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Effects of blood flow restriction training combined with plyometric training on lower limb muscle strength and motor unit recruitment in basketball players: An experimental study.

OBJECTIVE: Previous studies have shown that plyometric training (PT) improves neuromuscular function and explosive power but not maximal strength. Blood flow restriction training (BFR) combined with low-intensity resistance training (RT) increases muscle mass and strength. This study investigated the effects of PT, and BFR combined with PT on lower-limb muscle function. METHODS: Twenty elite basketball players were randomly assigned to two groups: PT-alone group (PT, n&#x202f;=&#x202f;10) and BFR combine with PT group (PT-BFR, n&#x202f;=&#x202f;10). All participants underwent bodyweight-based plyometric training three times per week for eight weeks. Peak torque values for hip and knee flexion and extension, as well as root mean square (RMS) values derived from electromyography, were measured before and after the intervention. RESULTS: After the 8-week intervention, both groups showed significant improvements in knee flexion and extension peak torque at 180&#xb0;/s (all p&#x202f;<&#x202f;0.01). Between-group comparisons revealed greater gains in the PT-BFR group for hip extension and flexion at 60&#xb0;/s (p&#x202f;=&#x202f;0.036-0.002; &#x3b7;p2 = 0.225-0.233). RMS of the rectus femoris increased significantly more in the PT-BFR group than in the PT group (right: p&#x2009;=&#x2009;0.004, &#x3b7;p2 = 0.385; left: p&#x2009;=&#x2009;0.020, &#x3b7;p2 = 0.266), whereas no significant changes were observed in the gastrocnemius, tibialis anterior, or biceps femoris (all p&#x2009;>&#x2009;0.05). CMJ height also improved more in the PT-BFR group, with a significant group &#xd7;&#x2009;time interaction (p&#x2009;=&#x2009;0.042, &#x3b7;p2 = 0.210). CONCLUSION: Both training protocols enhanced bilateral lower-limb strength, with notable gains in the non-dominant leg; however, the magnitude did not differ substantially between groups. In contrast, compared with PT alone, BFR combined with PT produced superior enhancements in lower-limb muscle strength and neuromuscular recruitment. These findings suggest that when PT is employed to improve explosive power, it may be effectively combined with BFR to further augment muscular strength.

Humans

Lower-limb electromyographic responses across four recumbent cycling configurations in healthy young men.

Recumbent cycling provides an adjustable configuration in which backrest angle and crank-axis height can alter lower-limb loading. Backrest angle changes the orientation of the active musculature relative to gravity, whereas crank-axis height modifies the foot-pedal interface and the ankle lever arm. Whether such positioning is associated with differences in lower-limb electromyographic (EMG) activation across both factors together has not been examined. Using a randomized crossover design, fifty-nine healthy young men cycled at 100&#xa0;W and 50&#xa0;rpm under four conditions combining two backrest angles (30&#xb0;, 75&#xb0;) and two crank-axis heights (Rh, high, 77&#xa0;cm; Rl, low, 45&#xa0;cm). Surface EMG from the rectus femoris (RF), biceps femoris (BF), and gastrocnemius medialis (GAS) was analyzed for root mean square (RMS) amplitude, absolute onset sequence, and relative recruitment timing (%Sequence, derived using Telescan software and referenced to RF). RMS amplitude did not differ across conditions for any muscle (all p&#xa0;&#x2265;&#xa0;0.356), and absolute onset sequence showed no condition effect (all p&#xa0;&#x2265;&#xa0;0.197). For GAS %Sequence, the Greenhouse-Geisser-corrected omnibus test was significant (F(1.32, 76.56)&#xa0;=&#xa0;28.45, p&#xa0;<&#xa0;0.001), driven by a within-30&#xb0; contrast in which %Sequence was lower under Rl than Rh (paired t(58)&#xa0;=&#xa0;10.39, Holm-adjusted p&#xa0;<&#xa0;0.0001; mean difference 22.0 percentage points, 95&#xa0;% CI [17.8, 26.3]; dz&#xa0;=&#xa0;1.35). Because %Sequence is referenced to RF, this exploratory shift should be interpreted cautiously. Lower-limb activation may be constrained by the closed-chain nature of pedaling, whereas distal recruitment timing may be sensitive to crank-axis height and the foot-pedal interface.

