PubMed HealthSearch

SEARCH · PubMed Health

Results for “Muscle mass”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Skeletal Muscles Do Not Compete for Growth: Activating Additional Muscle Mass Does Not Compromise Changes in Muscle Size.

Kataoka, R, Yamada, Y, Hammert, WB, Sallberg, RW, Kang, A, Song, JS, Kassiano, W, Metcalf, EE, and Loenneke, JP. Skeletal muscles do not compete for growth: Activating additional muscle mass does not compromise changes in muscle size. J Strength Cond Res 40(9): 1043-1049, 2026-This study investigated whether the magnitude of muscle size and strength differed based on the amount of muscle recruited during training sessions. One hundred five untrained individuals were randomly assigned to 1 of 3 groups: low-load unilateral elbow flexion exercise (a) to failure (LL-Failure, n = 36), (b) to failure and low-load knee extension exercise to failure (LL-Failure + Legs, n = 33), or (c) a time-matched nonexercise control (CON, n = 36). Training groups completed 18 supervised sessions over 6 weeks (2 sets at 30% 1 repetition maximum [1RM] to failure). LL-Failure + Legs group performed 4 additional sets of knee extension exercise in each leg (20-30 RM). Muscle thickness on the anterior upper arm (60 and 70% sites) and elbow flexor 1RM strength of the trained arm were measured at pretesting and posttesting. Changes were compared using the ANCOVA function of Bayes Factors for Informative Hypotheses (prevalues as the covariate). Specific hypotheses were evaluated by comparing Bayes factors and the posterior probabilities between models. Six weeks of training led to increases in muscle size and strength. However, performing additional leg exercise did not attenuate the muscle growth in the anterior upper arm (0.19 cm) compared with performing only arm exercise to failure (0.18 cm). Changes in 1RM strength also did not differ between training groups (0.32 and 0.25 kg for LL-Failure and LL-Failure + Legs, respectively). Overall, there was no evidence for competition of adaptations in muscle size and strength under uncontrolled nutritional conditions. Whether greater training volume or limited nutrient intake induces a competition for resources warrants further investigation.

Humans

Impact of Muscle Quality on Muscle Strength and Physical Performance Beyond Muscle Mass or Diabetes Status.

BACKGROUND: Muscle quality, represented by myosteatosis, is recognized as an important factor in sarcopenia. In this study, we aimed to determine the associations between myosteatosis, muscle strength and physical performance among the elderly South Korean population. METHODS: We included 1440 participants (mean age 62.7&#x2009;&#xb1;&#x2009;6.2&#x2009;years) from the Korean Genome and Epidemiology Study (KoGES). Based on the computed tomography attenuation of mid-thigh imaging, the total muscle area (TMA), normal-attenuation muscle area (NAMA), low-attenuation muscle area (LAMA) and inter-intramuscular adipose tissue (IMAT) and its indices were used to evaluate myosteatosis. Muscle strength was evaluated using hand grip strength, whereas physical performance was evaluated through 4-m gait speed, a 30-s sit-to-stand test and 2-min walking test. RESULTS: Of the 1440 patients, 51.5% were women, and 37.2% had diabetes. With aging, the LAMA index gradually increased, and the NAMA index gradually decreased in both men and women (p for trend <&#x2009;0.001). The NAMA index was positively associated, whereas the LAMA and IMAT indices were negatively associated with muscle strength and physical performance after adjusting for age and sex. Higher tertiles of the NAMA index were consistently associated with improved physical performance across all appendicular skeletal muscle tertiles. The relationship between the NAMA index or LAMA index and muscle strength and physical performance did not differ according to diabetic status. Regular exercise was associated with a higher NAMA index and a lower LAMA index in the non-diabetic group; however, no significant difference in muscle quality was observed in the diabetic group in relation to exercise. CONCLUSIONS: Reduced myosteatosis was positively associated with greater muscle strength and better physical performance in both men and women, regardless of muscle mass or diabetes status; improving myosteatosis may be a therapeutic target for the prevention of sarcopenia.

Humans

Risk factors for loss of skeletal muscle mass in patients with chronic kidney disease on a low-protein diet.

OBJECTIVES: A low-protein diet (LPD) is recommended for patients with chronic kidney disease (CKD) to prevent a further decline in renal function. However, its impact on muscle mass in these patients remains unclear. This study investigated the risk factors for loss of muscle mass in patients with CKD on an LPD. METHODS: Eighty-four patients with predialysis CKD (59 men, mean age 61.9 &#xb1; 11.5 y) who participated in a multicenter randomized controlled trial initiated in 2014 were retrospectively reviewed. We collected data on baseline blood and urine tests, body composition, and dietary records at the start and end of the observation period. We evaluated muscle mass using the skeletal muscle index (SMI) and analyzed risk factors for a decrease in SMI during the 24-wk observation period, using logistic regression analysis. Variables with an association (P < 0.1) in univariate analysis, as well as age, sex, use of low-protein rice, and changes in protein intake, were subjected to multivariate analysis. RESULTS: SMI decreased in 50 patients (59.5%) during the observation period. Multivariate analysis identified significant associations of the SMI with serum albumin at baseline (odds ratio 0.11, 95% confidence interval 0.02-0.52, P = 0.004) and changes in energy intake while on the LPD (odds ratio 3.39, 95% confidence interval 1.00-11.43, P = 0.049). CONCLUSIONS: Risk factors for reduced SMI in patients with CKD on an LPD were malnutrition when initiating the LPD and reduced energy intake during its implementation. Clinicians should optimize nutritional status before initiation of an LPD and ensure adequate energy intake throughout treatment.

