-rest ratios to enhance performance and reduce fatigue during handball-specific activities. Full article

Background: Whole-body electromyostimulation (WB-EMS) combines full-body electrical muscle stimulation with instructor-assigned exercise. Electrical impulses are transmitted to the peripheral muscles through electrodes applied to the body. This study compared two training methodologies, WB-EMS training and traditional resistance training, to determine which approach leads to greater strength improvement in terms of 1-repetition maximum (1-RM). Methods: Twenty sedentary women participated in a 10 weeks protocol with five evaluations conducted every two weeks. The WB-EMS group trained for 20 min per week, and the resistance training group (RT) performed an average of two training sessions per week, lasting 60 min each. Both groups were evaluated using three exercises: back squat and hammer curl (1-RM), and plank exercise (time to exhaustion). Results: Both groups increased their performance in squat (WB-EMS +36%, p = 0.0001; RT +34%, p = 0.0001), curl (WB-EMS +42%, p = 0.0001; RT +33%, p = 0.0001), and plank (WB-EMS +103%, p = 0.0001; RT +65%, p = 0.0001). No significant time × training interaction was found for any exercise, indicating that the two groups improved similarly. Conclusions: Although WB-EMS did not confer greater strength improvement than traditional resistance training, it offers a time-efficient alternative, achieving similar results with reduced time commitment. Full article

Background/Objectives: Creatine and β-alanine are two widely used dietary supplements known to enhance exercise performance and improve body composition; however, less is known regarding the synergistic effects of combining the two supplements. Methods: A systematic search was conducted across PubMed/MEDLINE, Scopus, and Web of Science databases for randomized controlled trials (RCTs) published up to March 2025. Eligible studies included adult participants receiving creatine and β-alanine together compared to creatine or β-alanine alone for at least four weeks and assessed measures of exercise performance and/or body composition. Study quality was assessed using the Cochrane Risk of Bias tool. Results: A total of 7 randomized controlled trials (n = 263 participants; 231 males and 32 females) met the inclusion criteria. Collectively, the combination of creatine and β-alanine supplementation enhanced high-intensity exercise performance, particularly anaerobic power and repeated-bout performance, compared to creatine or β-alanine alone. Co-ingestion of creatine and β-alanine supplementation did not increase measures of maximal strength compared to creatine alone. The effects of creatine and β-alanine supplementation on body composition were equivocal, with one study reporting greater lean mass gains and fat mass reductions compared to creatine and β-alanine supplementation individually, while another found no significant improvements. Additionally, no significant improvements in aerobic endurance capacity (VO₂max, lactate threshold, or time to exhaustion) were observed from creatine and β-alanine supplementation co-ingestion. Conclusions: The combination of creatine and β-alanine supplementation may be effective for enhancing high-intensity exercise performance but has no greater effect on maximal strength, body composition, or measures of aerobic capacity compared to creatine or β-alanine alone. Full article

Background: This study aimed to investigate the acute changes in muscle and tendon viscoelastic properties in response to a progressive treadmill VO₂max test among professional male soccer players. Methods: Bilateral assessments at five sites—the Achilles tendon (AT), biceps femoris, semitendinosus, rectus femoris (RF), and sternocleidomastoid (SCM)—measured tone (oscillation frequency), dynamic stiffness, logarithmic decrement (elasticity), stress relaxation time, and creep. Each site was probed five times and values averaged. Repeated-measures ANOVA (Time × Side) with Bonferroni correction tested pre- to post-exercise changes; Pearson’s r examined associations with VO₂max. Results: Significant Time effects (all p < 0.05) were observed for RF frequency (η_p² = 0.226), RF creep (η_p² = 0.144), AT stiffness (η_p² ≈ 0.035), AT frequency (η_p² = 0.035), and SCM frequency (η_p² = 0.037). Post-exercise, right AT stiffness fell by 65 ± 14 N/m (p = 0.015), while left AT stiffness rose by 22 ± 9 N/m (p = 0.015). RF stiffness decreased by 28 ± 6 N/m (p < 0.001) and tone by 1.2 ± 0.3 Hz (p < 0.001), with creep (+0.08 ± 0.02; p < 0.001) and relaxation time (+1.5 ± 0.7 ms; p < 0.001) increasing. SCM tone declined by 0.8 ± 0.4 Hz (p = 0.010). Baseline RF properties—frequency (r = −0.597), stiffness (r = −0.59), relaxation time (r = 0.53), and creep (r = 0.48)—correlated moderately with VO₂max (all p < 0.05). Conclusions: These findings suggest that viscoelastic adaptations to exhaustive aerobic exercise are tissue- and side-specific, and that rectus femoris viscoelastic properties may serve as potential indicators of endurance readiness. Full article

