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Acute pre-exercise oral intake of cacao polyphenols attenuates central fatigue development during sustained low-intensity ankle dorsiflexion exercise in healthy young male adults.

This double-blind, randomized, crossover study investigated whether acute cacao polyphenol (CP) ingestion attenuates neuromuscular fatigue in 19 healthy young male adults. After consuming CP or placebo, participants performed sustained isometric ankle dorsiflexion at 25% of maximal voluntary isometric contraction (MVIC) torque until task failure. Neuromuscular function (MVIC torque, voluntary activation [VA%], doublet torque) and electromyographic activity were assessed before, immediately after, and during recovery (1 and 5&#x2009;min). Salivary chromogranin A and &#x3b1;-amylase were measured at baseline and 1&#x2009;min post-task. Only VA% and chromogranin A showed significant condition &#xd7; time interactions (p&#x2009;=&#x2009;0.027-0.039). VA% significantly decreased from before to immediately after the task and 1&#x2009;min post-task in both conditions (p&#x2009;&#x2264;&#x2009;0.002), with significantly higher values in the CP condition than in placebo immediately after and 1&#x2009;min post-task (p&#x2009;&#x2264;&#x2009;0.037). Chromogranin A significantly increased from baseline to 1&#x2009;min post-task in the placebo condition (p&#x2009;<&#x2009;0.001) but not in the CP condition (p&#x2009;=&#x2009;0.083). These findings suggest that acute CP ingestion attenuates the decline in central motor drive and autonomic stress responses following strenuous exercise, without altering performance or peripheral recovery, supporting its potential as a nutritional strategy for modulating central fatigue.

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

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

Comparing the Effects of Push and Hold Isometric Training on Strength and Musculotendinous Adaptations: A Within-Subject Randomized Controlled Trial.

Lum, D, Oranchuk, DJ, Chen, SE, and Kong, PW. Comparing the effects of push and hold isometric training on strength and musculotendinous adaptations: A within-subject randomized controlled trial. J Strength Cond Res 40(9): 1050-1058, 2026-Despite recent interest in delineating pushing (PIMA) and holding (HIMA) isometric muscle actions, training-induced adaptations have not been examined. As such, we compared the strength and morphological adaptations between PIMA and HIMA training. Twenty limbs across 10 adults (5 men, 5 women, age: 31.4 &#xb1; 6.5 years) were randomly assigned to PIMA or HIMA conditions and underwent 12 training sessions over 6 weeks. PIMA required subjects to exert force against a fixed lever while the HIMA limb maintained a set joint angle while resisting an isotonic lever. During each contraction, subjects had to exert force at 70% of maximal voluntary contraction for 20 seconds at an 80&#xb0; knee angle, for 4-6 repetitions. Subjects completed isometric, concentric, and eccentric knee extension assessments for both limbs before and after the intervention. Pre- and postintervention ultrasound scans were performed to determine quadriceps muscle architecture and patellar tendon thickness. Increased isometric torque was found following both conditions (p < 0.05, g = 0.30-0.36), while concentric (p < 0.05, g = 0.31) and eccentric (p < 0.01, g = 0.50) torque only increased following PIMA. Both conditions increased muscle thickness (p < 0.05, g = 0.27-0.88) and vastus lateralis fascicle length (p < 0.05, g = 0.20-0.31). Only HIMA increased patellar tendon thickness (p < 0.05, g = 0.12). The increase in total quadriceps (p < 0.05, g = 0.46) and especially rectus femoris (p < 0.05, g = 1.44) thickness was greater in HIMA. The results suggest that PIMA may be more effective at improving strength, while HIMA may be superior for inducing morphological adaptations. Larger sample sizes and more ecologically valid training programs are warranted to further elucidate potential differences between different isometric types.

Humans

Effects of passive blood flow restriction on muscle function following exercise-induced muscle damage in recreationally active males.

