European Journal of Applied Physiology最新文献

{"title":"Increased deep muscle activity with interference low-frequency electrical muscle stimulation: evaluation by positron emission tomography.","authors":"Yuichi Nishikawa, Junsuke Nakase, Takuya Sengoku, Seigo Kinuya","doi":"10.1007/s00421-025-05847-6","DOIUrl":"https://doi.org/10.1007/s00421-025-05847-6","url":null,"abstract":"<p><strong>Background: </strong>The effects of electrical muscle stimulation (EMS) devices that efficiently promote deep muscle contraction have not been characterized. The purpose of this study was to clarify using [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) whether interference with low-frequency EMS can promote muscle metabolism in deep.</p><p><strong>Method: </strong>A total of 16 healthy males were randomly assigned to the EMS group (n = 8, age = 29.8 ± 4.1 years) or the control group (n = 8, age = 26.1 ± 5.0 years). Individuals in the EMS group received interference low-frequency EMS for 20 min each day over a span of three consecutive days as part of the pretest phase. On the measurement day, an EMS was conducted for 10 min, followed by an injection of FDG and then another EMS for an additional 10 min. The control group remained in a seated position for 10 min, after which FDG was administered intravenously. Images from PET-computed tomography were acquired in each group 60 min after the injection of FDG. Regions of interest were delineated in each muscle of the lower extremities. We analyzed the metabolism of each skeletal muscle sample by employing a standardized uptake value.</p><p><strong>Results: </strong>Compared with the control group, the EMS group showed increased glucose metabolism in both superficial and deep muscles of the trunk, pelvis, and lower extremities, as measured by FDG uptake.</p><p><strong>Conclusion: </strong>This exploratory study suggests that low-frequency interference EMS may increase glucose metabolism in deep and superficial muscles of the trunk, pelvis, and lower extremities.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144283105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effects of acute and chronic oral tea catechins and ornithine supplementation on exercise-induced ammonia accumulation and cycling performance in healthy young men: a randomized, double-blind, cross-over, placebo-controlled trial.","authors":"Chihiro Nagayama, Yuka Hamada, Kayoko Kamemoto, Takahiro Hasumura, Yoshihiko Minegishi, Yuji Matsui, Noriyasu Ota, Masashi Miyashita","doi":"10.1007/s00421-025-05833-y","DOIUrl":"https://doi.org/10.1007/s00421-025-05833-y","url":null,"abstract":"<p><strong>Purpose: </strong>This study examined the effects of acute and chronic oral intake of tea catechins and ornithine supplementation on exercise-induced ammonia accumulation and cycling performance.</p><p><strong>Methods: </strong>Sixteen healthy young men participated in a randomized, double-blind, cross-over, placebo-controlled study. For the acute trials, the participants consumed either tea catechins and ornithine (CO) or placebo (P) and performed cycling exercises at an intensity corresponding to 75% of the maximum heart rate for 60 min, followed by a 15-min cycling performance test. The participants continued to consume each designated supplement for 13 days. For the chronic trials, the participants repeated the same protocol as the acute trials on day 14. After a washout period, the participants changed the supplement and repeated the same protocol as above.</p><p><strong>Results: </strong>Plasma catechins (acute ES = 3.61; chronic ES = 2.64, p < 0.001) and ornithine (acute ES = 4.28; chronic ES = 2.25, p < 0.001) concentrations were higher in both acute and chronic CO trials than those in P trials. No differences were found in plasma ammonia concentration measured during the whole experimental period and in mean power output during the performance test among trials. Subjective fatigue during 60-min cycling was lower in both acute and chronic CO trials than those in P trials (acute ES = 0.32, chronic ES = 0.60, p < 0.001).</p><p><strong>Conclusions: </strong>A single dose and 14-day oral intake of tea catechins and ornithine supplementation did not suppress exercise-induced ammonia accumulation or enhance cycling performance.</p><p><strong>Clinical trial: </strong>Clinical trial registration ID: UMIN000035267.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144283107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immediate effects of passive stretching and/or local vibration on ankle range of motion, calf muscle stiffness and passive torque: a randomized controlled cross-over trial.","authors":"Daniel Jochum, Andreas Konrad, Josef Fischer, Stanislav D Siegel, Konstantin Warneke","doi":"10.1007/s00421-025-05839-6","DOIUrl":"https://doi.org/10.1007/s00421-025-05839-6","url":null,"abstract":"<p><strong>Purpose: </strong>Vibrational stimulation was suggested sufficient to acutely enhance range of motion (ROM). However, the actual merit of superimposed vibration and underlying mechanical or sensory mechanisms of ROM increases due to local vibration are not well understood.