Search Results (2,225)

Muscle vulnerability occurs at both extremes of the human lifespan, although its biological significance differs substantially between developmental growth and late-life decline. During childhood and adolescence, insufficient muscle accretion reflects disruption of physiological anabolic trajectories driven by inadequate energy availability, inflammatory burden, endocrine imbalance, or disease-associated catabolism. In older adults, muscle deterioration is characterized by anabolic resistance, neuromuscular remodeling, chronic low-grade inflammation, and hormonal decline, culminating in sarcopenia and loss of functional independence. The absence of harmonized diagnostic frameworks across age groups limits direct translational extrapolation. A lifespan-informed perspective distinguishing growth-supportive from function-preserving nutritional approaches is, therefore, required. This narrative review examines how major classes of nutritional bioactive interact with molecular pathways regulating skeletal muscle homeostasis in fragile populations across the lifespan. The analysis encompasses energy adequacy, protein quantity and quality, amino acid-dependent anabolic signaling, vitamin D status, lipid-derived mediators, redox-modulating phytochemicals, and micronutrients supporting mitochondrial bioenergetics. In pediatric contexts, nutritional interventions primarily aim to restore anabolic permissiveness within a structurally intact growth environment. In aging individuals, strategies focus on mitigating anabolic resistance through optimized protein intake, correction of micronutrient insufficiencies, and integration with resistance exercise to preserve functional capacity. This narrative review emphasizes the need to distinguish mechanistic rationale from clinically validated interventions, as improvements in molecular pathways do not consistently translate into meaningful functional outcomes. Full article

Sarcopenia is increasingly recognized as a key extracardiac manifestation of heart failure (HF), contributing to functional impairment, reduced quality of life, and adverse clinical outcomes. Characterized by progressive loss of skeletal muscle mass, strength, and physical performance, it affects more than half of hospitalized HF patients. It is independently associated with increased mortality and reduced exercise capacity. The pathophysiology of sarcopenia in HF is multifactorial and closely linked to metabolic and nutritional disturbances. Chronic inflammation, neurohormonal activation, oxidative stress, endothelial dysfunction, and anabolic resistance contribute to muscle catabolism and impaired protein synthesis. These alterations are further exacerbated by inadequate dietary protein intake and micronutrient deficiencies, promoting progressive muscle wasting and functional decline. Sarcopenia may also represent an early and potentially modifiable stage in the continuum toward cardiac cachexia. This narrative review provides a comprehensive synthesis of current evidence on the epidemiology, pathophysiological mechanisms, and management of sarcopenia in HF, with particular emphasis on nutritional and metabolic determinants. Emerging data support a multimodal therapeutic approach integrating exercise training with targeted nutritional strategies, including adequate protein intake, essential amino acid supplementation, and correction of micronutrient deficiencies. However, evidence from large, well-designed trials remains limited. In summary, improved recognition and integrated management of sarcopenia in HF are essential. Future research should focus on the development of effective, nutrition-centered therapeutic strategies. Full article

Background: This study aimed to investigate the extent and time course of peripheral neuromuscular fatigue of the knee extensors following different concurrent training protocols in recreationally active men. Methods: In a randomized, counterbalanced, crossover design, ten participants completed one exercise session of three concurrent exercise protocols in consecutive weeks and in similar resting conditions: traditional concurrent training (TCT), sprint interval training (SIT), and high-intensity resistance circuit training (HRC). Maximal voluntary isometric contraction (MVIC) and electrically evoked tetanic force of the knee extensors were assessed before, immediately after, and at 24 and 48 h following each exercise session. Linear mixed models were used to examine the differences among exercise modalities and time points. Results: No significant changes were found in MVIC force following HRC and TCT at any time point (p > 0.05), while significant declines were observed post-exercise (p = 0.015), 24 h (p = 0.001) and at 48 h (p = 0.003) after SIT. Moreover, MVIC force was significantly lower for SIT than HRC at 48 h (p = 0.001). Tetanic force significantly declined in SIT from pre-exercise to post-exercise (p = 0.034), with significant differences when compared to HRC (p = 0.003) and TCT (p = 0.003). HRC and TCT induced no knee extensor fatigue, contrary to a single session of SIT. Conclusions: Peripheral fatigue seemed to prevail following SIT in comparison with HRC and TCT, as seen by the decreased tetanic force in the former only. From an applied perspective, practitioners should carefully plan training activities to be performed the days following a SIT session, as force-generating capacity may be impaired for up to 48 h. Full article