Humans

Age-related differences in motor unit behaviours and maximal strength: A systematic review and meta-analysis.

Ageing is associated with a decline in strength; however, the neural mechanisms underpinning these changes remain poorly understood. Motor unit discharge rate (MUDR) and recruitment threshold (MURT) regulate the magnitude of motoneuron output through rate coding and orderly recruitment, while discharge rate variability (MUDRV) reflects the steadiness of motoneuron output. Yet, age-related differences in these properties remain inconsistent across the literature. Therefore, this systematic review and meta-analysis quantified age-related differences in motor unit behaviours and their contribution to maximal isometric strength. Electronic databases (Medline, Embase, Scopus, PsycINFO, Ovid Emcare, CENTRAL, and Web of Science) were searched up to May 2025, yielding 1493 records; of these, 48 studies met the inclusion criteria. Standardised mean differences (SMDs) were calculated using random-effects models to compare older and younger adults, and methodological quality was assessed using the AXIS tool. Older adults exhibited markedly lower maximal strength than younger adults (SMD = -1.01; 95% CI -1.22, -0.79). MUDR was lower in older adults across all contraction intensities, with greater reductions at high forces (> 60% maximal voluntary contraction (MVC): SMD =&#x202f;-0.65; 95% CI -0.96, -0.34) compared to low forces (< 30% MVC: SMD = -0.34; 95% CI -0.50, -0.18). Discharge rate variability was greater (SMD = 0.44; 95% CI 0.15, 0.72), whereas recruitment thresholds relative to MVC were lower (SMD = -0.42; 95% CI -0.80, -0.03) in older adults. Collectively, these findings suggest that age-related alterations in motor unit discharge behaviour may contribute, at least in part, to reduced maximal strength in older adults.

Aging

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

Foot exercise plus education versus brief advice for the treatment of plantar heel pain (FEET Trial): a feasibility randomised controlled trial.

BACKGROUND: Despite foot muscle strengthening being a target of exercise interventions for plantar heel pain (PHP) no study has measured foot muscle outcomes, and existing research is limited by a lack of control (no treatment) comparisons. OBJECTIVES: To determine the feasibility of conducting a randomised controlled trial and investigate the acceptability and credibility of comprehensive progressive foot exercise and education compared to brief advice for PHP. DESIGN: Randomised parallel group feasibility trial. METHOD: People with PHP were randomised (1:1 concealed allocation) to receive either foot exercise plus education or brief advice for twelve weeks. Primary outcomes included willingness to enrol, recruitment rate, adherence, logbook completion, dropout rate, early withdrawal reasons, adverse events, additional treatments sought, and credibility/expectancy. RESULTS: Twenty people with PHP (16 women; age 50&#x202f;&#xb1;&#x202f;9 years; body mass index&#x202f;=&#x202f;30.7&#x202f;&#xb1;&#x202f;4.6&#x202f;kg/m2) were recruited over 15 weeks (1.3 participants per week). Primary outcomes were willingness to enrol (80%), adherence (physiotherapy sessions attended: foot exercise plus education 85%, brief advice 100%; home exercise program: 62% daily sessions completed, 72% thrice weekly sessions completed), logbook completion (foot exercise plus education 75%, brief advice 90%), dropout rate (15%), and additional treatments sought (69%). There were no intervention-related adverse events, and credibility scores were higher for foot exercise plus education. CONCLUSIONS: This study confirms feasibility and acceptability of a protocol comparing foot exercise plus education with brief advice in individuals with PHP, generating key insights to inform future trial design.

Humans

The Acute Effects of Blood Flow Restriction on Ankle Muscle Reaction Time and Proprioception in Healthy Individuals.