</p><p><strong>Methods: </strong>Using a randomized controlled cross-over trial, this study opposed two minutes of stretching + vibration (STV) to vibration (V) and stretching (ST) alone as well as a passive control (CG) in 30 healthy, recreationally active participants. Pre- and post-intervention measurements of ankle dorsiflexion ROM, ankle passive torque, and gastrocnemius medialis muscle stiffness were conducted using a dynamometer and shear wave elastography, respectively.</p><p><strong>Results: </strong>All interventions significantly increased ROM (p < 0.001, η² = 0.622) compared to CG, with no additional benefits observed for vibration combined with stretching compared to stretching or vibration alone. However, combining stretching and vibration produced the most pronounced reductions in passive torque over the whole ankle ROM. The combination demonstrated additive effects of stretching and vibration, which affected passive torque in the end ROM and at rest, respectively. Muscle stiffness decreased, but did not differentiate between conditions.</p><p><strong>Conclusion: </strong>These findings negate additional acute vibration effects on ROM that surpass the effects of stretching alone, while the combination of stretching and vibration presented the most prominent influence on passive torque and joint resistance. Vibration also increases stretching pain tolerance; this might facilitate the conduction of exercises and improves compliance as well as adherence to stretching habits.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144274536","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can measurement errors explain variance in the relationship between muscle- and tendon stiffness and range of motion?-a blinded reliability and objectivity study.","authors":"Konstantin Warneke, Julia Meder, Gerit Plöschberger, Manuel Oraže, Maximilian Zechner, Daniel Jochum, Stanislav D Siegel, Andreas Konrad","doi":"10.1007/s00421-025-05814-1","DOIUrl":"https://doi.org/10.1007/s00421-025-05814-1","url":null,"abstract":"<p><strong>Introduction: </strong>The relationship between range of motion (ROM) and underlying parameters such as stiffness (ST) remains controversial throughout the literature. Therefore, this study aimed to analyze the potential role of accumulated measurement errors and subjective influences through a comprehensive assessment of both systematic and random errors on the correlation between tissue ST and ROM.</p><p><strong>Methods: </strong>A total of 75 subjects participated in this double-blinded reliability evaluation. Besides muscle thickness assessments, lower legs' ST in the calf muscle and Achilles tendon (shear-wave elastography [SWE] and viscoelastic parameters [MyotonPRO], respectively) were correlated with ankle dorsiflexion ROM (knee-to-wall test [KtW]).</p><p><strong>Results: </strong>Ultrasound image acquisition (i.e., muscle thickness and ST) and myotonometry showed intrasession reliability (ICC = 0.93-0.99 and 0.72-0.99, respectively) depending on the device. Only for MyotonPRO, there were meaningful systematic and random errors only for decrement (SEM = 0.002-10.629; MAE = 0.01-24.84). ROM showed ICC > 0.99, while for all parameters interday reliability declined (ICC = 0.395-0.88). Interrater objectivity showed ICC = 0.61-0.91 for ultrasound analysis and 0.66-0.96 for myotonometry. No agreement (ICC = 0-0.09) between different ST measurements was observed, while relationship between ST and ROM depended on the investigator (r = 0.21-0.26 versus r = - 0.02--0.07).</p><p><strong>Discussion: </strong>While aligned with reliability and objectivity metrics from the literature, our results demonstrate that ST determination is device-dependent, and its relationship with ROM varies by measurement day and investigator. This underlines clinically relevant measurement errors in ST evaluation, calling for advance standardization to improve reliability and objectivity, while measurement errors quantified beyond the ICC must not be neglected in future studies.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144274535","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Internal training exposure: development and construct validation of an individualised method using heart rate variability.","authors":"Samrat Sheoran, Antonis Stavropoulos-Kalinoglou, Josh Darrall-Jones, Dan Weaving","doi":"10.1007/s00421-025-05841-y","DOIUrl":"https://doi.org/10.1007/s00421-025-05841-y","url":null,"abstract":"<p><strong>Purpose: </strong>The aim was to develop and validate an individualised internal training exposure method by deriving weighting factors for each heart rate (HR) from detrended fluctuation analysis of heart rate variability (DFA-α1) during a graded exercise test.