Humans

A Causal Effect of Serum 25(OH)D Level on Appendicular Muscle Mass: Evidence From NHANES Data and Mendelian Randomization Analyses.

BACKGROUND: Low serum vitamin D status was reported to be associated with reduced muscle mass; however, it is inconclusive whether this relationship is causal. This study used data from the National Health and Nutrition Examination Survey (NHANES) and two-sample Mendelian randomization (MR) analyses to ascertain the causal relationship between serum 25-hydroxyvitamin D [25(OH)D] and appendicular muscle mass (AMM). METHODS: In the NHANES 2011-2018 dataset, 11&#x2009;242 participants (5588 males and 5654 females) aged 18-59&#x2009;years old were included, and multivariant linear regression was performed to assess the relationship between 25(OH)D and AMM measured by dual-energy X-ray absorptiometry. In two-sample MR analysis, 167 single nucleotide polymorphisms significantly associated with serum 25(OH)D at the genome-wide association level (p&#x2009;<&#x2009;5&#x2009;&#xd7;&#x2009;10-8) were applied as instrumental variables (IVs) to assess vitamin D effects on AMM in the UK Biobank (417&#x2009;580 Europeans) using univariable and multivariable MR (MVMR) models. RESULTS: In the NHANES dataset, serum 25(OH)D concentrations were positively associated with AMM (&#x3b2;&#x2009;=&#x2009;0.013, SE&#x2009;=&#x2009;0.001, p&#x2009;<&#x2009;0.001) in all participants, after adjustment for age, race, season of blood collection, education, income, body mass index and physical activity. In stratification analysis by sex, males (&#x3b2;&#x2009;=&#x2009;0.024, SE&#x2009;=&#x2009;0.002, p&#x2009;<&#x2009;0.001) showed more pronounced positive associations than females (&#x3b2;&#x2009;=&#x2009;0.003, SE&#x2009;=&#x2009;0.002, p&#x2009;=&#x2009;0.024). In univariable MR, genetically higher serum 25(OH)D levels were positively associated with AMM in all participants (&#x3b2;&#x2009;=&#x2009;0.049, SE&#x2009;=&#x2009;0.024, p&#x2009;=&#x2009;0.039) and males (&#x3b2;&#x2009;=&#x2009;0.057, SE&#x2009;=&#x2009;0.025, p&#x2009;=&#x2009;0.021), but only marginally significant in females (&#x3b2;&#x2009;=&#x2009;0.043, SE&#x2009;=&#x2009;0.025, p&#x2009;=&#x2009;0.090) based on IVW models was noticed. No significant pleiotropy effects were detected for the IVs in the two-sample MR investigations. In MVMR analysis, a positive causal effect of 25(OH)D on AMM was observed in the total population (&#x3b2;&#x2009;=&#x2009;0.116, SE&#x2009;=&#x2009;0.051, p&#x2009;=&#x2009;0.022), males (&#x3b2;&#x2009;=&#x2009;0.111, SE&#x2009;=&#x2009;0.053, p&#x2009;=&#x2009;0.036) and females (&#x3b2;&#x2009;=&#x2009;0.124, SE&#x2009;=&#x2009;0.054, p&#x2009;=&#x2009;0.021). CONCLUSIONS: Our results suggested a positive causal effect of serum 25(OH)D concentration on AMM; however, more researches are warranted to unveil the underlying biological mechanisms and evaluate the effects of vitamin D intervention on AMM.

Humans

Responsiveness of muscle mass gain to different load intensities of resistance training in older women: A randomized crossover study.

BACKGROUND: Aging is associated with progressive declines in skeletal muscle mass (SMM) and substantial interindividual variability in adaptations to resistance training (RT). However, whether training load intensity influences hypertrophic responsiveness in older adults remains unclear. OBJECTIVE: To investigate the effects of two commonly prescribed RT loading schemes (15RM and 10RM) on estimated SMM adaptations and responsiveness in older women. METHODS: Twenty-seven older women (67.7&#xa0;&#xb1;&#xa0;4.9&#xa0;years; 65.7&#xa0;&#xb1;&#xa0;10.6&#xa0;kg; 154.5&#xa0;&#xb1;&#xa0;5.8&#xa0;cm) completed two 8-week RT interventions performed at 15RM and 10RM in a randomized crossover design, separated by a 12-week detraining period. Estimated SMM was assessed using dual-energy X-ray absorptiometry. Responsiveness was operationally defined using the standard error of measurement, and participants were classified as responders (RP) or non-responders (N-RP) according to changes in estimated SMM. RESULTS: Both loading schemes promoted significant and comparable increases in estimated SMM (15RM: +0.62&#xa0;&#xb1;&#xa0;0.4&#xa0;kg vs. 10RM: +0.43&#xa0;&#xb1;&#xa0;0.3&#xa0;kg). Overall, 61.1% of participants were classified as responders in at least one condition, whereas 38.9% were classified as non-responders. Responsiveness status was consistent across conditions for most participants, with 48.1% classified as responders under both loading schemes and 25.9% as non-responders under both conditions. Only seven participants (25.9%) changed responsiveness status between interventions. No clear pattern indicated a greater likelihood of responsiveness with either loading scheme. CONCLUSIONS: Results suggest that both the 10RM and 15RM RT protocols significantly increase estimated SMM in older women, with no significant differences between training conditions. Although substantial interindividual variability in adaptive responses exists, training load intensity does not appear to meaningfully influence responsiveness status in most individuals. These findings suggest that both loading schemes can be effectively prescribed to promote SMM gains in older women.