Background/Objectives: Understanding the available interventions and circumstances under which physical therapy is administered to patients with diabetic foot ulcers is important to provide more evidence regarding physical therapy and associated outcomes in this population. This study aimed to investigate the scope, nature, and extent of literature on physical therapy interventions for adults with diabetic foot ulcers. Methods: Articles on physiotherapy interventions for adults with diabetic foot ulcers published up to 30 June 2024 were included. Relevant articles were identified through searches of PubMed, Scopus, MEDLINE, and the Cochrane Library databases. Opinion articles, study protocols, meeting abstracts, and articles that did not describe physical therapy interventions were excluded. Results: The systematic search identified 13 articles that met the inclusion criteria. Eleven of the 13 articles were specifically related to outpatient physical therapy. Outpatient physiotherapy included unloading gait instruction, ankle stretching instruction, progressive resistance training, and aerobic exercise. In two other cases, exercise instructions were practiced in the early postoperative period of the wound during the hospitalization period. A multidisciplinary approach aimed at improving postoperative activities of daily living was included. The main efficacy indices were the wound reduction rate, plantar pressure reduction, hemodynamics, ankle joint range of motion, walking ability, and other physical function-related parameters. Conclusions: Physiotherapy during outpatient follow-up may contribute to preventing wound deterioration and maintaining physical function in patients with stable DFUs. However, standardized protocols regarding intervention timing, exercise intensity, and wound severity remain unestablished, and interventions should be applied cautiously based on individual clinical conditions. Full article

Background/Objectives: Aging is closely associated with sarcopenia, which has a significant impact on muscle mass and its function. Protein supplementation (PS) brings benefits such as lean mass and strength gains during exercise training. This paper determined the optimal regimen among the composites of variate protein sources and training modalities for older individuals. Methods: We comprehensively searched the electronic databases, namely MEDLINE Complete, PEDro, the Cochrane Library, Google Scholar, EMBASE, and the China National Knowledge Infrastructure, from its inception until December 2025. We included randomized controlled trials (RCTs) that examined the effectiveness of any type of PS combined with one of three exercise types—resistance, aerobic, or multicomponent training—in untrained older adults. The main outcomes used to identify sarcopenia were assessed, including lean mass, handgrip and leg strength, and physical mobility measures. Network meta-analysis (NMA) was performed by a frequentist method using random-effects models. The estimated treatment effect was expressed as the standard mean difference (SMD) with a 95% confidence interval (CI). Any potential factor moderating the treatment effect was determined by the meta-regression analyses, including participant characteristics and methodological factors. Certainty of evidence (CoE) was assessed by the GRADE framework. Results: In total, we included 235 RCTs (20,980 participants) for analyses. A total of 10 protein sources (whey, soy, casein, milk, and the others) were identified, corresponding to 24 monotherapy and combined regimens of PS and exercise. Among the treatment arms, whey plus resistance training was ranked as the most effective treatment for muscle mass (large SMD, 1.29; CoE, moderate) and leg strength (large SMD, 1.16; CoE, moderate); additionally, whey plus multicomponent exercise training achieved the most promising effects on such sarcopenia-related physical indicators such as chair rise (large effect, SMD = 1.09; CoE: high), timed up and go (medium SMD, 0.70; CoE, high), and global mobility score (large SMD, 1.02; CoE, high). Conclusions: The treatment efficacy appears to be moderated by the participant’s conditions, PS resource, and PS dose, particularly the outcome of muscle mass and strength. The present NMA results indicate that whey protein incorporated with resistance training is the optimal program to help combat sarcopenia in older adults. Full article