Background: Quasipaa spinosa crude extract (QSce), a natural source rich in proteins such as parvalbumin (PV), has been traditionally used to promote physical recovery. However, its mechanisms in mitigating exercise-induced fatigue remain unclear. Methods: Using a murine treadmill exhaustion model, we evaluated the effects of QS-derived Parvalbumin (QsPV) (30 and 150 mg/kg/day) on endurance capacity, oxidative stress, tissue injury, and muscle function. Indicators measured included time to exhaustion, intracellular calcium levels, antioxidant enzymes [superoxide dismutase (SOD), glutathione peroxidase (GSH-Px)], lipid peroxidation (malondialdehyde, MDA), injury markers [creatine kinase (CK), lactate dehydrogenase (LDH), cardiac troponin I (cTnI)], renal function (blood urea), and muscle force. Results: QsPV-150 significantly increased time to exhaustion by 34.6% compared to the exercise-only group (p < 0.01). It reduced MDA by 41.2% in skeletal muscle and increased SOD and GSH-Px levels by 35.4% and 28.1%, respectively. Serum CK, LDH, and cTnI were reduced by 39.5%, 31.7%, and 26.8%, respectively, indicating protection against muscle and cardiac injury. QsPV also decreased blood urea by 22.3% and improved renal histology, with reduced glomerular damage and tubular lesions. At the molecular level, QsPV restored calcium balance and downregulated calpain-1/2 and atrophy-related genes (MuRF-1, MAFbx-32). Muscle contractile force (GAS and SOL) improved by 12.2–20.3%. Conclusions: QsPV attenuates exercise-induced fatigue through multi-organ protection involving calcium buffering, oxidative stress reduction, and anti-atrophy effects. These findings support its potential as a natural recovery-enhancing supplement, pending further clinical and pharmacokinetic studies. Full article

Background and Objective: Fatigue represents a hallmark symptom in Multiple Sclerosis (MS), but its diagnosis and clinical evaluation is difficult because it is described as a subjective feeling of exhausted physical and mental sensation. Studies have also shown that approaches based on assisted therapies and robotics, as well as the use of vibration, which are used to improve sensory integration, reduce fatigue. The primary outcome in this study is to evaluate the effects of the application of focal vibrations on the reduction in fatigue, muscle strength, and endurance in MS patients with moderate disability. The secondary outcome is to assess the effects on quality of life, cognitive status, and mood. Methods: We enrolled 40 MS patients. The study was designed as a parallel randomized controlled trial: 20 patients were assigned to the experimental group (EG), who received vibration training, and 20 to the control group (CG), who received traditional physical exercise. Results: We found significant differences in the EG in fatigue, motor, and cognitive outcome and improvement of some aspects of quality of life (QoL). There are correlations between perceived multidimensional fatigue and cadence, step length, and health quality of life composite. Conclusions: Our study demonstrated the potential effectiveness of vibration training in balance, walking endurance, and reduction in the risk of falls in patients with Multiple Sclerosis. In addition, we added evidence about fatigue, non-motor outcomes, in particular promoting mental and physical QoL and individual life satisfaction. The name of the registry is clinicaltrial.gov; the number of registration id NCT05783999; and the date of registration is 14 March 2023. Full article

Background: Sprinting, a high-intensity, short-duration exercise, induces oxidative stress. This causes molecular and ultrastructural alterations. Antioxidant supplementation may mitigate side effects of near or complete exhaustion. Methods: Twenty-eight healthy male adult rats received orally normal saline, carboxymethylcellulose (vehicle), artificial, N-acetylcysteine or a natural antioxidant, Rutin. Rats were subjected to treadmill sprinting at increasing speeds for 5 days/week. After 26 days, samples were collected to measure oxidative stress (malondialdehyde, MDA; the ratio of reduced-to-oxidized glutathione, GSH/GSSG), inflammation markers (enzymatic level of inducible nitric oxide synthase, iNOS; cytokine level of tumor necrosis factor alpha, TNFα) and for transmission electron microscopy (TEM) analysis. Results: Rutin attenuated MDA levels and increased antioxidant protection in all tissues, while NAC decreased the lipid peroxidation in all tissues except the lungs. NAC increased aortic inflammation, with higher TNF-α and iNOS. Sprinting caused intimal detachment in the heart and aorta. Rutin and NAC minimized endocardium alterations. Additionally, Rutin prevented myocardial disorganization. Conclusions: Rutin mitigated the oxidative stress damage of sprinting in the heart, aorta, skeletal muscle and lung. NAC protected against oxidative injury caused by sprinting in the heart, aorta and muscle but not the lung, and it induced aortic inflammation. Full article