</p><p><strong>Methods: </strong>Thirty-seven participants (17 females; 32.72 ± 9.26 years; maximal oxygen uptake, <math><mover><mi>V</mi> <mo>˙</mo></mover> </math> O_2max = 48.32 ± 7.95 mL kg^-1 min^-1) completed a step- and a ramp incremental test to measure blood lactate (BLa), DFA-α1, and cardiorespiratory fitness (CRF) variables, i.e. speed at lactate, ventilatory thresholds (LTs/VTs), and <math><mover><mi>V</mi> <mo>˙</mo></mover> </math> O_2max. Exponential fitting of the fractional elevation of HR (ΔHR) with BLa (individualised training impulse; iTRIMP) or DFA-α1 (αTRIMP) generated individualised coefficients for both methods. The TRIMP weightings were interpolated values of BLa or DFA-α1 derived at each ΔHR through coefficients to represent individualised physiological intensity. Principal component regression evaluated the relationship between combined CRF variables and the TRIMP coefficients or weightings.</p><p><strong>Results: </strong>Large inter-individual variation was observed at the same physiological thresholds (ΔHR at LT₁/VT₁ = 0.51-0.83 and LT₂/VT₂ = 0.63-0.96), underscoring the need for TRIMP methods to weight ΔHR and account for different exposure at similar intensity. CRF had a moderate relationship with coefficients for iTRIMP and αTRIMP methods (R²_average = 0.52-0.67), but a moderate to strong relationship with their weightings at a fixed ΔHR (R²_average = 0.67-0.78).</p><p><strong>Conclusion: </strong>αTRIMP is a valid and practically accessible method for quantifying internal training exposure using ECG-based HR monitors, which individualises physiological intensity through DFA-α1-derived weightings among individuals of varied fitness exercising at same percentages of HR.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144265696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cold- and hot-water immersion are not more effective than placebo for the recovery of physical performance and training adaptations in national level soccer players.","authors":"Jannik Gustafsson, Diego Montiel-Rojas, Mattias G A Romare, Elin Johansson, Mattias Folkesson, Marco Pernigoni, Anastasija Frolova, Marius Brazaitis, Tomas Venckunas, Elodie Ponsot, Thomas Chaillou, Peter Edholm","doi":"10.1007/s00421-025-05835-w","DOIUrl":"https://doi.org/10.1007/s00421-025-05835-w","url":null,"abstract":"<p><strong>Purpose: </strong>Cold- and hot-water immersion (CWI and HWI, respectively) are popular post-exercise recovery methods in competitive soccer. The aims of this study were to (1) compare the effect of post-exercise CWI, HWI and placebo on the recovery of physical performance in national level soccer players, and (2) investigate whether repeated use of these recovery modalities has an impact on training adaptations over a 15 week period.</p><p><strong>Methods: </strong>For Part I, 40 male soccer players (15-19 years) were randomized to either CWI (10 °C, 10 min), HWI (42 °C, 20 min), or placebo (6 min, sham laser), applied after a 90 min simulated soccer match (SSM). Physical performance was assessed using submaximal aerobic, 20 m sprint, countermovement jump (CMJ), and knee extension strength tests [i.e., maximum voluntary isometric contraction (MVIC) and time to exhaustion (TTE) at 60% of MVIC] performed at Pre-SSM and 0, 21 and 45 h Post-SSM. For Part II, 19 participants applied their respective recovery modality (~ twice a week) in their usual training. After 15 weeks, physical performance and body composition were assessed and compared to pre-intervention.</p><p><strong>Results: </strong>All three modalities similarly affected the recovery of physical performance during the 21-45 h Post-SSM period (p < 0.05). Moreover, no significant effects of the recovery modalities on body composition and on development of physical performance were found over the 15 week recovery intervention (p > 0.05).</p><p><strong>Conclusion: </strong>Compared to a placebo, CWI and HWI do not improve post-match recovery of physical performance and do not impact long-term training adaptations in highly trained soccer players.