Objective: The goal was to investigate the relationship between methodological adherence and clinical outcomes in Progressive Resistance Training (PRT) for Parkinson’s Disease (PD), specifically identifying why findings of “superiority” over active controls remain inconsistent. Methods: This umbrella review utilized a multi-stage process to identify a sample of the primary literature for methodological analysis. An initial search identified 38 systematic reviews published within the specified timeframe. From the reference lists of these reviews, a subset of 34 primary clinical studies was purposefully selected. Inclusion was prioritized for studies providing comprehensive methodological data on PRT protocols and standardized clinical outcomes. Interventions were evaluated using a three-tiered framework: (1) training protocol with specifications of Frequency, Intensity, Time, Type, Volume, and Progression (FITT-VP) (General Exercise), (2) FITT-VP integrated with the American College of Sports Medicine (ACSM) Supplementary Guidelines (Integrated Guidelines), and (3) principles of progression (mechanistic growth). Studies were categorized by control type (active (e.g., aerobic or balance), n = 26; passive (e.g., standard care or no exercise), n = 8). Results: In trials that compared PRT with an active control group, PRT achieved clinical superiority in 57% (n = 15) of trials and 46% (n = 12) when focusing on trials with an effect on specific functional or balance outcomes. Among these successful interventions, 75% maintained high adherence (≥70%) to the Integrated Guidelines, and 58% maintained high adherence to the principles of progression. In the 53% (n = 14) of studies where PRT was found non-superior (equivalent or inferior in functional or balance outcomes) to an active control, 0% met the high adherence threshold for progression. While general FITT-VP compliance remained high (78%), the failure to implement systematic load, specificity, and variation served as a definitive barrier to competitive superiority. In the 100% of studies where PRT outperformed passive controls, high progression was present in 57% of cases. This may suggest that while a baseline resistance stimulus outperforms inactivity, it is fundamentally insufficient to outperform other active clinical therapies. Conclusions: This umbrella review indicates that adherence to the principles of progression may be an important factor influencing the clinical outcomes of PRT in individuals with PD. The variability observed in the current literature suggests that inconsistent application of established exercise frameworks—rather than the failure of the modality itself—could be a contributing element to the reported “inconclusiveness.” To potentially enhance functional outcomes and the comparative effectiveness of PRT, future research should consider prioritizing structured adherence to FITT-VP, Integrated Guidelines, and progression-based frameworks. Establishing a 70% adherence threshold is proposed as a potential benchmark to improve protocol consistency and support rehabilitation efficacy in this population. Full article

Background: Blood flow restriction training (BFRT) is a low-load resistance training modality capable of inducing muscle hypertrophy and strength adaptations that are comparable to traditional high-load resistance training. Beyond athletic performance settings, BFRT has growing relevance for musculoskeletal health, rehabilitation and populations unable to tolerate high mechanical loads. However, substantial inter-individual variability in adaptive responses has been reported. Genetic and molecular factors may partly contribute to this variability and inform more individualised exercise strategies. Other intrinsic and extrinsic factors, including age, sex, training status, nutrition, and protocol-related differences, may also influence adaptive responses. Objective: This scoping review aimed to map available evidence on molecular modulators of adaptation to BFRT and to identify gaps in the literature regarding genetic influences on BFRT responses. Methods: A structured search of PubMed, Web of Science and Google Scholar was conducted till 1 February 2026. Experimental and quasi-experimental studies examining BFRT in relation to genetic polymorphisms, gene expression, and molecular signalling pathways associated with strength and hypertrophy outcomes were included. Primary outcomes were genetic and molecular factors relevant to BFRT adaptation, including genetic polymorphisms, gene expression, and molecular signalling markers. Secondary outcomes included muscle strength, hypertrophy, vascular responses, and related functional outcomes where reported. Study selection and data extraction were conducted according to PRISMA-ScR guidelines. The methodological quality of randomised controlled trials was assessed using the PEDro scale. This scoping review was registered retrospectively in the Open Science Framework on 17 March 2026, after completion of the literature search. Results: From an initial 47 records, only three studies (n = 3) met the inclusion criteria. The included studies reported molecular responses associated with BFRT, including downregulation of proteolytic genes, suppression of myostatin expression, and upregulation of angiogenic markers. Notably, no studies directly examined genetic polymorphism or genotype–BFRT interactions, highlighting a clear need for these studies in this field. Conclusions: This scoping review therefore identifies a critical evidence gap, with genotype-informed BFRT prescription remaining unsupported by the current literature. Limited evidence supports the possible role of BFRT in molecular responses associated with muscle adaptation. Future research should prioritise well-designed studies integrating both genetic and molecular analyses to better understand inter-individual variability in BFRT adaptations. Full article