Aged

Genetically Predicted Muscle Mass and Function in Relation to Deep Vein Thrombosis: A Two-step Mendelian Randomization Study Highlighting the Mediating Role of BMI.

BackgroundSarcopenia is observationally linked to venous thromboembolism, but the causal architecture and underlying biological pathways remain largely unclear. This study investigated the causal effects of sarcopenia-related traits on lower extremity deep vein thrombosis (DVT) and quantified potential mediating mechanisms.MethodsWe performed two-sample bidirectional Mendelian randomization (MR) and two-step mediation MR using large-scale GWAS data from UK Biobank, EMBL-EBI, and FinnGen. Exposures included appendicular lean mass (ALM), leg fat-free mass (LFM), hand grip strength, and walking pace. Eighteen candidate mediators were screened for indirect pathways.ResultsGenetically predicted higher ALM was significantly associated with increased DVT risk (FinnGen: OR = 1.288, 95% CI: 1.215-1.365, P < 0.001). Similar positive associations were observed for LFM (OR = 1.920-1.954, P < 0.001). By contrast, muscle functional traits - grip strength and walking pace - demonstrated no consistent causal effects. Reverse MR confirmed a unidirectional relationship. Body mass index (BMI) emerged as a pivotal mediator, accounting for 7.58% - 10.50% of the ALM-DVT effect and 52.74% - 62.73% of the LFM-DVT effect. Notably, the independent effect of ALM was largely attenuated after adjusting for metabolic confounders in multivariable MR.ConclusionGenetic predisposition to high muscle mass, rather than functional strength, increases DVT risk. This relationship appears to be significantly driven by metabolic adiposity, suggesting that the "muscle-vascular-coagulation" interaction is partly explained by body-size-related metabolic burden. Risk stratification should integrate muscle mass evaluation with comprehensive metabolic health assessments.

Humans

Celery seed extract attenuates sarcopenic obesity and age-related sarcopenia by reducing intramuscular lipid accumulation in mice.

BACKGROUND & AIMS: Sarcopenia is characterized by progressive loss of skeletal muscle mass and function and is increasingly recognized to be influenced by metabolic disturbances associated with aging and obesity. Intramuscular lipid accumulation has emerged as a key pathological feature linking metabolic dysfunction to skeletal muscle deterioration. Celery seed extract (CSE) possesses anti-obesity, anti-inflammatory, and antioxidant properties; however, its potential role in skeletal muscle metabolism has not been well investigated. This study aimed to determine whether CSE attenuates skeletal muscle deterioration associated with obesity and aging through modulation of intramuscular lipid accumulation and related metabolic pathways. METHODS: Diet-induced obese mice and naturally aged mice were used to evaluate the effects of CSE supplementation. Skeletal muscle mass, grip strength, muscle morphology, intramuscular lipid content, mitochondrial metabolic signaling, inflammatory responses, and muscle protein turnover pathways were assessed using biochemical, molecular, and histological analyses. RESULTS: CSE supplementation significantly improved skeletal muscle mass, grip strength, and muscle fiber cross-sectional area in both obese and aged mice. These improvements were accompanied by reduced intramuscular triglyceride and cholesterol accumulation. Mechanistically, CSE improved mitochondrial metabolic signaling by activating the AMPK-PGC-1&#x3b1; pathway and increasing mitochondrial oxidative phosphorylation proteins. In addition, CSE suppressed inflammatory signaling pathways, including MAPK activation and NLRP3 inflammasome signaling, and improved muscle proteostasis by enhancing myogenic regulators while reducing the expression of proteolytic factors such as MuRF1, Atrogin-1, and myostatin. Correlation analyses further indicated that intramuscular lipid accumulation was closely associated with mitochondrial dysfunction, inflammatory activation, and muscle atrophy. CONCLUSIONS: These findings demonstrate that CSE alleviates skeletal muscle deterioration in both obesity- and aging-associated sarcopenia by reducing intramuscular lipid accumulation and improving mitochondrial metabolism, inflammatory responses, and muscle protein turnover. Targeting intramuscular lipid accumulation may therefore represent a promising nutritional strategy for preventing sarcopenia associated with metabolic and aging-related stress.

AMPK&#x2013;PGC-1&#x3b1;

Comparative Analysis of Primary Sarcopenia and End-Stage Renal Disease-Related Muscle Wasting Using Multi-Omics Approaches.