Objectives: The purpose of this study is to quantitatively evaluate the combined effects of sports massage, blood flow restriction (BFR), and cold therapy on quadriceps recovery in mixed martial arts (MMA) athletes following eccentric exercise, focusing on muscle biomechanical properties, pain, and strength. Methods: This randomized, single-blind clinical trial involved 36 men and women MMA-trained participants, divided into three groups: massage (n = 12) received massage, BFR/cool (n = 12) received combined BFR and cooling, and control (n = 12) received passive rest as a control. The fatigue protocol involved MMA fighters performing five sets of plyometric jumps on a 50 cm box until exhaustion, with 1-min breaks between sets. After that, the massage group received a 20-min massage overall using standardized techniques; BFR/cool underwent a 20-min alternating blood flow restriction (200 mmHg) and cooling treatment with ice bags on the quadriceps; and the final group served as the control group with passive rest and no intervention. Participants were assessed four times—before exercise, immediately after exercise, 24 h post-exercise (after two recovery sessions), and 48 h post-exercise (after four recovery sessions)—for perfusion unit (PU), muscle elasticity, pressure pain threshold (PPT), reactive strength index (RSI), and total quality recovery (TQR). Results: The statistical analysis revealed significant effects of both massage and BFR/cooling interventions across key recovery outcomes, with large effect sizes for time-related changes in RSI (p < 0.0001; η² = 0.87), elasticity (p < 0.0001; η² = 0.84), and PPT (p < 0.0001; η² = 0.66). Notably, post-exercise 48 h values for RSI, elasticity, PU, and TQR were significantly improved in both the massage and BFR/cool groups compared to control (p < 0.05)), while no significant group differences were observed for PPT. Conclusions: The study concludes that both massage and combined blood flow restriction with cooling interventions significantly enhance post-exercise recovery—improving muscle perfusion, elasticity, reactive strength, and perceived recovery—compared to passive rest. Full article

Objective: This study investigated the dose–response relationship of inspiratory muscle training (IMT) on respiratory muscle strength, lactic acid accumulation and exercise tolerance in amateur runners. Methods: Thirty male amateur runners were randomly assigned to three groups: a high-intensity IMT (HIMT) group, a low-intensity IMT (LIMT) group, and a control group. In addition to their regular training regimen, the high-intensity and low-intensity IMT groups underwent a supervised IMT protocol for a duration of 8 weeks. The primary outcome measures included maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), time to exhaustion (TTE), blood lactate (BLa), rate of perceived exertion (RPE), and rate of perceived breathlessness (RPB). Secondary outcomes encompassed VO2 max, forced vital capacity (FVC), forced expiratory volume in one second (FEV₁), and the FEV₁/FVC ratio. Results: After 8 weeks of IMT, the MIP of HIMT and LIMT were significantly improved (p < 0.01), and the MEP of both groups also increased (p < 0.01). There were no significant changes in FVC and FEV₁ (p > 0.05), but only FEV₁/FVC in HIMT was significantly improved (p < 0.01). Exercise testing showed a significant increase in TTE in both the HIMT and low LIMT groups (p < 0.01). Post-exercise RPE scores were lower in both the HIMT group (p < 0.01) and LIMT group (p < 0.05), and both HIMT and LIMT groups’ post-exercise RPB scores were also reduced in both (p < 0.05). In addition, blood lactate accumulation was significantly lower in both HIMT (p < 0.01) and LIMT (p < 0.05). There were no significant changes in VO2 max (p > 0.05) and HR peak (p > 0.05). Conclusion: IMT for 8 weeks can improve respiratory muscle strength, prolong exercise time, improve blood lactate accumulation, subjective fatigue, and dyspnea during exercise. Among them, high-intensity IMT can better improve exercise tolerance. Full article

Background and Objectives: This study compared the effects of blood flow restriction resistance exercise (BFR-RE) and high-load resistance exercise (HL-RE) in voluntary exhaustion on quadriceps muscle adaptations in untrained young males. Materials and Methods: This study used a randomized controlled design that included 30 untrained young males (age = 21.42 ± 2.51). The BFR-RE group performed leg extension exercises with 60% occlusion pressure and 30% of one maximum repetition in volitional exhaustion. The same exercise was conducted at 70% 1RM in the HL-RE group. Fourteen variables were used to evaluate the intervention efficacy, including muscle thickness, stiffness, strength, cross-sectional area (CSA), and subcutaneous fat thickness. Analyses were reported using frequentist and Bayesian approaches. The Bayes factor (BF10 and BFincl) was interpreted based on negative and positive values. Results: The results revealed that the main effect of time was statistically significant for muscle strength, thickness, CSA, and stiffness (p < 0.05, BFincl > 1) and, in intragroup comparisons, both groups showed improvements in these parameters (p < 0.05, BF10 > 1). A statistically significant decrease in subcutaneous fat thickness was observed in the BFR-RE group (p < 0.05, BF10 > 1), while this change was not observed in the HL-RE group (p > 0.05, BF10 < 1). Similarly, a statistically significant increase in right rectus femoris muscle stiffness was detected in the BFR-RE group (p < 0.05, BF10 > 1) but not in the HL-RE group (p > 0.05, BF10 < 1). Furthermore, time’s main effect was statistically insignificant for thigh circumference (p > 0.05, BFincl < 1). The group × time interaction was statistically significant only for peak power leg flexion left (p < 0.05, BFincl > 1), and a statistically significant difference in favor of the BFR-RE group was observed in the intergroup comparisons (p < 0.05, BF10 > 1). Conclusions: In conclusion, BF-RE exercise with voluntary exhaustion may be as effective as HL-RE for hypertrophic adaptations in untrained young males. Full article