Background: Blood flow restriction (BFR) resistance exercise has emerged as a training methodology capable of inducing muscular adaptations comparable to traditional high-load training despite substantially lower mechanical loads. While low-load BFR protocols (20–50% 1RM) are well-established, emerging evidence supports applications across the full loading spectrum, including moderate-to-high loads (>50–90% 1RM), contralateral training effects, and proximal–distal adaptations. In this second installment of the Blood Flow Restriction in Athletic Populations series, we review current evidence on BFR resistance exercise in athletic populations, with emphasis on morphological, neuromuscular, and functional adaptations across diverse application contexts. Methods: A narrative review of research examining BFR resistance exercise in trained and athletic populations was conducted via a PubMed/MEDLINE search. Search terms: (“blood flow restriction” OR “BFR” OR “occlusion training” OR “KAATSU”) AND (“resistance training” OR “resistance exercise” OR “strength training”) AND (“athletes” OR “athletic” OR “trained” OR “elite” OR “sport”) AND (“cross-education” OR “contralateral” OR “cross transfer” OR “proximal” OR “distal”). Studies investigating low-load (20–50% 1RM) and moderate-to-high load (>50% 1RM) protocols, contralateral cross-education effects, and proximal–distal adaptations were evaluated. Primary outcomes included muscle hypertrophy, strength, power, and sport-specific performance measures. Results: Low-load BFR resistance exercise has been shown to produce significant improvements in muscle hypertrophy and strength gains over 4–12 week interventions compared to low-load control conditions. Moderate-to-high load BFR enhanced barbell velocity and power output, particularly at loads > 80% 1RM with intermittent inflation protocols. Contralateral and cross-transfer effects of BFR training demonstrate variable efficacy across muscle groups, with the most consistent evidence supporting cross-transfer enhancement of training adaptations when BFR is applied to one body region while exercising another. Proximal BFR application induced adaptations in both proximal and distal musculature, suggesting systemic mechanisms beyond local vascular restriction. Conclusions: BFR resistance exercise represents a versatile training modality producing meaningful morphological and neuromuscular adaptations across the loading spectrum. Contralateral and proximal–distal effects expand practical applications for injury rehabilitation and targeted adaptation. These findings support BFR integration within periodized training programs when mechanical load management is prioritized. Full article