Blood flow restriction (BFR) induces hypoxic and metabolic stress, which may alter afferent feedback and neuromuscular control. However, its acute effects on ankle sensorimotor function remain unclear. The aim of the study was to investigate the acute effects of lower-limb BFR on multidimensional ankle sensorimotor function in healthy adults. Twenty-four participants (12 females, 12 males) completed two conditions in randomized order and a crossover design: BFR at 60% arterial occlusion pressure (AOP) and a control condition (20 mmHg). All measurements were performed during occlusion. Outcomes included joint position sense (active and passive), kinesthesia, static and dynamic balance, lower-limb muscle activation (surface electromyography), and muscle reaction time during sudden ankle inversion. BFR impaired active joint position sense at 20 degrees of inversion (p = 0.011), with no changes at other angles or in kinesthesia. Static balance deteriorated, with increases in sway area (p = 0.017), sway distance (p = 0.029), and sway velocity (p < 0.001), particularly under eyes-closed single-leg stance. Posterolateral reach distance decreased (p = 0.023), accompanied by reduced lower-limb muscle activation. Tibialis anterior muscle reaction time during 30 degrees of inversion in the ankle neutral position was shortened (p < 0.001), whereas peroneus longus muscle responses were unchanged. Acute lower-limb BFR impairs ankle sensorimotor control by reducing proprioceptive accuracy, balance performance, and muscle activation, while shortening reaction time. These findings suggest caution when applying BFR during tasks that require high postural demands or end-range control. Registration number and date: NCT07307339, 12/26/2025.

Humans

Muscle mechanical and architectural adaptations in response to different endurance training modalities in older adults.

INTRODUCTION: This study examined the effects of various cycling endurance training modalities, matched for total workload, on muscle mechanical and architectural characteristics in older adults. METHODS: Fifty healthy participants (25 females, 59-79&#xa0;yrs) were randomly assigned to five age and sex matched groups: one control and four workload-matched training groups (moderate-intensity continuous, heavy-intensity continuous, high-intensity interval, and heavy-intensity continuous in eccentric cycling). Training consisted of three weekly sessions over 8&#xa0;weeks, with evaluations conducted at the beginning and end of the intervention with maximal voluntary isometric contractions at five different knee angles (90, 75, 60, 45, 30&#xb0;) and maximal concentric and eccentric isokinetic contractions at five different knee angular velocities (45, 90, 150, 210, 250&#xb0;/s). Maximum voluntary isometric torque (Tmax) and optimal knee angle (KAopt) were obtained from the isometric contractions; eccentric torque (Tecc) and maximum concentric knee angular velocity (Vmax) were obtained from the isokinetic contractions. The muscle architecture of vastus lateralis (VL) at rest (muscle thickness, pennation angle, and fascicle length) was investigated as well. RESULTS: No statistical differences were detected between groups or time points in VL architecture, in KAopt and in Vmax. A main effect of time was observed for Tmax (p&#xa0;<&#xa0;0.001, &#x3b7;2p&#xa0;=&#xa0;0.458) and Tecc (p&#xa0;=&#xa0;0.002, &#x3b7;2p&#xa0;=&#xa0;0.191) in all the investigated training groups. The within-group comparisons indicate significant increases in Tmax in the training groups, but not in the control group. CONCLUSIONS: Commonly applied endurance exercises improve muscle mechanical capacity (Tmax and Tecc) in older adults, with no structural (architectural) muscle remodelling, when matched for workload.

Humans

Muscle Massage Adding Capacitive Resistive Electric Transfer Therapy in Active or Sham Condition for Post-Exercise Recovery in Athletes: A Crossover Clinical Trial.

The increasing demands of elite sports reduce recovery time, impair performance, and increase injury risk. Efficient lactate transport is essential for postexercise recovery. Capacitive resistive electric transfer (CRET) therapy enhances deep tissue heating, induces vasodilation, and promotes circulation. To evaluate whether adding active CRET to a standardized muscle recovery massage, compared with the same massage plus sham CRET, influences indicators of muscle recovery following a maximal anaerobic effort test. A randomized, single-blind, sham-controlled, and crossover clinical trial was conducted in 25 athletes. Participants completed four visits and, after the maximal power and anaerobic capacity test (Wingate test), received a standardized muscle recovery massage combined with either active CRET or sham CRET. Blood lactate levels, muscle oxygenation, muscle thickness, echogenicity, knee extension force, and muscle activity were assessed before and after the test, after treatment, and 24&#xa0;hours later. Compared with massage plus sham CRET, massage plus active CRET was associated with lower blood lactate concentration at 60&#xa0;min postexercise (p&#xa0;=&#xa0;0.029). Ultrasound-derived muscle thickness and echogenicity also differed between conditions at several time points (p&#xa0;<&#xa0;0.05). However, no significant differences were observed in Wingate test performance, force, muscle activity, and oxygenation between conditions. In athletes performing repeated Wingate exercise, adding active CRET to massage was associated with lower blood lactate concentration at 60&#xa0;min postexercise and with differences in ultrasound-derived muscle thickness and echogenicity compared with sham CRET plus massage. However, these between-condition differences were not accompanied by clear short-term functional recovery benefits. TRIAL REGISTRATION: NCT06906146.