This investigation examined the effects of passive blood flow restriction (pBFR) on indices of exercise-induced muscle damage (EIMD) in recreationally active males. Fifteen males completed six consecutive visits (&#xb1;2&#x2009;hours). Participants completed 3&#x2009;&#xd7;&#x2009;25 maximal, unilateral, isokinetic (60&#xb0;&#xb7;s-1), concentric-eccentric leg extensions on both legs. Each leg was randomly assigned to receive pBFR (80% arterial occlusion pressure) or sham (20&#x2009;mmHg) at 0, 24, 48, 72, and 96&#x2009;hours post-EIMD. Perceived muscle soreness, range of motion (ROM), pain pressure threshold (PPT), concentric peak torque (CPT), and maximal voluntary isometric contraction (MVIC) torque were assessed and analyzed using separate linear mixed-effects models. Perceived muscle soreness increased at 24&#x2009;hours (mean difference [meandiff] = 4.9 au; p&#x2009;<&#x2009;0.001) and recovered by 96&#x2009;hours (p&#x2009;=&#x2009;0.482), with no differences between conditions (p&#x2009;=&#x2009;0.450). ROM (meandiff&#x2009;=&#x2009;-3.1&#xb0;; p&#x2009;=&#x2009;0.040), PPT (meandiff&#x2009;=&#x2009;-1.63 kgf; p&#x2009;<&#x2009;0.001), CPT (meandiff&#x2009;=&#x2009;-27.7&#x2009;Nm; p&#x2009;<&#x2009;0.001), and MVIC torque (meandiff&#x2009;=&#x2009;-30.8&#x2009;Nm; p&#x2009;<&#x2009;0.001) decreased at 24&#x2009;hours, with recovery occurring between 48-96&#x2009;hours. Condition-specific differences were observed for ROM (meandiff&#x2009;=&#x2009;2.5&#xb0;; p&#x2009;<&#x2009;0.001), PPT (meandiff&#x2009;=&#x2009;0.49 kgf; p&#x2009;=&#x2009;0.005), CPT (meandiff&#x2009;=&#x2009;6.2&#x2009;Nm; p&#x2009;=&#x2009;0.020), and MVIC torque (meandiff&#x2009;=&#x2009;7.1&#x2009;Nm; p&#x2009;=&#x2009;0.044), which were greater in pBFR than sham. These findings suggested that pBFR may reduce impairments in ROM, PPT, CPT, and MVIC torque following EIMD, despite a similar recovery trajectory between conditions.

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

Six weeks of isometric resistance training led to evidence of corticospinal but not reticulospinal adaptation in previously untrained adult males.

The latest hypothesis regarding the source of enhanced neural activation from resistance training is the reticulospinal rather than the corticospinal tract, based on invasive animal and emerging human data. The present study employed a six-week isometric resistance training intervention in a randomized controlled design to address this knowledge gap. Thirty-nine healthy, untrained males (age ~23 y, sustained contraction group n = 13, explosive contraction group n = 9, control group n = 17) underwent neuromuscular and electrophysiological testing and completed all study requirements. Maximal isometric torque (MVC) and rate of torque development (RTD) were measured during a familiarization session as well as before and after the six-week period. Transcranial magnetic stimulation was used to assess motor-evoked potential (MEP) area and silent period duration while subjects contracted to 10% of MVC. Loud sound (120&#xa0;dB) was used to modulate MEP area and reaction time to visual stimuli during the StartReact test. Only the intervention groups demonstrated significant improvements in MVC (27%) and RTD (60%) (both P < 0.01), along with reduced MEP area (-&#xa0;21%) and silent period duration (-&#xa0;23%) (both P < 0.01). The sustained contraction group showed reduced modulation of reaction time and increased MEP suppression due to loud sound. Short-term resistance training seemed to reduce cortical inhibition and corticospinal excitability in both training groups. The study showed conflicting changes in measures purported to evaluate reticulospinal functioning. It is recommended to examine different forms of resistance training and longer training exposure in future.

Humans

Voluntary Knowledge Brokering to Promote Evidence-Based Nursing Practice: A Qualitative Study.

Knowledge brokering is a process of connecting knowledge producers with users to facilitate evidence-based practice through relationship building and information sharing. This descriptive qualitative study aimed to clarify knowledge brokering by nurses in Japanese hospitals. Twelve registered nurses in Japanese hospitals participated. They had over 5&#x2009;years' clinical experience, including experience in conducting research, particularly staff research, and education. Data were collected through semi-structured individual interviews and analyzed using qualitative content analysis. The analysis revealed a central theme: continuous efforts to foster empathy among colleagues and spontaneously promote evidence-based practice: multifaceted brokering activities by clinical nurses. Findings identified 10 categories categorized into four interconnected gears: establishing the foundational ground, assessing clinical needs and staff readiness, tailoring and diffusing evidence, and sustaining and evolving evidence-based practice. Even nurses without formal titles voluntarily bridged the research-practice gap, providing new insights into informal brokering. Brokers communicated considerately, balanced evidence with clinical context, negotiated practical compromises, and fostered staff research competency.