Background: Blood flow restriction (BFR) training induces morphological and neuromuscular adaptations using low-intensity exercise (20–40% 1RM), offering a reduced mechanical load alternative to traditional high-load resistance training. Safe and effective implementation, however, requires a clear understanding of physiological mechanisms, contraindications, and pressure determination methodologies. In this three-part series, we provide a comprehensive review of BFR for athletic populations and provide strength and conditioning coaches with a structured framework for screening, safety, and methodological considerations to support BFR integration in high-performance settings. Methods: A narrative review of the literature examining BFR safety, contraindication screening, adverse event reporting, and occlusion pressure determination was conducted using a PubMed and MEDLINE search. Search terms included combinations of (“blood flow restriction” OR “BFR” OR “occlusion training” OR “KAATSU”) AND (“safety” OR “contraindications” OR “risk stratification”) AND (“arterial occlusion pressure” OR “limb occlusion pressure” OR “occlusion pressure” OR “Doppler” OR “handheld Doppler” OR “pulse oximetry” OR “cuff width” OR “capillary refill time” OR “monitoring”). Studies examining contraindication screening systems, arterial occlusion pressure calculation methods, and real-time monitoring protocols were evaluated. Primary considerations included risk stratification frameworks, pressure determination accuracy, and control parameter validation for ensuring vascular safety during application. Results: Risk stratification systems can effectively identify absolute and relative contraindications requiring medical clearance prior to BFR use. Epidemiological data indicate that adverse events are transient and non-serious, while serious events appear rare when evidence-informed protocols are applied. Doppler-based assessment remains a criterion approach for determining inflation pressure, although validated estimation methods using limb circumference and systolic blood pressure offer a pragmatic and comparable alternative for applied environments. Inflation pressures of 50–80% arterial occlusion, adjusted for cuff width, produce effective and safe stimulus. Real-time monitoring through capillary refill time, pulse strength palpation, and skin coloration can support iterative pressure optimization and help identify excessive restriction pressures. Conclusions: BFR implementation in athletic populations requires systematic screening protocols, individualized inflation pressure determination using validated methods, and real-time monitoring parameters. These foundations provide the essential safety infrastructure required before progressing to specific training applications across resistance, cardiovascular, and other performance and rehabilitation modalities. Full article

Epidemiological and clinical research on neurodegenerative diseases has shown that metabolic dysregulations increase the risk of developing Alzheimer’s Disease (AD). Many metabolic changes can be grouped into metabolic syndrome (MetS), which is defined as the presence of three or more risk factors, including insulin resistance, hyperglycemia, hypertension, central obesity, and dyslipidemia. These changes cause systemic effects that are crucial in triggering neuroinflammation and neurodegeneration, key factors in AD development. All these factors impair energy metabolism in peripheral tissues and the brain by decreasing glucose utilization, leading to alterations in O-GlcNAcylation, glycosylation, mitochondrial function, oxidative stress, chronic inflammation, synaptic dysfunction, autophagy impairment, and blood–brain barrier (BBB) dysfunction. However, these factors are modified and largely influenced by lifestyle choices. A newer perspective emphasizes that regular exercise is vital for maintaining brain metabolism as we age. Current evidence suggests that engaging in physical activity for individuals with metabolic syndrome reduces their risk of Alzheimer’s disease, enhances prognosis, and improves cognitive abilities. This review explores how metabolic syndrome relates to Alzheimer’s and highlights possible strategies for prevention and treatment. Full article

Introduction: Breast cancer-related lymphedema (BCRL) affects quality of life (QoL) and increases healthcare costs. Resistance training (RT) is proposed as a preventive strategy, although its safety and effectiveness remain uncertain. Objective: To evaluate the effectiveness and safety of RT in preventing BCRL in women at risk. Methods: MEDLINE, Embase, CENTRAL, PEDro, and LILACS databases were searched from their inception to January 2025, along with the gray literature, trial registries, and preprints. Risk of bias was assessed using RoB 2, and certainty of the evidence (CoE) was assessed using GRADE. Primary outcomes were the occurrence of lymphedema and overall QoL; secondary outcomes included pain, upper limb function, range of motion (ROM), grip strength, and adverse events. Results: Eight RCTs (n = 1131) were included. The effects of RT on lymphedema and arm volume are very uncertain (very low CoE). For QoL, pain, ROM, and grip strength, the findings were inconsistent and uncertain (low to very low CoE). Adverse events were mild and transient, with no serious complications. Conclusion: RT is probably safe in women at risk of developing BCRL. Its preventive effectiveness is highly uncertain. Well-designed RCTs with standardized diagnostic criteria, patient-centered outcomes, and long-term follow-up are needed to establish their role in BCRL prevention with greater certainty. Ethics and dissemination: This study did not require ethical approval. The results will be disseminated through publications in peer-reviewed journals and academic presentations. Registration: PROSPERO (CRD42023455720). Full article