Humans

Characterizing Submental Neuromuscular Activity of Swallowing Rehabilitation: An Electromyographic Evaluation of Rehabilitative Maneuvers in Healthy Adults.

PURPOSE: The effortful swallow (ES), the Mendelsohn maneuver (MM), and isometric tongue presses (TPs) are widely used swallowing maneuvers/exercises to improve elements of swallowing, such as muscle strength and biomechanics. However, the underlying neuromuscular mechanisms of these exercises remain unclear, potentially limiting our ability to specify treatment targets and improve treatment efficacy. This study aimed to compare submental neuromuscular activation patterns during the ES, MM, TPs, and typical swallows in healthy young and older adults. METHOD: As part of a larger randomized crossover validation study, 60 healthy adults (30 young and 30 older) completed typical swallows and three maneuvers using a wearable submental surface electromyographic (sEMG) system (i-Phagia). Outcome variables included (a) normalized mean sEMG amplitude and (b) time to peak sEMG amplitude. Linear mixed models were used to examine effects of task, age, and sex on both outcomes. RESULTS: Normalized mean amplitude was significantly different across tasks. Post hoc pairwise comparisons confirmed that all three maneuvers produced higher normalized mean sEMG amplitude than typical swallows, with the ES eliciting the highest amplitude across age groups. Time to peak amplitude differed significantly across tasks, with typical swallows requiring the shortest time to reach peak amplitude, followed by the ES, MM, and TP. CONCLUSIONS: The ES required the highest neuromuscular effort with the shortest time to reach peak amplitude, suggesting its potential for targeting submental muscle power. Typical swallows required the least neuromuscular effort with the shortest time to reach peak amplitude, suggesting their potential for training submental muscle speed. The MM and TP may also improve submental muscle strength; however, given their temporal requirements (longer durations), they may be more beneficial for targeting coordination and endurance, though more research in this area is warranted. These findings underscore the importance of task-specific neuromuscular profiling to inform mechanism-based swallowing rehabilitation. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.32948549.

Humans

The Efficacy of Erector Spinae Plane Block Versus Subcostal Transversus Abdominis Plane Block in Laparoscopic Nephrectomy: A Randomized Clinical Trial.

OBJECTIVES: This study compared the efficacy and safety of erector spinae plane block (ESPB) versus subcostal transversus abdominis plane (TAP) block in reducing postoperative pain among patients undergoing laparoscopic nephrectomy. METHODS: This randomized clinical trial enrolled 70 adult patients, ASA physical status I or II, who underwent total (radical) laparoscopic nephrectomy under general anesthesia. Patients were randomly assigned to 2 groups. Group ESPB received an ultrasound-guided ESPB at the T7 transverse process level, while group TAP received an ultrasound-guided subcostal TAP block. The primary outcome was the total amount of morphine consumed at 6 and 24 hours postoperatively. Secondary outcomes included the incidence of patients requiring opioid analgesia, time to rescue analgesia, visual analog scale of pain intensity, time to postoperative ambulation, intraoperative and postoperative hemodynamics, arterial partial pressure of oxygen to fraction of inspired oxygen (PaO 2 /FiO 2 or P /F) ratio, and incidence of complications. RESULTS: Compared with the TAP group, the ESPB group exhibited significantly lower median morphine consumption at 24 hours ( P =0.032), prolonged time to first analgesic rescue ( P =0.049), and lower incidence of rescue morphine requirement (OR=0.23; 95% CI=0.06-0.94; P =0.031), with lower visual analog scale pain scores at 12, 18, and 24 hours postoperatively ( P <0.001). The mean arterial blood pressure and heart rates were comparable between groups. No significant adverse effects from either approach. DISCUSSION: In laparoscopic nephrectomy, ultrasound-guided ESPB may safely and effectively be used to improve pain management and reduce pain intensity, with stable hemodynamics and a comparable risk of postoperative complications to the ultrasound-guided subcostal TAP block.