Humans

Isometric Exercises for Tendinopathies: A Systematic Literature Review.

PURPOSE: Musculoskeletal disorders are among the most common reasons for medical consultation, with tendinopathies accounting for up to 30% of such presentations. Although exercise remains the cornerstone of management, the most effective modality continues to be debated. Eccentric exercise has long been the mainstay, but the role of isometric exercise in pain modulation and functional recovery remains unclear. This systematic review aims to evaluate the current evidence on the efficacy of isometric exercises in the management of tendinopathies across various anatomic sites. METHODS: A systematic search was conducted in PubMed, MEDLINE, Embase, and the Cochrane Library from inception to August 1, 2025. Eligible studies included randomized controlled trials and prospective or retrospective cohort studies assessing isometric exercise interventions for tendinopathy, with or without comparator groups. Case series and case reports were excluded. Data extracted included participant demographic characteristics, site of tendinopathy, symptom duration, treatment duration, adherence, and outcome measures such as Victorian Institute of Sports Assessment (A, P, or G), visual analog scale, Patient-Specific Functional Scale, 36 item short form health survey (SF-36), and EuroQol 5-Dimension questionnaires. Imaging outcomes (ultrasound or magnetic resonance imaging) were recorded where available. Methodological quality and risk of bias were assessed using the Cochrane Risk of Bias tool in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. FINDINGS: The search identified 304 articles, of which 13 randomized controlled trials met the inclusion criteria, encompassing 336 participants (40% female). Tendinopathy sites included the patellar (n = 4), Achilles (n = 3), lateral elbow (n = 2), rotator cuff (n = 2), wrist extensor (n = 1), and gluteal (n = 1) tendons. Median symptom duration was 23 months (interquartile range, 3-51 months). Intervention periods ranged from a single 45-minute session to 4-month exercise programs. Treatment adherence was high initially (nearly 100%) but declined over time, with 70% of participants in the isometric and 58% in the control (isotonic) groups completing &#x2265;80% of sessions. Pain reduction and functional improvement were statistically significant in only 3 studies. Imaging-based outcomes were inconsistently reported, and study heterogeneity precluded meta-analysis. Overall methodological quality was rated as good in 3 studies and poor in 10. IMPLICATIONS: Current evidence provides limited support for the superiority of isometric exercise in tendinopathy management. Although isometric regimens appear tolerable and may confer short-term analgesic benefits, their long-term efficacy relative to eccentric or isotonic protocols remains uncertain. Future research should prioritize standardized outcome measures, longer follow-up, and uniform diagnostic criteria to strengthen the evidence base for exercise prescription in tendinopathies.

Humans

Characteristics of post-exercise responders versus non-responders following aerobic or isometric exercise in physically inactive adults of African and South Asian descent with high-normal blood pressure or grade I hypertension.

OBJECTIVE: To investigate interindividual variability in post-exercise hypotension (PEH) and to characterise cardiovascular and autonomic differences between responders and non-responders following aerobic and isometric exercise in adults of African and South Asian descent with elevated blood pressure (BP). METHODS: Physically inactive adults of African and South Asian descent living in Suriname (18-65&#x2009;years) with high-normal BP or grade I hypertension participated in a randomised controlled crossover trial. In this randomised cross-over trial, 47 adults (50.1&#x2009;&#xb1;&#x2009;10.8&#x2009;years; 38% male) with high-normal blood pressure or grade I hypertension completed three conditions: aerobic exercise (30&#x2009;min at 40-60% heart rate reserve), isometric handgrip exercise, and a non-exercise control. Ambulatory BP was assessed over 24&#x2009;h. PEH was defined as the net effect: (post-exercise&#x2009;-&#x2009;pre-exercise) - (post-control&#x2009;-&#x2009;pre-control). Participants were classified as responders if daytime BP decreased &#x2265;5&#x2009;mmHg. Arterial stiffness, cardiac, and autonomic parameters were assessed. RESULTS: Following aerobic exercise, 46% of participants were classified as systolic responders compared with 28% after isometric exercise. No baseline differences were observed in demographic or clinical characteristics between responders and non-responders, suggesting that PEH variability may reflect underlying physiological rather than clinical differences. Aerobic responders demonstrated greater reductions in aortic augmentation index (-19.4% vs. -10.9%, p&#x2009;=&#x2009;0.05), larger increases in stroke volume (+8.1 vs. -5.3&#x2009;mL, p&#x2009;=&#x2009;0.05) and cardiac output (+1.54&#x2009;&#xb1;&#x2009;1.89 vs. +0.58&#x2009;&#xb1;&#x2009;1.60&#x2009;L/min, p&#x2009;=&#x2009;0.009), and more favourable autonomic recovery. Among all variables, only the change in cardiac output was associated with PEH magnitude (r&#x2009;=&#x2009;-0.46, p&#x2009;=&#x2009;0.006). No consistent physiological differences were observed following isometric exercise. CONCLUSION: PEH following aerobic exercise is characterised by a distinct responder phenotype associated with greater reductions in aortic augmentation index and favourable cardiac adaptations. These findings highlight substantial interindividual variability in BP responses and support the need for individualised exercise strategies in hypertension management.