BACKGROUND: Age-related primary sarcopenia and end-stage renal disease (ESRD)-related muscle wasting are discrete entities; however, both manifest as a decline in skeletal muscle mass and strength. The etiological pathways differ, with aging factors implicated in sarcopenia and a combination of uremic factors, including haemodialysis, contributing to ESRD-related muscle wasting. Understanding these molecular nuances is imperative for targeted interventions, and the integration of proteomic and metabolomic data elucidate these intricate processes. METHODS: We generated detailed clinical data and multi-omics data (plasma proteomics and metabolomics) for 78 participants to characterise sarcopenia (n&#x2009;=&#x2009;28; mean age, 72.6&#x2009;&#xb1;&#x2009;7.0&#x2009;years) or ESRD (n&#x2009;=&#x2009;22; 61.6&#x2009;&#xb1;&#x2009;5.5&#x2009;years) compared with controls (n&#x2009;=&#x2009;28; 69.3&#x2009;&#xb1;&#x2009;5.7&#x2009;years). Muscle mass was measured using bioelectrical impedance analysis and handgrip strength. Five-times sit-to-stand test performance was measured for all participants. Sarcopenia was diagnosed in accordance with the 2019 Consensus Guidelines from the Asian Working Group for Sarcopenia. An abundance of 234 metabolites and 722 protein groups was quantified in all plasma samples using liquid chromatography with tandem mass spectrometry. RESULTS: Muscle mass, handgrip strength and lower limb muscle function significantly lower in the sarcopenia group and the ESRD group compared with those in the control group. Metabolomics revealed altered metabolites, highlighting exclusive differences in ESRD-related muscle wasting. Metabolite set enrichment analysis revealed the involvement of numerous metabolic intermediates associated with urea cycle, amino acid metabolism and nucleic acid metabolism. Catecholamines, including epinephrine, dopamine and serotonin, are significantly elevated in the plasma of patients within the ESRD group. Proteomics data exhibited a clearer distinction among the three groups compared with the metabolomics data, particularly in distinguishing the control group from the sarcopenia group. The ciliary neurotrophic factor receptor was top-ranked in terms of the variable importance of projection scores. Plasma AHNAK protein levels was higher in the sarcopenia group but was lower in the ESRD group. Proteomic set enrichment analysis revealed enrichment of several pathways related to sarcopenia, such as hemopexin, defence response and cell differentiation, in sarcopenia group. Multi-omic integration analysis revealed associations between relevant metabolites, including catecholamines, and a group of annotated proteins in extracellular exosomes. CONCLUSIONS: We identified distinct multi-omic signatures in individuals with ESRD or sarcopenia, providing new insights into the mechanisms underlying ESRD-related muscle wasting, which differ from primary sarcopenia. These findings may support interventions for context-dependent muscle loss and contribute to the development of targeted treatments and preventive strategies for muscle wasting.

Humans

The effect of low birth weight as an intrauterine exposure on the early onset of sarcopenia through possible molecular pathways.

Sarcopenia, a musculoskeletal disease characterized by the progressive loss of skeletal muscle mass, strength, and physical performance, presents significant challenges to global public health due to its adverse effects on mobility, morbidity, mortality, and healthcare costs. This comprehensive review explores the intricate connections between sarcopenia and low birth weight (LBW), emphasizing the developmental origins of health and disease (DOHaD) hypothesis, inflammatory processes (inflammaging), mitochondrial dysfunction, circadian rhythm disruptions, epigenetic mechanisms, and genetic variations revealed through genome-wide studies (GWAS). A systematic search strategy was developed using PubMed to identify relevant English-language publications on sarcopenia, LBW, DOHaD, inflammaging, mitochondrial dysfunction, circadian disruption, epigenetic mechanisms, and GWAS. The publications consist of 46.2% reviews, 21.2% cohort studies, 4.8% systematic reviews, 1.9% cross-sectional studies, 13.4% animal studies, 4.8% genome-wide studies, 5.8% epigenome-wide studies, and 1.9% book chapters. The review identified key factors contributing to sarcopenia development, including the DOHaD hypothesis, LBW impact on muscle mass, inflammaging, mitochondrial dysfunction, the influence of clock genes, the role of epigenetic mechanisms, and genetic variations revealed through GWAS. The DOHaD theory suggests that LBW induces epigenetic alterations during foetal development, impacting long-term health outcomes, including the early onset of sarcopenia. LBW correlates with reduced muscle mass, grip strength, and lean body mass in adulthood, increasing the risk of sarcopenia. Chronic inflammation (inflammaging) and mitochondrial dysfunction contribute to sarcopenia, with LBW linked to increased oxidative stress and dysfunction. Disrupted circadian rhythms, regulated by genes such as BMAL1 and CLOCK, are associated with both LBW and sarcopenia, impacting lipid metabolism, muscle mass, and the ageing process. Early-life exposures, including LBW, induce epigenetic modifications like DNA methylation (DNAm) and histone changes, playing a pivotal role in sarcopenia development. Genome-wide studies have identified candidate genes and variants associated with lean body mass, muscle weakness, and sarcopenia, providing insights into genetic factors contributing to the disorder. LBW emerges as a potential early predictor of sarcopenia development, reflecting the impact of intrauterine exposures on long-term health outcomes. Understanding the complex interplay between LBW with inflammaging, mitochondrial dysfunction, circadian disruption, and epigenetic factors is essential for elucidating the pathogenesis of sarcopenia and developing targeted interventions. Future research on GWAS and the underlying mechanisms of LBW-associated sarcopenia is warranted to inform preventive strategies and improve public health outcomes.