Humans

Genome-wide characterisation of the myosin light chain gene family in Chinese perch (Siniperca chuatsi) and its expression patterns in muscle fibre types and injury response.

The Class II myosin light chain (myl) genes in Chinese perch (Siniperca chuatsi) have not yet been systematically characterised, and relationships with muscle fibre specification, development, and injury-associated remodelling remain unclear. In this study, fast and slow muscle fibres were initially distinguished using myofibrillar ATPase histochemistry. Subsequently, genome-wide mining identified 16 Class II myl genes, comprising eight essential and eight regulatory light-chain subunits. Their conserved-domain features, chromosomal distribution, phylogenetic relationships and expression profiles were analysed. Transcriptomic profiling showed that summed myl transcript abundance was higher in fast muscle than in slow muscle, accounting for 67.2% of the pooled myl transcript pool across the two muscle types (paired t-test, raw P&#xa0;=&#xa0;0.036). mylpfa, myl1 and mylz3 were the major fast-muscle-associated genes, whereas myl10, myl2b and myl13 were preferentially expressed in slow muscle at the transcript level. These patterns support these genes as candidate fibre-type-associated expression markers. Developmental profiling identified stage-associated myl expression patterns, including a possible expression shift between mylpfb and mylpfa. In the descriptive injury-repair time course (d0-d7), FPKM profiles indicated that fast-muscle-associated genes (mylpfa, mylz3 and myl1) were lower at d1 and recovered by d3, whereas several slow-muscle-associated genes showed biphasic transcript-level increases. The slow-muscle-associated RLC gene mylpfb showed a delayed expression peak at d7. Notably, the embryonic isoform myl6l showed a modest increase from approximately 2 FPKM at d0 to 4-5 FPKM after injury, suggesting a possible injury-associated expression pattern that requires further validation. Together, these findings provide a genome-wide description of the Chinese perch myl gene family and identify candidate fibre-type-associated genes and descriptive injury-associated isoform expression patterns.

Animals

Therapeutic Exercise Protocol During Hospitalization in Pediatric Oncohematological Patients: Randomized Clinical Trial.

BACKGROUND: Leukemias, lymphomas, and central nervous system tumors are among the most common pediatric cancers and may lead to motor deficits, impaired balance, reduced muscle strength, fatigue, and decreased functional capacity. Early physiotherapy during hospitalization may help prevent inactivity and support functional preservation in this population. OBJECTIVE: To evaluate the effects of a therapeutic exercise program on quality of life, muscle strength, fatigue, and functional capacity in hospitalized pediatric oncohematological patients. METHODS: Thirty participants aged 8-17&#xa0;years with oncohematological diseases were randomized to an intervention group (IG) or a minimal active physiotherapy comparator group (CG). Assessments included the 6-min walk test, handgrip dynamometry, the PedsQL Multidimensional Fatigue Scale, and the PedsQL Cancer Module at admission and discharge. The IG performed daily 25-min supervised sessions including aerobic, resistance, and breathing exercises with ambulation guidance, whereas the CG received breathing exercises and ambulation guidance. RESULTS: No significant group&#xa0;&#xd7;&#xa0;time interactions were observed for total fatigue or its domains, overall quality of life or its assessed domains, handgrip strength, or six-minute walk test distance. Time-related changes were observed for some outcomes, but these occurred without evidence of differential change between groups and were not interpreted as effects of the structured exercise protocol. No intervention-related adverse events requiring permanent protocol discontinuation were recorded. CONCLUSION: The structured in-hospital therapeutic exercise protocol could be delivered under close clinical supervision without recorded intervention-related adverse events requiring permanent discontinuation. However, the structured protocol did not demonstrate superiority over the minimal active physiotherapy comparator for fatigue, quality of life, muscle strength, or functional capacity. These findings should be interpreted cautiously because of the small sample size, clinical heterogeneity, variable intervention exposure, and limited intervention-fidelity data. TRIAL REGISTRATION: Brazilian Registry of Clinical Trials (ReBEC), RBR-8sxnfyd.