Adolescent

The impact of acute sleep fragmentation on muscle blood flow responses to handgrip exercise.

Sleep fragmentation is reported to impair resting vascular function. The aim of this study was to test the hypothesis that acute sleep fragmentation would impair muscle blood flow during exercise. Twenty adults (10 females and 10 males) participated in a randomized crossover study that included one night of habitual sleep and one night of fragmented sleep. Sleep was assessed at home using wrist actigraphy. Arousals from sleep were increased by an audio alarm sounding every 30 min. The morning following each sleep condition, participants performed single handgrip contractions and rhythmic handgrip exercise at 15%, 30%, and 45% MVC. Forearm blood flow (FBF) was measured using Doppler ultrasound. Nightly awakenings and wake after sleep onset significantly increased by 18% and 43%, respectively, after fragmented sleep, leading to lower sleep duration (P < 0.001). Peak FBF and total hyperemic responses following single contractions were similar between sleep conditions (all P > 0.05). During rhythmic handgrip exercise, brachial artery dilation was reduced after fragmented sleep (main effect: 5.5 &#xb1; 4.8 vs. 3.3 &#xb1; 3.7%; P = 0.01), leading to a lower FBF response to rhythmic exercise (main effect: 122 &#xb1; 58 vs. 110 &#xb1; 56 mL/min; P = 0.04). Endothelial sensitivity to shear rate was similar between sleep conditions (habitual vs. fragmented: 0.039 &#xb1; 0.024 vs. 0.042 &#xb1; 0.031%/s-1; P = 0.77). In summary, acute sleep fragmentation decreases skeletal muscle blood flow during exercise. This finding suggests that blunted oxygen delivery may be a contributing factor for exercise performance deficits after disturbed sleep.NEW & NOTEWORTHY We demonstrate that one night of fragmented sleep decreases steady-state blood flow and vascular conductance during low- to moderate-intensity handgrip exercise. This impairment was not due to an impaired rapid vasodilation to single contractions nor altered endothelial sensitivity to shear rate as these variables were unchanged after acute sleep fragmentation. These results reveal a negative impact of disrupted sleep on the steady-state muscle vasodilatory response to rhythmic contractions.

Humans

Impact of oxytocin discontinuation on fetal heart rate and uterine contractility: A pre-specified ancillary analysis embedded within a randomized trial.