Humans

Impact of creatine supplementation alone or combined with exercise on inflammatory and clinical outcomes in chronic musculoskeletal pain treated in the rheumatological field: a systematic review.

Creatine supplementation has demonstrated ergogenic and anabolic effects in healthy and clinical populations. However, its potential therapeutic role in individuals with chronic musculoskeletal pain treated in rheumatological contexts remains unclear. The aim was to evaluate the efficacy and safety of creatine supplementation on pain, physical function/disability, quality of life, muscle strength, skeletal muscle mass, and inflammatory markers in people with chronic musculoskeletal pain usually treated from the rheumatological field. A systematic review was conducted following PRISMA guidelines. Searches were performed in MEDLINE, Web of Science, CINAHL, Scopus, and EMBASE up to July 2026. Eligible studies were randomized or nonrandomized clinical trials that provided creatine supplementation alone or in combination with exercise as a treatment compared to a control or placebo group. Eight studies (n = 189) were included, encompassing fibromyalgia, osteoarthritis, rheumatoid arthritis, and juvenile idiopathic arthritis. Creatine dosages varied from chronic low-dose to loading protocols (20 g/d, 2-5 g/d). Combined creatine plus resistance training may improve strength, skeletal muscle mass, and quality of life beyond exercise alone in osteoarthritis. Trials on fibromyalgia suggest an increase in muscle strength, but inconsistent effects on pain. Rheumatoid arthritis studies suggest gains in skeletal muscle mass and, in pilot studies, reduced disease activity. No major adverse events were reported. In conclusion, creatine supplementation alone may be insufficient to obtain clinical benefits, while combined with resistance exercise it could offer potential benefits for muscle strength, skeletal muscle mass and certain aspects of quality of life in these clinical conditions. However, evidence on pain and inflammation remains limited; Furthermore, the response across different clinical conditions is heterogeneous, highlighting the need for larger, high-quality trials.

Humans

COVID-19 multi-omics reveal organ-specific responses and biomarkers.

OBJECTIVE: Post-COVID-19 syndrome is characterised by persistent immune dysfunction and multi-organ sequelae. This study aimed to characterise the systemic blood molecular landscape induced by SARS-CoV-2 infection and identify prognostic markers linked to skeletal muscle mass loss, a key driver of poor outcomes. METHODS: We enrolled 30 healthy controls and 307 COVID-19 patients, collecting 422 plasma samples for integrated proteomic and metabolomic profiling to investigate organ-specific molecular alterations in COVID-19. RESULTS: We comprehensively mapped the molecular landscape of COVID-19, encompassing immune, tissue-specific, and metabolic perturbations, and delineated their interactions. Focusing on organ-damage-related molecular patterns associated with disease progression and mortality, we found that skeletal muscle mass loss contributed to poor clinical outcomes of COVID-19 (p&#x2009;<&#x2009;0.0001). Dysregulated arginine metabolism emerged as a key metabolic signature in fatal COVID-19 cases, with GLUL, GOT1, and citrulline showing significant correlation with skeletal muscle mass loss. Longitudinal analyses further revealed that reduced citrulline levels underlie the poor outcome of COVID-19 patients with muscle mass loss. These findings were robustly supported through multiple approaches: Mendelian randomization confirmed causal relationships between citrulline depletion, sarcopenia/fat-free mass loss, and COVID-19 mortality (p&#x2009;<&#x2009;0.05), transcriptomic analyses of SARS-CoV-2-infected golden hamsters (GSE231910) provided additional support in enrichment of arginine biosynthesis (FDR&#x2009;<&#x2009;0.05), and in vitro experiments further demonstrated that citrulline depletion promotes pro-inflammatory M1 macrophage polarisation &#x2014; a key immunological feature of critical COVID-19. Leveraging these insights, we developed a skeletal muscle loss-specific prognostic prediction model for COVID-19 using GLUL, GOT1, and citrulline. This model effectively stratified patients into high- and low-risk groups (p&#x2009;=&#x2009;0.035). CONCLUSION: Our study advances the understanding of COVID-19-induced organ pathophysiology and provides a foundation for developing targeted therapeutic strategies for post-COVID sequelae.

COVID-19

Effects of Blood Flow Restriction Training at Different Levels of Arterial Occlusion Pressure on Body Composition and Athletic Performance in Youth Soccer Players: A Randomized Controlled Trial.