Background: Metabolic syndrome (MetS) is a cluster of pathologies (obesity, dyslipidemia, insulin resistance, hypertension) that affects over one quarter of old adults. MetS is a condition that markedly increases the susceptibility of various organs to dysfunctionality and is associated with the development of oxidative stress. The existing guidelines point out that exercise is highly advantageous for patients with MetS. However, there is a need for specific guidance and clinical evidence. Objective: This study aimed to investigate the effects of a moderate aerobic exercise program on older women without and with MetS. Methods: A total of 120 women aged 60–70 years old were recruited and divided into two groups: healthy old women (HOW, N = 60) and old women with MetS (OW-MetS, N = 60). Anthropometric values, biochemical parameters and markers of oxidative damage were evaluated before and after moderate aerobic exercise. Exercise was performed five days per week for three months (64 sessions). Each exercise session consisted of 40 min and included the following: (a) five minutes of warm-up exercise; (b) ten minutes of flexibility exercise with resistance using own weight and coordination; (c) twenty minutes of moderate-intensity aerobic exercise (heart rate max between 60% and 70%); and (d) five minutes to cool down/stretching with respiratory techniques. Results: A significant decrease in anthropometric variables was generated by the exercise program [waist circumference 4.35 cm (p < 0.05) in OW-MetS, body fat −1.55, −1.39% (p < 0.05) and muscle mass 0.8, 1.1% (p < 0.05) in HOW and OW-MetS, respectively]. The exercise program resulted in beneficial changes in all biochemical parameters in both groups. Importantly, HOMA values showed a significant decline of −0.85 and −6.17 in HOW and OW-MetS, respectively. Furthermore, oxidative stress was present in the OW-MetS group, which was reduced by the exercise program, resulting in a decrease in protein damage [formazan 45% and 42% in HOW and OW-MetS respectively] and an increase in antioxidant defenses (thiol groups 36%, 99% and GPx 55%, 20% in HOW and OW-MetS, respectively). Conclusions: The data of this study show that moderate aerobic exercise may be potentially useful in treating and preventing MetS in older patients. Full article

Background: The purpose of this study was to compare the effects of two months of exergaming, conventional resistance exercise training, and no exercise on body composition and cardiometabolic risk factors in physically inactive older adults. Methods: For the preliminary study, twenty-four physically inactive adults aged 60–74 yrs. were allocated to an active video game training group (AVG n = 8), a conventional exercise group (CEG n = 7), or a non-exercising control group (CON n = 9). The AVG and CEG completed 24 supervised exercise training sessions over two months (three sessions per week) at self-selected, predominantly moderate-to-vigorous intensity, while the CON maintained usual daily activities. Body weight, skeletal muscle mass, body fat percentage, phase angle, and fasting blood biomarkers (glucose, total cholesterol, LDL, HDL, VLDL, and triglycerides) were assessed before and after the intervention. Results: No significant interactions were observed for body composition variables. Body weight decreased significantly following exercise training in both the AVG and CEG (p < 0.05). Significant interactions were found for total cholesterol (p = 0.001) and LDL cholesterol (p = 0.009). The AVG demonstrated significant reductions in fasting glucose, total cholesterol, and LDL cholesterol (p < 0.05), whereas the CEG showed a significant reduction only in total cholesterol. In contrast, the CON exhibited a significant increase in total cholesterol over the same period (p < 0.05). Conclusions: Two months of exergaming-based exercise training may lead to greater improvements in lipid-related cardiometabolic risk factors compared with conventional resistance exercise training in physically inactive older adults. These findings suggest that exergaming could be a promising exercise modality for supporting cardiometabolic health in aging populations. Full article

