Search Results (473)

The paper presents an innovative theoretical concept of a bio-inspired soft gripper system with two parallel jaws, a fixed and a mobile one. It is conceived for gripping fragile or soft objects with complex, irregular shapes that are easily deformable. This novel gripper is designed for handling small objects of masses up to 0.5 kg. The maximum gripping stroke of the mobile jaw is 13.5 mm. The driving motor is a pneumatic muscle, an actuator with inherently compliant, spring-like behavior. Compliance is the feature responsible for the soft character of the gripper system, ensuring its passive adaptability to the nature of the object to be gripped. The paper presents the structural, kinematic, static, and dynamic models of the novel gripper system and describes the compliant behavior of the entire assembly. The results of the dynamic simulation of the gripper have confirmed the attaining of the imposed motion-related performance. Full article

Skeletal muscle, constituting 40–50% of total body mass, is vital for mobility, posture, and systemic homeostasis. Muscle contraction heavily relies on ATP, primarily generated by mitochondrial oxidative phosphorylation. Mitochondria play a key role in decoding intracellular calcium signals. The endocannabinoid system (ECS), including CB₁ receptors (CB₁Rs), broadly influences physiological processes and, in muscles, regulates functions like energy metabolism, development, and repair. While plasma membrane CB₁Rs (pCB₁Rs) are well-established, a distinct mitochondrial CB₁R (mtCB₁R) population also exists in muscles, influencing mitochondrial oxidative activity and quality control. We investigated the role of mtCB₁Rs in skeletal muscle physiology using a novel systemic mitochondrial CB₁ deletion murine model. Our in vivo studies showed no changes in motor function, coordination, or grip strength in mtCB₁ knockout mice. However, in vitro force measurements revealed significantly reduced specific force in both fast-twitch (EDL) and slow-twitch (SOL) muscles following mtCB₁R ablation. Interestingly, knockout EDL muscles exhibited hypertrophy, suggesting a compensatory response to reduced force quality. Electron microscopy revealed significant mitochondrial morphological abnormalities, including enlargement and irregular shapes, correlating with these functional deficits. High-resolution respirometry further demonstrated impaired mitochondrial respiration, with reduced oxidative phosphorylation and electron transport system capacities in knockout mitochondria. Crucially, mitochondrial membrane potential dissipated faster in mtCB₁ knockout muscle fibers, whilst mitochondrial calcium levels were higher at rest. These findings collectively establish that mtCB₁Rs are critical for maintaining mitochondrial health and function, directly impacting muscle energy production and contractile performance. Our results provide new insights into ECS-mediated regulation of skeletal muscle function and open therapeutic opportunities for muscle disorders and aging. Full article

Background: Muscle health is an emerging concept linked to physical performance and functional independence. However, the term lacks a standardized definition and is often used as a broad muscle-related outcome descriptor. Clinical communication and research would benefit from a conceptual model of muscle health grounded in an established framework. Methods: We conducted systematic search and narrative synthesis to identify multifactorial measurement approaches explicitly described under ‘muscle health’. PubMed and CINAHL were searched for clinical and randomized controlled trials published in the past 5 years (final search: March 2025) that used the term “muscle health.” Studies were reviewed for explicit definitions of “muscle health,” and all identified outcomes (e.g., strength, mass) and measurement tools (e.g., grip strength, ultrasound) were synthesized. This review was retrospectively registered (INPLASY202580069). Results: Of the 65 clinical or randomized controlled trials that met inclusion criteria, 29 provided an operational definition of ‘muscle health’, while 36 inferred measurements without a clear definition. The identified measurements spanned four primary categories, with body composition/muscle mass being the most common (92.3%), followed by muscle performance (78.5%), physical function (63.1%), and tissue composition (30.8%). Most studies included more than one muscle health metric (93.9%). Common assessment methods included DXA (44.6%), grip strength (64.6%), and gait speed (27.7%). Conclusions: While there are common measurement approaches, the definition of muscle health varies widely in the cited works. The framework of the International Classification of Functioning, Disability and Health, was used to identify domains aligned with muscle health components of muscle morphology/morphometry (e.g., mass and composition), functional status (performance-based tasks), and physical capacity (muscle performance). This framework provides a structured basis for evaluating muscle health in research and clinical practice. Consistent use of these domains could enhance assessment and support efforts to standardize testing and interpretation across settings. Full article