This study aimed to investigate the effects of low-load blood flow restriction training (BFRT) performed at different levels of arterial occlusion pressure (AOP) on body composition, maximal strength, and athletic performance in youth soccer players. Twenty-four male youth soccer players were randomly assigned to 40% AOP group, 60% AOP group, or control group. Participants in the BFRT groups performed lower-limb resistance training at 30% of one-repetition maximum (1RM) under the corresponding pressure conditions, whereas the control group trained without BFR. Training was conducted three times per week for six weeks. Body composition, back squat 1RM, countermovement jump (CMJ), T-test, and 30-m sprint performance were assessed before and after the intervention. Results showed that lower-limb muscle mass increased significantly in both the 40% AOP group (mean change = 0.55 kg, 95% CI: 0.13 to 0.97 kg, P = 0.010) and the 60% AOP group (mean change = 0.83 kg, 95% CI: 0.37 to 1.29 kg, P < 0.001), with the 60% AOP group showing significantly greater gains than the control group (between-group difference = 1.48 kg, 95% CI: 0.40 to 2.56 kg, P = 0.008). Back squat 1RM improved significantly in both the 40% AOP group (mean change = 6.50 kg, 95% CI: 3.90 to 9.10 kg, P < 0.001) and the 60% AOP group (mean change = 9.25 kg, 95% CI: 6.75 to 11.75 kg, P < 0.001), with the 60% AOP group demonstrating superior strength gains compared with the 40% AOP group (between-group difference = 2.94 kg, 95% CI: 0.20 to 5.68 kg, P = 0.048). CMJ height and T-test performance improved significantly in both the 40% AOP group (CMJ: mean change = 2.07 cm, 95% CI: 0.80 to 3.34 cm, P = 0.002; T-test: mean change = -0.23 s, 95% CI: -0.35 to -0.11 s, P = 0.001) and the 60% AOP group (CMJ: mean change = 2.65 cm, 95% CI: 1.00 to 4.30 cm, P = 0.003; T-test: mean change = -0.26 s, 95% CI: -0.38 to -0.14 s, P < 0.001), with no significant differences between the two BFRT groups (all P > 0.05). No significant changes were observed in 30-m sprint performance across groups (all P > 0.05). This study showed that six weeks of low-load (30% 1RM) blood flow restriction training performed at both 40% and 60% AOP was associated with improvements in lower-limb muscle mass, squat strength, and selected aspects of athletic performance in youth soccer players, compared with low-load training without BFR. While both pressure levels elicited comparable improvements in CMJ and agility performance, training at 60% AOP was associated with greater adaptations in lower-limb muscle mass and squat strength, with no additional benefits observed for 30-m sprint performance.

Humans

Multidisciplinary mHealth Rehabilitation for Patients With Abdominal Cancer Who Are Receiving Chemoradiotherapy: Randomized Phase II Trial.

BACKGROUND: Concurrent chemoradiotherapy (CCRT) for abdominal cancer frequently induces muscle loss, weight loss, and malnutrition. OBJECTIVE: This exploratory randomized phase II trial evaluated whether a multidisciplinary, mobile health (mHealth)-based multimodal rehabilitation program could preserve handgrip strength and muscle mass in patients with abdominal cancer undergoing CCRT. METHODS: In this prospective, multicenter, randomized, open-label phase II trial (NCT05325554), 111 eligible patients with abdominal malignancies scheduled for CCRT were randomly assigned (1:1) to receive either multidisciplinary mHealth rehabilitation care (MRC; n=57) or standard care (SC; n=54). The MRC program was delivered by a dedicated multidisciplinary team using the AiNST mHealth platform and wearable heart rate monitors. The primary end point was handgrip strength at the end of CCRT (analyzed with analysis of covariance adjusting for baseline). Secondary end points were exploratory and analyzed without multiplicity adjustment; sensitivity analysis using false discovery rate (FDR) correction was performed. RESULTS: Between February 2022 and April 2023, 111 patients were enrolled. Adherence was high (n=93, 83.9% achieved exercise targets). After adjusting for baseline handgrip strength, the MRC group had significantly higher handgrip strength at the end of CCRT than the SC group (adjusted mean difference 4.87 kg, 95% CI 3.36-6.38; P<.001). Exploratory analyses of secondary end points (without multiplicity adjustment) showed that the MRC group also had better preservation of body weight (P=.005), skeletal muscle mass (P<.001), serum albumin (P=.009), prealbumin (P=.02), and lower rates of hematological toxicity (P<.05), as well as improved psychological status (distress thermometer [DT] and Hospital Anxiety and Depression Scale [HADS]) and nutritional scores (Nutritional Risk Screening 2002 [NRS-2002] and Patient-Generated Subjective Global Assessment [PG-SGA]) at the end of CCRT (all P<.05). All nominally significant secondary end points remained significant after FDR correction (q<.05). These findings are preliminary and should be interpreted with caution due to the open-label design, population heterogeneity, and exploratory secondary analyses. CONCLUSIONS: In this exploratory phase II trial, a multidisciplinary, mHealth-based multimodal rehabilitation program was associated with better preservation of handgrip strength, muscle mass, and nutritional status, as well as lower rates of certain treatment toxicities, compared with SC. However, definitive conclusions are limited by the open-label design, heterogeneity of tumor types, and short follow-up. Larger, blinded phase III trials are needed to confirm these findings.