Biological differences between sexes—particularly due to fluctuating levels of 17β-estradiol and menstrual cycle dynamics—may influence exercise-induced reactive oxygen species (ROS) formation, inflammation and exercise performance. Despite these considerations, there is a lack of research exploring how estradiol and menstrual cycle phases may impact exercise performance, exercise-induced ROS formation and inflammation. This study aimed to examine whether estradiol concentration or menstrual cycle phase may be significantly associated with resistance circuit high-intensity interval training (HIIT) performance, as well as exercise-induced formation of ROS and Interleukin-6 (IL-6). A total of 30 young healthy female participants completed a single bout of resistance-based HIIT in a fasted state. Blood samples were collected at four time points: at baseline after overnight fasting, two hours after consumption of 0.5 L of water (pre-HIIT), immediately post exercise (post-HIIT) and after 15 min of recovery (15-post-HIIT). Additionally, participants attended six fasting baseline assessments scheduled across various menstrual cycle days. These sessions enabled the assessment of estradiol, ROS and IL-6 concentrations throughout the menstrual cycle without being confounded by nutritional factors. Neither baseline levels of ROS nor IL-6 differed significantly between menstrual cycle phases (luteal vs. follicular ROS: 0.013 µmol/min, p = 0.716; IL-6: 0.052, p = 0.679) menstruation status (yes vs. no ROS: −0.056 µmol/min, p = 0.259; IL-6: −0.302 pg/mL, p = 0.088) or 17β-estradiol concentrations (low (11–≤72.5 pg/mL) vs. high (>72.5–394 pg/mL) ROS: −0.038 µmol/min, p = 0.266; IL-6: +0.015 pg/mL, p = 0.906). On the resistance-circuit-HIIT intervention day, no significant differences in ROS or IL-6 were observed between estradiol concentrations (ROS: p = 0.477; IL-6: p = 0.249), menstrual cycle phase (ROS; p = 0.752; IL-6: p = 0.557) or menstruation status (ROS: p = 0.383; IL-6: p = 0.808) from baseline to pre-HIIT, post-HIIT or 15-post-HIIT. These findings should be interpreted with caution, as the menstrual cycle phases were assigned using a calendar-based approach without biochemical ovulation confirmation and the subgroup sizes were relatively small. These findings suggest that natural 17-beta-Estradiol fluctuations within the menstrual cycle, as well as differences in the menstrual cycle itself, may not substantially modulate ROS or IL-6 responses to acute resistance-based HIIT in young healthy female adults. Full article

Background: Myasthenia gravis (MG) is a chronic autoimmune disorder characterized by fluctuating skeletal muscle weakness and fatigue, leading to reduced functional independence and impaired quality of life (QoL). Although exercise has historically been discouraged due to concerns about symptom exacerbation, emerging evidence suggest that structured exercise programs may be safe and beneficial in clinically stable patients. This systematic review critically evaluates current evidence on exercise and physical activity interventions in MG, focusing on effectiveness, safety, and impact on functional outcomes, fatigue, and QoL. Materials and Methods: A systematic review was conducted following PRISMA guidelines. Searches were performed in PubMed, Web of Science, Google Scholar, Scopus and ScienceDirect for studies published between 2015 and 2025. Keywords included MG, physical activity, aerobic training, resistance training, and respiratory muscle training. Methodological quality was assessed using the Downs and Black checklist. Results: Eight controlled studies met the inclusion criteria, encompassing aerobic, resistance, combined, and respiratory muscle training interventions. Sample sizes ranged from small pilot studies to moderate-size randomized controlled trials. Overall, exercise interventions were well tolerated, with no evidence of sustained symptoms exacerbation. Aerobic and combined programs consistently improved functional capacity, muscle strength, and activities of daily living. Respiratory muscle training demonstrated improvements in pulmonary function and inspiratory muscle strength, although findings were more heterogeneous. Study quality ranged from poor to excellent, with common limitations including small sample size, short follow-up duration, and heterogeneity in exercise programs. Conclusions: Current evidence supports the safety and potential efficacy of individualized, symptom-guided exercise interventions in clinically stable MG. Regular physical activity exercise may reduce secondary deconditioning, improve functional outcomes, and enhance QoL. However, larger, high-quality randomized controlled trials with standardized programs and longer follow-up periods are required to strengthen clinical recommendations and clarify long-term effects. Full article