Background/Objectives: Children with DS are at an increased risk of obesity and impaired motor performance. This study aimed to compare body composition and motor performance in children with DS and typically developing (TD) peers and to explore associations between adiposity and motor function. Methods: A cross-sectional study was conducted with 42 children aged 6–12 years (23 DS, 19 TD). Body composition was assessed using bioelectrical impedance analysis. Postural stability was evaluated with the Pediatric Balance Scale; hand grip strength with hand dynamometry; physical activity with the PAQ-C; and aerobic endurance with the YMCA 3 min step test. Results: Children with DS exhibited significantly higher adiposity and lower motor performance than their TD peers. In the DS group, body fat mass was negatively correlated with physical activity (r = –0.499, p = 0.018), balance (r = –0.684, p < 0.001), and aerobic endurance (r = –0.389, p < 0.073). Regression analysis identified physical activity and fitness level as significant predictors of BMI in children with DS (R² = 0.825). Conclusions: Children with DS exhibit higher adiposity and inferior motor performance compared to their TD peers, with strong associations between adiposity and reduced physical activity, balance, and aerobic endurance. These findings underscore the importance of early targeted interventions to improve health outcomes in children with DS, particularly in regions like Saudi Arabia, where prevalence is high. Full article

Background: Basketball is a high-intensity, multidirectional sport involving frequent jumping, sprinting, and rapid changes of direction, which may expose the musculoskeletal system to varying and potentially asymmetric mechanical demands. The mechanical loading associated with basketball-specific movements may also serve as a consistent osteogenic stimulus, potentially leading to side-specific adaptations in body composition and bone characteristics. Long-term participation in basketball may lead to functional and structural asymmetries between the lower and upper limbs, potentially increasing the risk of injury and impacting performance. This study aimed to investigate structural and functional asymmetries in male basketball players using body composition, health, and performance-related measures. Methods: Thirty-eight right-handed basketball players (age: 21.1 ± 2.8 years; body mass: 86.2 ± 9.2 kg; height: 1.91 ± 8.3 cm) were assessed in a single testing session. The evaluation included bioelectrical impedance analysis (BIA), dual-energy X-ray absorptiometry (DXA), single-leg countermovement rebound jumps (CMRJs), and handgrip strength testing. Results: Significant interlimb differences were observed in lean mass and the phase angle for both the arms and legs. Performance differences favored the left leg in terms of maximum jump height (12.0 ± 17.5%, p = 0.001) and reactive strength index (RSI), whereas the right arm exhibited greater grip strength than the left (6.4 ± 5.9%, p = 0.001). DXA analysis revealed significant asymmetries in bone parameters, including bone mineral density (BMD) of the trochanter (1.81 ± 5.51%, p = 0.031, dz = 0.37), total hip (1.41 ± 4.11%, p = 0.033, dz = 0.36), and total arms (–1.21 ± 2.71%, p = 0.010, dz = 0.43), as well as bone mineral content (BMC) in total arms (–2.16 ± 5.09%, p = 0.012) and total legs (1.71 ± 3.36%, p = 0.002, 0.54). Conclusions: These findings suggest that basketball may induce both functional and structural adaptations, likely due to repetitive unilateral loading and sport-specific movement patterns. However, individual variability and the use of diverse assessment methods may complicate the detection and interpretation of asymmetries. Coaches and practitioners should monitor and address such asymmetries to reduce injury risk and optimize performance. Full article