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144265695","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Individual muscle hypertrophy response is affected by the overload progression model and is associated with changes in satellite cell content.","authors":"Maíra C Scarpelli, João G A Bergamasco, Joshua S Godwin, Paulo H C Mesquita, Talisson S Chaves, Deivid G Silva, Diego Bittencourt, Nathalia F Dias, Ricardo A Medalha Junior, Paulo C Carello Filho, Vitor Angleri, Luiz A R Costa, Andreas N Kavazis, Carlos Ugrinowitsch, Michael D Roberts, Cleiton A Libardi","doi":"10.1007/s00421-025-05817-y","DOIUrl":"https://doi.org/10.1007/s00421-025-05817-y","url":null,"abstract":"<p><strong>Purpose: </strong>We aimed to compare individual hypertrophic responses to resistance training in which overload progressed either by adjusting the load (LOADProg) or by increasing the number of repetitions (REPSProg). Furthermore, we investigated whether greater responsiveness to one protocol was associated with chronic changes in myonuclei and satellite cells, proteolysis and extracellular matrix (ECM) remodeling biomarkers.</p><p><strong>Methods: </strong>Thirty-seven untrained participants had their legs randomized into LOADProg and REPSProg and underwent 10 weeks of training. Muscle cross-sectional area (mCSA) ultrasound and muscle biopsies were performed pre- and post-training. Based on mCSA changes between protocols, we applied a criterion of 2 typical errors (5.7%) to create 4 clusters.</p><p><strong>Results: </strong>Twelve participants (~ 34%) showed greater mCSA increases after REPSProg (14.2 ± 7.6%) than LOADProg (3.4 ± 8.7%, p = 0.004). Seven participants (~ 19%) responded better to LOADProg (21.5 ± 7.5% vs. 12 ± 7.5%, p = 0.041). Thirteen participants (~ 35%) showed no differences between protocols (p = 0.852). Five participants were nonresponders (mCSA changes smaller than the 5.7% threshold) for both protocols. There were no significant differences (p > 0.05) in myonuclear content, proteolysis, or ECM remodeling markers within any of the clusters. However, for those who responded better to REPSProg, this protocol promoted greater satellite cell changes (108.6 ± 77.0%) than LOADProg (48.9 ± 63.1%, p = 0.015).</p><p><strong>Conclusion: </strong>Our findings suggest that overload progression models may influence individual responsiveness to RT-induced muscle hypertrophy. Additionally, progression through increased repetitions was associated with a chronic addition of satellite cells. However, responsiveness was not explained by chronic changes in myonuclei, proteolysis or ECM remodeling biomarkers.</p><p><strong>Trial registration: </strong>This study is registered in the Brazilian Registry of Clinical Trials (RBR-57v9mrb).</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144274537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toward isolating perceptual and physiological contributors to heat sensitivity in multiple sclerosis: insights from a new experimental model.","authors":"Timothy English, Joshua Barton, Nicole Vargas, Michael Barnett, Ollie Jay","doi":"10.1007/s00421-025-05838-7","DOIUrl":"https://doi.org/10.1007/s00421-025-05838-7","url":null,"abstract":"<p><strong>Purpose: </strong>To determine if reductions in whole-body thermal sensation (WBTS) with localised skin cooling mitigate heat-induced visual performance decrements in people with multiple sclerosis (MS), optic neuritis, and heat-sensitive visual symptoms, independent of core temperature increases.</p><p><strong>Methods: </strong>Thirteen participants (7 relapsing-remitting MS (MS) patients with unilateral (left) optic neuritis and heat-sensitive visual symptoms; 6 controls) underwent visual performance testing on each eye at baseline and during passive heating (0.6℃ rise in gastrointestinal temperature (ΔT_GI) via a hot water-perfused suit) under two counterbalanced crossover ordered conditions: 1) cold packs (0℃-CLD) or 2) hot packs (50℃-HOT) applied to the lower back. WBTS, visual symptoms, multifocal visual evoked potentials (mf-VEPs) amplitude/latency, and contrast sensitivity were assessed.</p><p><strong>Results: </strong>ΔT_GI was consistent across trials (p = 0.213; η_p² = 0.21). WBTS was only marginally lower (p = 0.017; η_p² = 0.42) in CLD than HOT for MS (CLD: 5.8 ± 0.9 a.u.; HOT: 6.4 ± 0.7 a.u.) and controls (CLD: 5.0 ± 0.9 a.u.; HOT: 5.9 ± 0.7 a.u.). Passive heating worsened (p = 0.027; η_p² = 0.59) visual symptoms in the affected eye similarly (p = 0.356; η_p² = 0.14) for HOT and CLD conditions. Heating reduced mf-VEPs amplitude in the left (affected) eye (p = 0.007; η_p² = 0.50) similarly (p = 0.332; η_p² = 0.09) across groups and conditions. For the unaffected (right) eye, reductions in mf-VEPs amplitude were greater in MS than controls (p = 0.031; η_p² = 0.36), with no difference between conditions (p = 0.339; η_p² = 0.08). mf-VEPs latency and contrast sensitivity were unaffected by heating.</p><p><strong>Conclusion: </strong>Localised skin cooling during passive heating to a moderate core temperature produces only a modest reduction in WBTS and does not mitigate heat-induced visual performance decrements. The limited perceptual difference achieved suggests the localised skin cooling was insufficient to meaningfully isolate the effects of skin temperature from core temperature.