Humans

Acute Performance, Mechanical and Thermal Effects of Isometric Conditioning Versus Standardized Volleyball Pre-Training Activation in Highly Trained Male Players.

This study compared acute performance, neuromuscular, and thermal responses to a maximal isometric conditioning activity (ICA) versus a standardized volleyball pre-training activation (VPA) in highly trained male volleyball players, and to explore putative mechanisms underpinning post-activation performance enhancement (PAPE) considering training load. In a randomized crossover, 14 men (27 &#xb1; 3 y) completed two sessions: VPA (mobility/plyometric drills; 9 min), and ICA comprising 3&#xd7;5&#xd7;3-s maximal isometric back-squat contractions (knee angle 120&#xb0;; 3-min inter-set rest). Countermovement jump (CMJ) height (primary), relative peak power (PP), RSImod, and contraction time (CT) were recorded pre and 3, 6, 9, and 12 min post. Rectus femoris muscle viscoelastic properties and skin surface temperature (SST) were assessed at matched time points. Analyses used repeated-measures ANOVA, responder analysis, correlations, and regression. Period&#xd7;Sequence interactions favored ICA for CMJ and PP when delivered in Period 2 (lower training volume): &#x2206;CMJ was higher under ICA versus VPA (p = 0.005, d = 1.20); PP likewise greater (p = 0.026, &#x3b7;p2 = 0.35). ICA yielded more beneficial responders than VPA (9/14 vs 1/14; McNemar exact p = 0.021). In Period 2, reductions in rectus femoris muscle stiffness independently predicted CMJ gains (&#x3b2;_std = -0.495, p = 0.005), whereas SST changes did not (p = 0.974). RSImod and CT showed no differences. A brief, high-effort isometric squat protocol was associated with superior acute improvements in jump performance compared with a standard volleyball warm-up, but this advantage emerged specifically when the preceding training volume was reduced (Period 2), suggesting that residual fatigue from training may reduce the effects of PAPE. Gains align with neuro-mechanical rather than thermal mechanisms, supporting ICA as a practical, equipment-minimal priming strategy for elite volleyball.

Humans

Mitochondrial dysfunction in muscle cells induced by snoring vibrations.

Snoring-related vibrations have been proposed as a pathogenic factor contributing to upper airway muscle dysfunction in patients with obstructive sleep apnea (OSA). To investigate whether exposure to snoring vibration is linked to muscle weakness, we used an in vitro vibration model to examine its effects on mitochondrial homeostasis in L6 muscle cells at 8, 12, 24, and 48&#xa0;h. The findings were then compared with mitochondrial alterations in the upper airway muscles from snorers and patients with OSA. Proteomic analysis of L6 myoblasts revealed extensive remodeling of the mitochondrial proteome at 8&#xa0;h, affecting pathways involved in oxidative phosphorylation, protein import, ribosome biogenesis, and RNA processing. Respiratory chain remodeling was subunit-specific, with increased abundance of selected components of Complexes I, IV, and V, including NDUFS4, COX5A, and ATP5PD. However, reductions in spliceosome-associated factors, such as SRSF2 and DDX46, along with alterations in mitochondrial ribosomal proteins, indicated impaired RNA processing and protein synthesis. Furthermore, both proteomic and transcriptomic analyses revealed activation of a mechanosensing-mechanotransduction axis, with early upregulation of integrin subunits and mechanosensitive ion channels, followed by transient activation of focal adhesion signaling. Despite transcriptional upregulation of selected Complex IV subunits Cox5a and Cox6a2, this response was accompanied by accumulation of unspliced pre-mRNA, indicating impaired RNA processing efficiency and a decoupling between transcript and protein levels. Real-time Seahorse assay revealed a collapse of mitochondrial respiration and glycolytic reserve at 8&#xa0;h. Although mitochondrial oxygen consumption recovered after 48&#xa0;h, the ability to dynamically upregulate glycolysis remained impaired. In patients, muscle capillarization was impaired, COX activity was reduced, and mitochondrial organization was disrupted. Moreover, transcription of Complex IV subunits COX5A and COX6A2 was, as in vibrated L6 cells, upregulated, suggesting a mismatch between transcript levels and protein expression. We conclude that snoring-induced vibrations are an unrecognized stressor that disrupts mitochondrial homeostasis in muscle by impairing RNA processing, protein synthesis, and mechanotransduction-driven mitochondrial remodeling, leading to transcript-protein uncoupling and likely muscle dysfunction.