Background: Sustainable, dual-action ergogenic strategies are underexplored; most products target a single pathway and rarely upcycle seafood sidestreams. We therefore tested an upcycled formulation combining grouper bone hydrolysate and Undaria pinnatifida extract (GU) for ergogenic and microbiota effects in mice. We tested the ergogenic and microbiota modulating effects of GU in mice versus a vehicle and a BCAA control. Methods: GU was prepared via enzymatic hydrolysis of marine by-products and administered to male ICR mice for 4 weeks. Mice were divided into five groups (n = 7/group), receiving a vehicle control, a branched-chain amino acid (BCAA) supplement, or GU at three dose levels (1X, 2X, 3X) based on human-equivalent conversion. Exercise performance was assessed via grip strength and treadmill tests. Biochemical markers of fatigue, body composition, and safety indicators were also analyzed. Gut microbiota was evaluated using 16S rRNA sequencing and constrained principal coordinates analysis (CPCoA). Results: Four weeks of GU supplementation significantly enhanced exercise performance [(treadmill time ↑ Δ = 10.2–11.7 min versus vehicle (q ≤ 0.0002), grip strength ↑ Δ = 40.4–48.5 g (q ≤ 0.05)] and lean body mass [FFM ↑ at GU-1X (Δ = +0.80%, q = 0.0123)], surpassing the commercial BCAA control. Biochemical analyses indicated reduced exercise-induced lactate accumulation [(post-exercise lactate ↓ Δ = −2.71/−2.18 mmol·L⁻¹, q = 0.0006)]. Gut microbiota profiling revealed distinct shifts in community composition in GU-treated groups, notably with an increased abundance of beneficial taxa such as Lactobacillus and Muribaculum. These alterations reflect the prebiotic activity of seaweed-derived polysaccharides, promoting a healthier gut microbial profile. Notably, GU improved metabolic markers (aspartate aminotransferase, [AST]; lactate dehydrogenase, [LDH]) without inducing toxicity. Conclusions: These findings indicate that GU functions as a dual-action supplement, coupling amino acid-mediated muscle anabolism with microbiome modulation to enhance physical performance and metabolic health. As an upcycled marine product, it presents a sustainable and effective strategy for exercise support. Future studies should include 90-day safety, mechanistic assays, and a preregistered human pilot. Full article

Background/Objectives: Fatigue is the most common systemic manifestation of chronic liver diseases, including metabolic dysfunction-associated steatotic liver disease (MASLD). Fatigue not only adversely affects quality of life in MASLD patients but also complicates the attainment of therapeutic goals and contributes to a worse prognosis. This study aimed to analyze the relationship between clinically significant fatigue and laboratory parameters reflecting systemic inflammation, liver function, body composition, muscle strength, and blood pressure in patients with MASLD. Methods: A total of 154 patients with a confirmed diagnosis of MASLD were enrolled in this study. All participants underwent anthropometric assessment, laboratory testing, abdominal ultrasonography, and point shear-wave elastography. Muscle strength was evaluated using handgrip strength (GS) measurement and the Five Times Sit-to-Stand Test (5TSTS). Skeletal muscle mass (SMM) was quantified using dual-energy X-ray absorptiometry (DXA). Fatigue was evaluated using the Fatigue Assessment Scale (FAS), with scores ≥ 22 indicating clinically significant fatigue. Results: Patients with FAS scores ≥ 22 exhibited significantly lower hemoglobin levels (p = 0.004) and erythrocyte counts (p = 0.011), along with a significantly elevated erythrocyte sedimentation rate (ESR; p = 0.002) and C-reactive protein level (CRP; p = 0.007). Furthermore, MASLD patients with FAS scores ≥ 22 demonstrated significantly reduced relative grip strength (p = 0.012) and took longer to complete the 5TSTS (p = 0.011). Additionally, these patients had higher maximum systolic and diastolic blood pressure values compared to those with FAS scores < 22 (p = 0.028 and p = 0.019, respectively). Conclusions: These findings underscore the multifactorial nature of fatigue in MASLD and highlight the need for a comprehensive management strategy. Such a strategy should include dietary modification, increased physical activity, targeted treatment of systemic manifestations of MASLD, and appropriate management of comorbidities. Full article