Humans

Effects of digital health-based exercise interventions on older adults with sarcopenia: Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Sarcopenia, the progressive loss of muscle mass and function, impairs independence in older adults. Digital health exercise interventions are scalable solutions for older adults with sarcopenia. This systematic review and meta-analysis aimed to synthesize the evidence on their efficacy in populations with clinically diagnosed sarcopenia and identify influential intervention characteristics associated with treatment outcomes. METHODS: We systematically searched PubMed, EMBASE, Web of Science, Cochrane Library, CINAHL, CNKI, and Wanfang on May 20, 2026, with no date restrictions. We included randomized controlled trials involving adults aged &#x2265;60 with sarcopenia receiving digital exercise interventions. Two reviewers independently screened studies, extracted data, and assessed risk of bias; analyses were performed using R and Review Manager. RESULTS: Fourteen trials (n&#xa0;=&#xa0;927) were included. Digital interventions showed potential improvements in muscle mass (MD&#xa0;=&#xa0;0.25, 95%CI:0.03-0.46, 95% PI:-0.36 to 0.85), muscle strength (MD&#xa0;=&#xa0;2.14, 95% CI:1.18-3.11, P&#xa0;<&#xa0;0.001), balance ability (SMD&#xa0;=&#xa0;0.31, 95% CI:0.12-0.51, P&#xa0;=&#xa0;0.001), walking performance (SMD&#xa0;=&#xa0;0.55, 95% CI:0.21-0.89, 95% PI:-0.70 to 1.79), and physical function (SMD&#xa0;=&#xa0;0.89, 95% CI:0.08-1.71, 95% PI:-2.33 to 4.12), but not quality of life (SMD&#xa0;=&#xa0;0.08, 95% CI:-0.19 to 0.35, P&#xa0;=&#xa0;0.53). Exploratory subgroup analyses suggested that factors such as supervision, program duration, and measurement tools may influence outcomes; however, formal tests for subgroup differences were generally non-significant, and consistent patterns across all metrics were not observed. CONCLUSION: Digital exercise interventions show potential for managing sarcopenia in older adults, though the very low to moderate certainty of evidence indicates that true effects may differ substantially from observed estimates. This review explores potential roles of intervention design, supervision, and multimodal delivery. Future research should adopt rigorous designs and longer follow-up to validate results and enhance clinical application. TRIAL REGISTRATION: PROSPERO CRD420251135174.

Humans

Exerkine dysregulation links visceral adiposity to skeletal muscle impairment in end-stage heart failure with reduced ejection fraction: proteomic evidence for a cardio-adipose-muscle axis.

BACKGROUND: Heart failure with reduced ejection fraction (HFrEF) is associated with profound alterations in body composition, skeletal muscle dysfunction, and impaired exercise capacity. Exerkines representing exercise-responsive signaling molecules released by skeletal muscle, adipose tissue, and other organs may mediate systemic metabolic communication between tissues. However, their role in advanced HFrEF and their relationship with adiposity and skeletal muscle characteristics remain poorly understood. METHODS: We studied 73 patients with end-stage HFrEF and 16 healthy controls. Body composition was assessed using computed tomography, including visceral (VAT), subcutaneous (SAT), and epicardial adipose tissue (EAT), as well as skeletal muscle quantity (psoas muscle index, PMI) and quality (psoas muscle density, PMD). Functional performance was evaluated using handgrip strength (HGT) and the 6-min walk test (6MWT). Circulating exerkines were quantified using the Olink technology. Associations between proteins and clinical variables were assessed using age- and creatinine-adjusted linear models with false discovery rate correction. RESULTS: Among patients with HFrEF, 36% were obese and 38% exhibited central obesity independent of BMI. Muscle strength and muscle quality were strongly associated with functional capacity. VAT correlated with muscle mass but not with muscle quality or performance. Compared with controls, HFrEF patients demonstrated elevated inflammatory and metabolic stress-related exerkines including CXCL8, CCL2, IL-6, TNF, IL-15, GDF15, FGF21, ANGPTL4, CTSB, DCN, and resistin. In contrast, proteins associated with muscle integrity and regenerative signaling (myostatin, BDNF, IL-7, SPARC) were significantly reduced. In HFrEF patients leptin strongly correlated with adiposity measures. Metabolic stress mediators (GDF15, IL-15, FGF21, CTSB) were inversely associated with muscle quality and functional performance, whereas myostatin positively correlated with muscle quality, strength, and exercise capacity. BDNF was inversely associated with frailty. CONCLUSIONS: Advanced HFrEF is characterized by a dysregulated exerkine network linking adiposity, skeletal muscle quality, and functional performance. Four biologically coherent axes were identified: a leptin-driven adiposity axis, a metabolic stress-muscle quality axis, a myostatin-related muscle function axis, and a neurotrophic frailty axis. These findings support the presence of a systemic cardio-adipose-muscle signaling network in end-stage HFrEF and identify candidate molecular mediators of sarcopenia and functional decline.

Humans

Probiotic supplementation improves body composition, lipid profiles, and fatty acid metabolism in combat sports athletes during the weight reduction phase.