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144274538","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sex differences in the rate of torque development and torque-velocity relationship are due to maximal strength only.","authors":"Francesco Salvaggio, Paolo Riccardo Brustio, Pierre Samozino, Ludovico Grossio, Alberto Rainoldi, Gennaro Boccia","doi":"10.1007/s00421-025-05836-9","DOIUrl":"https://doi.org/10.1007/s00421-025-05836-9","url":null,"abstract":"<p><strong>Purpose: </strong>This study aimed to analyse the sex differences in the rate of torque development (RTD) and torque-velocity parameters with and without normalisation for maximal voluntary torque (MVT).</p><p><strong>Methods: </strong>Right-leg knee extensors were tested in 64 healthy and active participants (31 F and 33 M). MVT and RTD were obtained under isometric conditions. Individual torque-velocity relationships were obtained using a curvilinear model on averaged torque and velocity over 80°-to-140° knee angle. Dynamic data were acquired through an incremental protocol on a leg extension machine, going from the lightest to the unmovable load despite maximal effort.</p><p><strong>Results: </strong>Independent samples t test revealed (p < 0.001) that males possess greater RTD measured at 50 ms (d = -1.2), 100ms (d = -2.1) and 150ms (d = -2.3), peak RTD (d = -1.3) and MVT (d = 2.1). When normalised by MVT, the sex differences in RTD disappeared. Curvilinear hyperbolic TV relationship well-fitted (R² = 0.99). In FV parameters, maximal theoretical torque (d = -1.7), maximal power (P_max) (d = -2.0), and torque at P_max (d = -1.7) were greater in males (p < .05), while maximal theoretical velocity (V₀) and velocity at P_max did not differ.</p><p><strong>Conclusions: </strong>The sex differences in explosiveness (i.e., rapid isometric and dynamic force production) were mainly due to greater maximal strength in males than in females. These findings suggest that, in non-sedentary people, males do not present higher contraction velocity capacities, i.e. higher maximal velocity until which muscles can produce force, than females in knee extension.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144257704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reticulospinal and corticospinal responses in long-term strength-trained and untrained adults.","authors":"Meghan Tanel, Dawson J Kidgell, Sakari Vekki, Juha P Ahtiainen, Gonzalo Gomez-Guerrero, Eeli J Halonen, Stuart N Baker, Simon Walker","doi":"10.1007/s00421-025-05834-x","DOIUrl":"https://doi.org/10.1007/s00421-025-05834-x","url":null,"abstract":"<p><strong>Purpose: </strong>Studies investigating neural adaptation to strength training have yet to determine the loci of previously observed improvements in motor pathway function. While transcranial magnetic stimulation (TMS) studies have typically focused on the corticospinal tract, recent evidence from primates suggests that the subcortical reticulospinal tract may be the primary candidate for adaptation.</p><p><strong>Methods: </strong>Using a cross-sectional comparison, long-term strength-trained athletes (n = 15, 11M/4F, 32 ± 6 y) and untrained adults (n = 18, 11M/7F, 32 ± 4 y) underwent a series of neurophysiological tests designed to target corticospinal and reticulospinal functioning based on biceps brachii muscle responses. The StartReact test was used to determine reaction time, rate of torque development, and muscle activity in response to visual (V), visual-auditory (VA, 80 dB), and visual-startle (VS, 120 dB) cues. Reaction times were used to calculate reticulospinal gain ([V-VS]/[V-VA]). Neuro-navigated monophasic TMS to the motor cortex was given during low-force level isometric voluntary contractions (10% of maximum) with both posterior-anterior (100-180% active motor threshold) and anterior-posterior currents (120% active motor threshold). Motor evoked potentials (MEPs) from stimuli given at 120% active motor threshold were compared to startle cue-conditioned responses and anterior-posterior current responses.</p><p><strong>Results: </strong>Untrained adults benefitted more from StartReact (reticulospinal gain, p = 0.003), whereas strength-trained athletes showed greater MEP size at higher stimulation intensities (180% active motor threshold, p = 0.048, 140-180% area-under-the-curve, p = 0.020) and shorter silent period (180% active motor threshold, p = 0.035).</p><p><strong>Conclusions: </strong>Evidence provided here suggests greater cortico-reticulospinal excitability/functioning in long-term strength-trained athletes.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144257703","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}