Background/Objectives: Nanobubble water (NBW) is being studied increasingly for its potential benefits in sports nutrition. This study aimed to evaluate whether supplementation with ozone-enriched NBW (O₃-NBW) could improve integrated exercise capacity—encompassing endurance performance, muscle strength, and postexercise recovery as well as body composition and metabolic adaptations in mice. Methods: Male ICR mice (n = 24) were allocated into Control, Air-NBW, or O₃-NBW (0.2–1 mg/L ozone) groups for 4 weeks. Results: O₃-NBW treatment considerably enhanced forelimb grip strength and treadmill running endurance compared to the Control group (both p < 0.05). Analyses of body composition revealed a higher proportion of lean mass and muscle glycogen storage in NBW groups, notably with O₃-NBW. Serum markers gathered post-exercise demonstrated a reduction in ammonia and blood urea nitrogen (BUN), suggesting improved nitrogen metabolism. Levels of resting serum creatine kinase (CK) and uric acid were also lower in O₃-NBW mice, indicating potential benefits for muscle recovery. In addition, O₃-NBW treatment significantly enhanced oxygen consumption (VO₂) and reduced the respiratory quotient (RQ), signifying amplified fat oxidation, while also lowering total energy expenditure (all p < 0.05). Spontaneous wheel-running activity remained consistent across all the groups. Conclusions: Taken as a whole, these findings emphasize that O₃-NBW supplementation offers ergogenic and metabolic advantages by improving integrated exercise capacity and efficiency of gas exchange, without adverse effects. Full article

Rheumatoid arthritis (RA) is a highly prevalent chronic inflammatory rheumatic disorder leading to functional impairment and sequels. The search for new biomarkers helping in detecting RA subjects of high risk of functional disability is required. Studies showing high follistatin levels in RA have been described; however, none of them have placed focus on the role of follistatin as marker of deteriorated functionality. We aim to identify whether follistatin concentrations could be a potential biomarker of physical disability and disease activity in RA patients. Fifty-seven female RA subjects and 20 age–gender-matched controls were included in a cross-sectional evaluation. An assessment of clinical characteristics, grip strength, gait speed, and muscle mass was conducted. In RA subjects, disability was assessed using HAQ-DI and active disease using the DAS28-ESR. Follistatin levels were measured by ELISA. We compared (a) RA + functional disability and (b) RA + preserved physical function. Serum follistatin levels were increased in RA subjects compared to controls (175 ± 119 vs. 133 ± 47; p = 0.030). Follistatin levels correlated with deteriorated physical function levels (r = 0.491; p < 0.001) and severe activity (r = 0.344; p = 0.009). The RA + functional disability group, as compared to the RA + preserved physical function group, had higher serum follistatin levels (218 ± 159 vs. 141 ± 59; p = 0.030), lower grip strength (7.9 ± 4.6 vs. 14.5 ± 5.1; p < 0.001), reduced gait speed (0.77 ± 0.20 vs. 0.92 ± 0.20; p = 0.010), as well as higher proportions of tender joints ≥4 (48% vs. 16%; p = 0.008), and higher disease activity scores (3.8 ± 1.5 vs. 2.8 ± 1.2; p = 0.008). We concluded that higher follistatin levels are associated with physical functional impairment and the severity of disease activity in women with RA. Future studies are required to evaluate whether these follistatin levels can be related to other outcomes such as labor disability, hospitalization, and falls. Full article