INTRODUCTION: Oxytocin is widely used to augment uterine contractions during labor. However, its use has been associated with fetal heart rate (FHR) abnormalities and neonatal morbidity, which may be reduced by discontinuing oxytocin during labor. We aimed to assess the impact of oxytocin discontinuation at the onset of the active phase of labor on FHR patterns and uterine contractility. MATERIAL AND METHODS: This study is a pre-specified ancillary analysis of the STOPOXY trial, a multicenter, randomized, open-label, controlled superiority trial conducted in 21 French maternity units between January 2020 and January 2022, which aimed to assess the impact of oxytocin discontinuation during active labor on neonatal morbidity. Participants who received oxytocin before 4&#x2009;cm dilation were randomly assigned (1:1) to either oxytocin discontinuation or oxytocin continuation. For the present analysis, we included women from the per-protocol discontinuation group of the parent trial. Inclusion was restricted to the six centers with electronic cardiotocography storage where valid cardiotocography recordings were available for at least 1&#x2009;h before and 1&#x2009;h after oxytocin discontinuation. Using a paired before-and-after design, FHR parameters (classified according to FIGO criteria) and uterine activity were compared during the 60&#x2009;min preceding versus the 60&#x2009;min following oxytocin discontinuation by independent obstetricians blinded to neonatal outcomes. Changes in FHR pattern were categorized as no change, improvement, or deterioration. RESULTS: 284 women fulfilled the eligibility criteria. Following oxytocin discontinuation, mean FHR increased (135 vs. 137.5&#x2009;bpm; p&#x2009;<&#x2009;0.002) and FHR variability significantly changed (p&#x2009;=&#x2009;0.010), with a lower rate of reduced variability (3.9% vs. 2.5%) and a higher rate of normal variability (48.2% vs. 53.3%). The proportion of tracings with decelerations significantly decreased (64.1% vs. 48.6%; p&#x2009;<&#x2009;0.001). Uterine activity decreased, with fewer uterine contractions (4.0 vs. 3.5 contractions per 10&#x2009;min; p&#x2009;<&#x2009;0.001). CONCLUSIONS: Among women receiving oxytocin during early labor, discontinuation at the onset of the active phase was associated with improved FHR patterns and reduced uterine activity, suggesting a lower fetal stress and tachysystole. Further studies are needed to assess whether these changes affect labor management or maternal experience.

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

The Effects of Intermittent Hypoxic Training Strategies on Maximal Oxygen Uptake in Healthy Humans: A Meta-analysis with Meta-regression.

BACKGROUND: Intermittent hypoxic training aims to enhance exercise performance and health, commonly assessed through maximal oxygen uptake (VO2max). Currently applied methods are live-high train-low (LHTL), live-low train-high (LLTH) and passive hypoxic conditioning (PHC). However, within these methods, numerous modes of application exist, and effectiveness is debated. OBJECTIVE: To determine the effect of LHTL, LLTH and PHC on VO2max in healthy participants, and identify factors associated with the amplitude of change in VO2max. METHODS: We conducted a systematic review with random-effects meta-analysis and meta-regression. Studies were identified through PubMed, EMBASE and Web of Science. We included controlled studies, calculating between-group standardised mean differences. Athlete and non-athlete populations were analysed separately. RoB2 was used to assess study quality and publication bias was investigated with funnel plots and the Egger's test. RESULTS: Of the 5244 identified studies, 62 were included for analysis, resulting in a sample size of 1332 participants (610 athletes, 722 non-athletes). LHTL increased VO2max significantly more than control in athletes (mean difference [MD]&#x2009;=&#x2009;2.17; 95% CI&#x2009;=&#x2009;0.77, 3.56) but not in non-athletes (MD&#x2009;=&#x2009;3.1; 95% CI&#x2009;=&#x2009;&#x2009;-&#x2009;0.23, 6.43). LLTH did not increase VO2max significantly more than control in athletes (MD&#x2009;=&#x2009;0.89; 95% CI&#x2009;=&#x2009;&#x2009;-&#x2009;0.27, 2.05) but it did in non-athletes (MD&#x2009;=&#x2009;1.70; 95% CI&#x2009;=&#x2009;0.85, 2.54). PHC did not increase VO2max significantly more than control in athletes (MD&#x2009;=&#x2009;&#x2009;-&#x2009;1.07; 95% CI&#x2009;=&#x2009;&#x2009;-&#x2009;3.51, 1.37) but it did in non-athletes (MD&#x2009;=&#x2009;2.26; 95% CI&#x2009;=&#x2009;1.00, 3.52). Multivariate meta-regressions identified the severity, duration, and frequency of hypoxic exposure to be significantly associated with the change in VO2max. CONCLUSIONS: LHTL showed a significant effect on VO2max in athletic populations while LLTH and PHC showed a significant effect on VO2max in non-athletic populations only. Future studies should target investigating which characteristics (e.g. severity, duration) of the hypoxic exposure are most beneficial.

Journal Article

Effects of exercise on aerobic capacity in people with prehypertension or hypertension: a systematic review and meta-analysis of randomized controlled trials.

This study aimed to quantify the effects of exercise on aerobic capacity in people with prehypertension or hypertension and to identify exercise prescription parameters that optimize improvements. A comprehensive search was conducted in PubMed, Web of Science, Embase, Cochrane Library, and Scopus from inception to 24 October 2025. Data were pooled using standardized mean differences (SMDs) with 95% confidence intervals (CI). Fifteen studies met the inclusion criteria. Exercise significantly improved aerobic capacity in people with prehypertension or hypertension (SMD&#x200a;=&#x200a;0.88; 95% CI: 0.61-1.15; P &#x200a;<&#x200a;0.00001), with multicomponent training demonstrating superior efficacy. Exploratory subgroup analyses suggest that longer programs (&#x2265;12&#x200a;weeks), lower frequency (<3&#x200a;sessions/week), 60-min sessions or longer, total weekly exercise less than 180&#x200a;min, and professional supervision may be associated with better outcomes.