PURPOSE: Pre-competition weight control for combat sports athletes may alter body composition and fatty acid metabolism. Probiotics have shown potential to regulate overall metabolism; however, their specific effects on fatty acid metabolism during weight control in athletes remain unclear. METHODS: Thirty-two combat sports athletes participating in the 4-week weight reduction period were assigned to either the probiotic group (Group E) or the placebo group (Group C). Body composition, lipid profiles, and fatty acid metabolism were measured before and after the 4-week weight reduction phase. RESULTS: All the athletes experienced a decrease in body weight, body mass index (BMI), body fat percentage, and muscle mass following the 4-week weight loss intervention. Notably, a more significant reduction in body fat percentage (p&#x2009;<&#x2009;0.05) was observed, along with lower levels of triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C), specifically in Group E. Weight loss intervention resulted in increased levels of short-chain fatty acids (SCFAs), specifically acetic acid, propionic acid, and butyric acid. Notably, Group E exhibited higher mean values for SCFAs compared to Group C (p&#x2009;<&#x2009;0.05). Additionally, the serum levels of &#x3b3;-linolenic acid and 8,11,14-eicosatrienoic acid were significantly reduced in Group E (p&#x2009;<&#x2009;0.05). In contrast, the majority of free fatty acids (FFAs) showed significant increases, with greater magnitudes of change observed in Group C (p&#x2009;<&#x2009;0.05). CONCLUSION: Probiotic supplementation can improve body composition, enhance SCFAs levels, and decrease circulating FFAs in combat sports athletes, suggesting that probiotics may have a beneficial impact on pre-competition weight management. TRIAL REGISTRATION NUMBER: chiCTR2400079908 (Reg Date:2024-01-16).

Humans

Paradoxical Effect of Myosteatosis on the Immune Checkpoint Inhibitor Response in Metastatic Renal Cell Carcinoma.

BACKGROUND: Treatment for metastatic renal cell carcinoma (mRCC) has shifted from tyrosine kinase inhibitor (TKI) therapy to immune checkpoint inhibitor (ICI)-based therapy, improving outcomes but with variable individual responses. This study investigated the prognostic implications of pretreatment low skeletal muscle mass (LSMM) and myosteatosis in patients with mRCC undergoing first-line ICI-based therapies, comparing outcomes between PD-1 inhibitor&#x2009;+&#x2009;CTLA-4 inhibitor and PD-1 inhibitor&#x2009;+&#x2009;TKI, incorporating single-cell RNA sequencing. METHODS: A retrospective analysis was performed on 90 patients with mRCC treated with ICI-based therapies between November 2019 and March 2023. Patients were grouped based on whether they received PD-1 inhibitor&#x2009;+&#x2009;CTLA-4 inhibitor or PD-1 inhibitor&#x2009;+&#x2009;TKI combinations. LSMM was defined as skeletal muscle index below 40.8&#x2009;cm2/m2 for men and 34.9&#x2009;cm2/m2 for women. Myosteatosis was defined using skeletal muscle density, with cut-off values <&#x2009;41&#x2009;HU for BMI&#x2009;<&#x2009;25&#x2009;kg/m2 and <&#x2009;33&#x2009;HU for BMI&#x2009;&#x2265;&#x2009;25&#x2009;kg/m2. Progression-free survival (PFS) and overall survival (OS) were compared using Kaplan-Meier curves and multivariable models. Single-cell RNA sequencing was performed on pretreatment samples to compare the immune microenvironment between patients with and without myosteatosis. RESULTS: The study cohort (26.7% female; median age: 60.5&#x2009;years) included 59 patients (65.6%) treated with PD-1 inhibitor&#x2009;+&#x2009;CTLA-4 inhibitor and 31 patients (34.4%) treated with PD-1 inhibitor&#x2009;+&#x2009;TKI. LSMM was present in 18.9% of patients, and myosteatosis in 41.1%, with comparable proportions across groups. During follow-up, 29 patients (32.2%) died: 16 in the PD-1 inhibitor&#x2009;+&#x2009;CTLA-4 inhibitor group and 13 in the PD-1 inhibitor&#x2009;+&#x2009;TKI group. The overall 1-year mortality rate was 22.2%, and PFS rate was 53.3%. Myosteatosis predicted poor OS (HR, 5.389; p&#x2009;=&#x2009;0.008) and PFS (HR, 2.930; p&#x2009;=&#x2009;0.022) in the PD-1 inhibitor&#x2009;+&#x2009;TKI group but was protective for PFS (HR, 0.461; p&#x2009;=&#x2009;0.049) in the PD-1 inhibitor&#x2009;+&#x2009;CTLA-4 inhibitor group. LSMM did not significantly affect outcomes in either group. Single-cell RNA sequencing revealed higher CTLA-4 expression in regulatory T cells and more effector memory CD8+ T cells in patients with myosteatosis, whereas patients without myosteatosis had more anti-tumoural non-classical monocytes. CONCLUSIONS: Myosteatosis negatively impacts OS and PFS in patients with mRCC treated with PD-1 inhibitor&#x2009;+&#x2009;TKI therapy but is protective for PFS in those treated with PD-1 inhibitor&#x2009;+&#x2009;CTLA-4 inhibitor therapy. Altered checkpoint expression and immune cell composition associated with myosteatosis may contribute to these differential responses.

Humans