Background: ETAS^®, a standardized extract of Asparagus officinalis stem, has been found to alleviate cognitive impairment in senescence-accelerated mice prone 8 (SAMP8) and is now considered a functional food in aging. The present study aimed to investigate the impacts of ETAS^® on relieving aging-related muscle atrophy in SAMP8 mice. Methods: The SAMP8 mice were fed a regular diet supplemented with 200 or 1000 mg/kg BW ETAS^®50 for 12 weeks. Grip strength, muscle mass, and molecular markers of protein synthesis, degradation, and mitochondrial quality were assessed. Results: We found that ETAS^® significantly increased grip strength and muscle mass in SAMP8 mice. At the molecular level, ETAS^® significantly upregulated protein synthesis via PI3K/Akt/mTOR/p70S6K and downregulated protein degradation via FoxO1a/atrogin-1 and MuRF-1 and myostatin via NFκB expression. In addition, ETAS^® improved mitochondrial quality via promoting mitochondrial biogenesis genes, oxidative respiration genes, fusion/fission genes, PGC1α, and PINK1 proteins and maintained the autophagic flux via reducing ATG13, LC3-II/LC3-I, and p62. Conclusions: ETAS^® exerts beneficial effects on sarcopenia by modulating the positive protein turnover and improving mitochondrial quality in aging. Full article

Baicalin is a natural flavonoid that has anti-apoptotic and anti-inflammatory effects. It shows some beneficial effects on muscle atrophy. However, its effects on age-related muscle atrophy are poorly understood. In this paper, we investigated whether baicalin exerts protective effect against skeletal muscle atrophy and its underlying mechanisms in aged mice using the grip strength test, histological analysis, and Western blots. Baicalin increased total muscle mass and strength in aged mice. Consistently, the cross-sectional area of quadriceps (QD) muscle significantly increased in both baicalin-administrated groups. Moreover, baicalin induced a shift in muscle fiber size distribution toward large fibers in both groups of mice. Expression levels of muscle atrophic factors, such as myostatin (MSTN) and atrogin-1, as well as pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), were elevated in aged mice, but these increases were reduced by baicalin. While mitochondrial fission regulator, dynamin-related protein 1 (DRP-1), and apoptosis-related protein (apoptotic protease activating factor 1 (Apaf-1)) expressions were higher in aged mice than young mice, and their expression were downregulated following baicalin administration. The comprehensive results of this study suggest that baicalin provides beneficial effects on the treatment of sarcopenia not only by suppressing muscle atrophic factor expression and inflammation but also attenuating DRP-1-mediated mitochondrial fission and apoptosis. Full article

Background: Muscle-specific strength (MSS), defined as muscle strength relative to muscle mass, is a key indicator in the assessment of sarcopenia and functional status, especially in patients with cancer. Dual-energy X-ray absorptiometry (DXA) is the reference method for estimating muscle mass, but its limited accessibility hinders routine use. This study aimed to evaluate the correlation between DXA-based MSS and MSS estimated through more accessible techniques. Methods: A cross-sectional study was conducted in 205 adult oncology outpatients. Muscle strength was assessed by handgrip dynamometry, and muscle mass was estimated using DXA, bioimpedance (BIA), ultrasound, and anthropometry. MSS was calculated by dividing grip strength by each muscle mass parameter. Results: MSS calculated with BIA, body weight, and calf circumference showed very strong correlations with MSS-DXA (r > 0.90). Ultrasound-derived MSS showed only a moderate correlation (r = 0.55; p < 0.01). Similar patterns were observed in both men and women. Conclusions: BIA and anthropometric methods, particularly those using body weight and calf circumference, are reliable and accessible alternatives to DXA for estimating MSS in oncology patients. These tools may help improve the identification and monitoring of sarcopenia in clinical settings with limited resources. Full article