Humans

Compound muscle action potential amplitudes in newborn screen positive spinal muscular atrophy.

OBJECTIVE: To evaluate the utility of compound muscle action potential (CMAP) amplitudes as biomarkers of disease severity in newborn screening (NBS)-positive infants with spinal muscular atrophy (SMA). METHODS: We conducted a retrospective review of 21 infants identified through SMA NBS (11 with 2 SMN2 copies and 10 with 3 SMN2 copies). Baseline and serial right median, ulnar, and fibular motor nerve CMAP amplitudes (millivolts, mV) were obtained during the study. Functional outcomes were assessed using the Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP-INTEND). RESULTS: At baseline, infants with 2 SMN2 copies demonstrated significantly lower median, ulnar, and fibular CMAP amplitudes compared with infants with 3 SMN2 copies (p&#xa0;<&#xa0;0.05). In contrast, baseline CHOP-INTEND scores did not differ significantly between the two groups. Prior to genetic confirmation, a right median CMAP amplitude&#xa0;&#x2265;3.2&#xa0;mV predicted&#xa0;&#x2265;3 SMN2 copies. Following treatment, right median and fibular CMAP amplitudes demonstrated significant improvement over time, including in analyses accounting for SMN2 copies number. CONCLUSION: CMAP amplitudes obtained from multiple upper- and lower-extremity motor nerves provided objective electrophysiological measures that distinguished infants with two versus three SMN2 copies, despite similar baseline CHOP-INTEND scores. Furthermore, CMAP abnormalities were detectable in some cases before confirmatory genetic testing results became available. Serial CMAP measurements demonstrated significant longitudinal changes following treatment, whereas functional assessments approached ceiling values, supporting the potential value of electrophysiological monitoring in the era of disease-modifying therapies. SIGNIFICANCE: CMAP assessment is a useful adjunct in the evaluation of infants identified through SMA NBS.

Humans

The effect of combining visuo-vestibular exercises with manual therapy and exercise on sensorimotor function in chronic neck pain: A randomized controlled trial.

OBJECTIVE: To investigate whether adding visuo-vestibular exercises to standard manual therapy and exercise produces superior improvements in sensorimotor function, pain, balance, and functional disability in adults with chronic neck pain. METHODS: This prospective, randomized controlled trial enrolled 58 adults with chronic neck pain (&#x2265;3 months) allocated to a manual therapy and exercise group (MtE; n&#x202f;=&#x202f;29) or MtE plus visuo-vestibular exercises (MtE-VVE; n&#x202f;=&#x202f;29). Both groups completed 12 supervised sessions over six weeks with a daily home exercise programme. Outcomes were assessed at baseline, 6 weeks, and 12 weeks, and included pain intensity (Visual Analog Scale [VAS]), upper extremity reaction time, computerized posturography, the Neck Disability Index (NDI), and cervical muscle endurance. RESULTS: Fifty-four participants (27 per group) completed the study. Both groups improved significantly across all outcomes (p&#x202f;<&#x202f;0.001). At 12-week follow-up, the MtE-VVE group demonstrated superior outcomes: activity-related pain was reduced by an additional 2.00&#x202f;cm (95% CI: 0.75-3.25; p&#x202f;=&#x202f;0.005), bilateral reaction time improved by 1.70&#x202f;s (p&#x202f;=&#x202f;0.001), eyes-open mediolateral sway decreased by 0.50&#x202f;mm (p&#x202f;<&#x202f;0.001), NDI score was 6.30 points lower (95% CI: 3.42-9.18; p&#x202f;<&#x202f;0.001), and cervical flexion and extension endurance improved by 12.00&#x202f;s and 27.70&#x202f;s, respectively (p&#x202f;&#x2264;&#x202f;0.020). CONCLUSION: Adding visuo-vestibular exercises to standard manual therapy and exercise produces clinically meaningful and sustained improvements in activity-related pain, sensorimotor function, postural control, and functional disability in adults with chronic neck pain, and may be recommended as an effective adjunctive intervention.