Humans

Comparative genomics and full-length transcriptome profiling of wing morphs in Tetrix grossus (Orthoptera: Tetrigidae).

Wing polymorphism represents a paradigmatic dispersal-reproduction trade-off, yet its molecular basis remains uncharacterised in the phylogenetically distant pygmy grasshoppers (Tetrigidae). Here we integrate comparative genomics across ten orthopteran species with full-length transcriptomics of long-winged (FL) and short-winged (FS) Tetrix grossus. OrthoFinder recovered 118 orthogroups specific to T. grossus. Against a backdrop of pronounced gene-family contraction (36 expansions versus 222 contractions; net -186, mirrored at the ancestral Tetrix node, +37/-140), we identified an ancestral, Tetrix-specific expansion of hormone-regulation (12 genes; fold enrichment 7.93) and lipid/carbohydrate-metabolic families organised into syntenic clusters, alongside 513 positively selected genes enriched for integrin-mediated cell adhesion (6 genes), a process relevant to epithelial and appendage morphogenesis. Full-length transcriptomics of one long-winged (FL) and one short-winged (FS) adult female detected 7530 (FL) and 7515 (FS) expressed genes, with 794 FL- and 776 FS-restricted transcriptome-derived SNP-associated genes. The FL morph was enriched for an EGFR/Ras-Rho developmental-patterning axis and neuromuscular flight genes, whereas the FS morph was enriched for insulin/peptide-hormone response and growth-regulatory loci. Overall, we present genomic resources and testable hypotheses concerning the evolution and regulation of wing morphs in Tetrigidae rather than a validated genetic architecture of wing-morph determination.

Animals

Optimising Exercise Prescription: A Meta-Analysis Examining the Dose Response of Exercise Duration on Cardiorespiratory Fitness Following HIIT and MICT.

BACKGROUND: High-intensity interval training (HIIT) is often promoted as a time-efficient alternative to moderate-intensity continuous training (MICT) for improving cardiorespiratory fitness, yet the duration of HIIT sessions varies considerably across studies. OBJECTIVE: We aimed to characterise the dose-response relationship between exercise session duration and the improvement in cardiorespiratory fitness for HIIT and MICT. METHODS: A dose-response meta-analysis of randomised controlled trials comparing exercise duration in HIIT and MICT, following Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and registered in PROSPERO (CRD42022335590). Effect sizes were calculated using a random-effects meta-analysis. The primary outcome was maximal oxygen uptake (VO2max). Secondary outcomes included blood pressure, lipid profiles, glucose metabolism markers and body composition measures. A one-stage random-effects dose-response meta-analysis was performed to examine the relationship between exercise duration and adaptations. We searched PubMed and Google Scholar; eligibility criteria for selecting studies were randomised controlled trials in humans, published in English and exercise interventions lasting at least 4&#xa0;weeks. RESULTS: We identified 69 randomised controlled trials (2387 participants). High-intensity interval training elicited greater improvements in VO2max than MICT (d = 0.38, 95% confidence interval 0.27-0.49, p < 0.001). High-intensity interval training demonstrated a non-linear dose-response relationship between exercise session duration and VO2max, with 80% of maximal effect (changes in VO2max = 3.45&#xa0;mL/kg/min) achieved with only ~11&#xa0;min/session (95% confidence interval 9.5-40.2). Moderate-intensity interval training showed a linear dose-response relationship between exercise session duration and VO2max, requiring ~52&#xa0;min/session to achieve 80% of the&#xa0;maximal observed&#xa0;effect (95% confidence interval 30.4-55.8). The dose-response relationship was consistent across populations. High-intensity interval training and MICT had comparable effects in improving cardiometabolic risk factors. CONCLUSIONS: High-intensity interval training demonstrated a non-linear dose response, with 80% of maximal effect on VO2max in ~11&#xa0;min/session, whilst MICT required four to five times longer to reach similar responses. The different types of training had comparable effects on cardiometabolic risk factors.

Journal Article