Background/Objectives: Sarcopenic obesity, defined by the coexistence of excessive fat accumulation and progressive muscle loss, is associated with an increased risk of metabolic dysfunction and physical disability. While 5,7-dimethoxyflavone (DMF), a bioactive flavone derived from Kaempferia parviflora, has demonstrated anti-obesity and muscle-preserving properties, its effects on sarcopenic obesity remain unclear. Methods: Four-week-old male C57BL/6J mice were fed a high-fat diet (HFD) for 6 weeks to induce sarcopenic obesity, followed by 8 weeks of continued HFD with the oral administration of DMF. Muscle function was assessed through grip strength and treadmill running tests, while muscle and fat volumes were measured using micro-CT. Mechanistic analyses were performed using gene expression and Western blot analysis. Results: DMF significantly reduced body weight, fat mass, and adipocyte size while enhancing grip strength, endurance, skeletal muscle mass, and the muscle fiber cross-sectional area. In the gastrocnemius muscle, DMF increased the gene expression of peroxisome proliferator-activated receptor gamma coactivator-1α (Ppargc1a) and its isoform Ppargc1a4, thereby promoting mitochondrial biogenesis. It also improved protein turnover by modulating protein synthesis and degradation via the phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin signaling pathway. In subcutaneous and brown adipose tissues, DMF increased mitochondrial DNA content and the expression of thermogenic and beige adipocyte-related genes. These findings suggest that DMF alleviates sarcopenic obesity by improving mitochondrial function and regulating energy metabolism in both skeletal muscle and adipose tissues via PGC-1α-mediated pathways. Thus, DMF represents a promising therapeutic candidate for the integrated management of sarcopenic obesity. Full article

Sport climbing has evolved into a demanding discipline where lower limb performance is increasingly relevant, particularly in indoor bouldering. This exploratory study aimed to identify trends in strength and flexibility variables of the lower limbs in 24 recreational climbers (17 males, seven females), classified by sex and climbing level. Male climbers showed significantly greater performance in all measures of strength and power, including vertical and horizontal jumps, pull-ups, and handgrip strength. In contrast, female climbers demonstrated superior lower-limb flexibility and hip mobility, with significant differences observed when normalized to height. They also showed slightly better ankle dorsiflexion, although this difference was not statistically significant. Climbing level (mean: 6c+) correlated significantly with pull-ups (r = 0.598, p = 0.002), relative grip strength (r = 0.440, p = 0.032), and fat mass (r = −0.415, p = 0.043). Despite the lack of association between lower-limb performance and climbing grade, unilateral tests such as the Hop Test and hip mobility assessments may hold value for injury prevention and movement control. These findings highlight that lower-limb training, particularly strength, unilateral control, and flexibility, should not be excluded from physical preparation in climbing. Preventive strategies focusing on joint stability are especially recommended for female climbers due to their higher joint laxity and increased ACL injury risk. Future research should incorporate climbing-specific assessments and explore these variables in other climber profiles, such as elite, youth, or injured athletes. Full article

Background/Objectives: This systematic review aimed to investigate the relationship between birth size, a marker of prenatal undernutrition, and both physical and cognitive function in individuals aged 60 years and older. Methods: We searched the PubMed and Scopus databases up to November 2024 for prospective cohort studies that included data on birth size and physical or cognitive function in individuals aged 60 or older, excluding studies focused on preterm individuals. The Risk Of Bias In Non-randomized Studies—of Exposure (ROBINS-E) tool was used to evaluate the bias of each included study. Fixed-effects meta-analysis was performed using Review Manager. This systematic review was registered with PROSPERO, CRD42023360823. Results: Twenty-four articles met the eligibility criteria, with participant numbers ranging from 52 to 4000 (about 50% women) and an average age range of 60.9 to 78.4 years. Eight articles had a high risk of bias, while the remaining 16 presented some concerns. Three meta-analyses were conducted: two for grip strength and one for word fluency. Grip strength was positively associated with birth weight, both in an unadjusted analysis, which showed an increase of 1.88 kg (95% CI 1.19, 2.56), and in an analysis adjusted for age, sex, and height/body mass index, which showed an increase of 1.15 kg (95% CI 0.71, 1.59). Word fluency also displayed a positive association with birth weight, with an increase of 0.62 words per minute (95% CI 0.15, 1.10). Conclusions: Smaller birth size, indicative of prenatal undernutrition, is associated with diminished physical and cognitive function in later life. These results highlight the importance of identifying individuals born small as a vulnerable group and implementing lifelong strategies to promote healthy aging. Full article