Humans

Effects of essential amino acid supplementation on musculotendinous recovery following eccentric plantar flexor exercise: a randomized controlled trial.

BACKGROUND: Exercise-induced muscle damage (EIMD) resulting from eccentric contractions leads to transient impairments in muscle function. Essential amino acids (EAAs) stimulate muscle protein synthesis and may support recovery following damaging exercise. However, limited research has examined the effects of EAAs on muscle function following eccentric plantar flexor exercise. The purpose of this study was to examine the effects of EAA supplementation on indirect markers of muscle and musculotendinous recovery following EIMD. METHODS: Thirty-six recreationally active males (age: 21.2&#x2009;&#xb1;&#x2009;2.7&#x2009;years) were randomly assigned to an EAA group (10&#x2009;g of EAAs), placebo (10&#x2009;g of maltodextrin), or control (no supplementation). Supplements were consumed 30&#x2009;minutes before and immediately after an eccentric plantar flexor protocol (4&#x2009;&#xd7;&#x2009;50 repetitions followed by one set to failure) and during the 72&#x2009;hours recovery period. Indirect markers of muscle damage were assessed pre-exercise, immediately post-exercise, and 24, 48, and 72&#x2009;hours post-exercise, consisting of perceived soreness (NPRS), pain pressure threshold (PPT), calf muscle thickness and Achilles tendon thickness (ultrasound), and calf circumference. RESULTS: The eccentric protocol elicited responses consistent with EIMD, including increased soreness (p&#x2009;<&#x2009;0.001), increased calf muscle thickness and circumference (p&#x2009;<&#x2009;0.001), and reduced PPT (p&#x2009;=&#x2009;0.018). EAA supplementation attenuated soreness at 24&#x2009;hours compared with placebo. Calf muscle thickness increased following exercise in both groups; however, swelling returned to baseline by 72&#x2009;hours in the EAA group but remained elevated in placebo (Condition&#x2009;&#xd7;&#x2009;Time, p&#x2009;<&#x2009;0.001). Achilles tendon thickness decreased immediately post-exercise (p&#x2009;=&#x2009;0.005) but was not influenced by supplementation. CONCLUSIONS: EAA supplementation modestly reduced soreness and was associated with faster recovery of muscle swelling but did not influence tendon morphology within 72&#x2009;hours.

Humans

Effects of Time-Based and Distance-Based Repeated Sprint Training on Physical and Physiological Adaptations in Collegiate Basketball Players.

PURPOSE: This study aimed to compare the effects of time-based (TB) and distance-based (DB) repeated-sprint training (RST) on athletic performance adaptations in collegiate basketball players during preseason and to examine whether the 2 training prescriptions produce different levels of homogeneity in the magnitude of individual adaptations. METHODS: Thirty young male basketball players (age = 21.3 [1.4]&#xa0;y) were randomly and equally assigned to 3 groups (n = 10): DB-RST, TB-RST, and an active control group. Participants completed a 7-week RST program performed 3 times per week, consisting of 4 sets of 4 to 9 repetitions per session. The DB-RST group completed each sprint by covering a fixed 35-m distance, whereas the TB-RST group performed each sprint maximally for a fixed 5-second duration. Performance assessments including countermovement vertical jump, 20-m sprint, Illinois change-of-direction speed, reactive strength index, Wingate anaerobic power, and cardiorespiratory fitness were conducted before and after the 7-week training period. RESULTS: Both training groups demonstrated significant performance improvements over the 7-week intervention and relative to the control group (P < .05). Similar gains were observed in the magnitude of adaptations in the countermovement vertical jump, 20-m sprint, Illinois change-of-direction speed, and reactive strength index for the DB-RST and TB-RST groups. Interestingly, the TB-RST group showed more gains than the DB-RST in the magnitude of adaptations in the peak and mean power outputs, as well as cardiorespiratory fitness. Moreover, the TB-RST group showed lower intersubject variability in adaptive responses across the measured performance outcomes following the training intervention. CONCLUSION: Our findings indicate that RST effectively enhances the performance of basketball players, and that implementing a TB-RST protocol is more effective than a DB-RST approach for producing greater adaptations in physiological variables-specifically anaerobic power output and cardiorespiratory fitness-over the 7-week preseason period.

Humans