Objectives: This study aimed to evaluate the reliability of muscle oxygen saturation (SmO₂) and its correlation with variables from an inertial measurement unit (IMU) sensor placed on the knee at different exercise intensities. Methods: Fourteen university athletes participated in the study. Incremental ergospirometry was performed to exhaustion to calculate V’O₂max, determine training zones, heart rate, and workload using the IMU, and analyze muscle metabolism by SmO₂. Results: The analysis revealed significant differences between moderate-to-high-intensity zones (80–89% vs. 50–69%, Δ = 27% of SmO₂; p < 0.001) and high-intensity zones (90–100% vs. 50–79%, Δ = 35% of SmO₂; p < 0.001). SmO₂ values showed moderate reliability at moderate exercise intensities (e.g., ICC 0.744 at 50%) and high variability at higher intensities, with ICC values around 0.577–0.594, and CV% increasing up to 77.7% at 100% intensity, indicating decreasing consistency as exercise intensity increases. SmO₂ significantly decreases with increasing angular velocity (β = −13.9, p < 0.001), while knee joint load only shows significant correlations with SmO₂ in the moderate-to-high-intensity zones (r = 0.569, p = 0.004) and high-intensity zones (r = 0.455, p = 0.012). Conclusions: SmO₂ is a key predictor of performance during maximal incremental exercise, particularly in high-intensity zones. Moreover, SmO₂ has the potential to serve as a physiological marker of the internal load on the muscles surrounding the knee during exercise. The SmO₂ decrease could depend on the angular velocity and impact of the exposed knee during running. Full article

Objective: Prolonged microgravity environments impair skeletal muscle homeostasis by triggering fiber-type transitions and metabolic dysregulation. Although exercise and nutritional interventions may alleviate disuse atrophy, their synergistic effects under microgravity conditions remain poorly characterized. This study investigated the effects of an 8-week ketogenic diet combined with aerobic exercise in hindlimb-unloaded mice on muscle fiber remodeling and metabolic adaptation. Methods: Seven-week-old male C57BL/6J mice were randomly divided into six groups: normal diet control (NC), normal diet with hindlimb unloading (NH), normal diet with hindlimb unloading and exercise (NHE), ketogenic diet control (KC), ketogenic diet with hindlimb unloading (KH), and ketogenic diet with hindlimb unloading and exercise (KHE). During the last two weeks of intervention, hindlimb unloading was applied to simulate microgravity. Aerobic exercise groups performed moderate-intensity treadmill running (12 m/min, 60 min/day, and 6 days/week) for 8 weeks. Body weight, blood ketone, and glucose levels were measured weekly. Post-intervention assessments included the respiratory exchange ratio (RER), exhaustive exercise performance tests, and biochemical analyses of blood metabolic parameters. The skeletal muscle fiber-type composition was evaluated via immunofluorescence staining, lipid deposition was assessed using Oil Red O staining, glycogen content was analyzed by Periodic Acid–Schiff (PAS) staining, and gene expression was quantified using quantitative real-time PCR (RT-qPCR). Results: Hindlimb unloading significantly decreased body weight, induced muscle atrophy, and reduced exercise endurance in mice. However, the combination of KD and aerobic exercise significantly attenuated these adverse effects, as evidenced by increased proportions of oxidative muscle fibers (MyHC-I) and decreased proportions of glycolytic fibers (MyHC-IIb). Additionally, this combined intervention upregulated the expression of lipid metabolism-associated genes, including CPT-1b, HADH, PGC-1α, and FGF21, enhancing lipid metabolism and ketone utilization. These metabolic adaptations corresponded with improved exercise performance, demonstrated by the increased time to exhaustion in the KHE group compared to other hindlimb unloading groups. Conclusions: The combination of a ketogenic diet and aerobic exercise effectively ameliorates simulated microgravity-induced skeletal muscle atrophy and endurance impairment, primarily by promoting a fiber-type transition from MyHC-IIb to MyHC-I and enhancing lipid metabolism gene expression (CPT-1b, HADH, and PGC-1α). These findings underscore the potential therapeutic value of combined dietary and exercise interventions for mitigating muscle atrophy under simulated microgravity conditions. Full article