European Journal of Applied Physiology最新文献

{"title":"Sex differences in thermophysiological responses of elderly to low-intensity exercise during uncompensable heat strain.","authors":"Hein A M Daanen, Iris Dijkstra, Emma Abbink, Iris J de Jong, S Tony Wolf, Coen C W G Bongers, Laurens S Hondema, Thijs M H Eijsvogels, Boris R M Kingma","doi":"10.1007/s00421-024-05457-8","DOIUrl":"10.1007/s00421-024-05457-8","url":null,"abstract":"<p><strong>Purpose: </strong>The rising frequency of extreme heat events poses an escalating threat of heat-related illnesses and fatalities, placing an additional strain on global healthcare systems. Whether the risk of heat-related issues is sex specific, particularly among the elderly, remains uncertain.</p><p><strong>Methods: </strong>16 men and 15 women of similar age (69 ± 5 years) were exposed to an air temperature of 39.1 ± 0.3 °C and a relative humidity (RH) of 25.1 ± 1.9%, during 20 min of seated rest and at least 40 min of low-intensity (10 W) cycling exercise. RH was gradually increased by 2% every 5 min starting at minute 30. We measured sweat rate, heart rate, thermal sensation, and the rise in gastrointestinal temperature (Tgi) and skin temperature (Tsk).</p><p><strong>Results: </strong>Tgi consistently increased from minute 30 to 60, with no significant difference between females and males (0.012 ± 0.004 °C/min vs. 0.011 ± 0.005 °C/min; p = 0.64). Similarly, Tsk increase did not differ between females and males (0.044 ± 0.007 °C/min vs. 0.038 ± 0.011 °C/min; p = 0.07). Females exhibited lower sweat rates than males (0.29 ± 0.06 vs. 0.45 ± 0.14 mg/m²/min; p < 0.001) in particular at relative humidities exceeding 30%. No sex differences in heart rate and thermal sensation were observed.</p><p><strong>Conclusion: </strong>Elderly females exhibit significantly lower sweat rates than their male counterparts during low-intensity exercise at ambient temperatures of 39 °C when humidity exceeds 30%. However, both elderly males and females demonstrate a comparable rise in core temperature, skin temperature, and mean body temperature, indicating similar health-related risks associated with heat exposure.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11322401/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140318055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GH and IGF-1 in skin interstitial fluid and blood are associated with heat loss responses in exercising young adults.","authors":"Gulinu Maimaituxun, Tatsuro Amano, Glen P Kenny, Toby Mündel, Masanobu Kajiki, Kaname Tagawa, Akira Katagiri, Yoko Tanabe, Koichi Watanabe, Takeshi Nishiyasu, Narihiko Kondo, Naoto Fujii","doi":"10.1007/s00421-024-05448-9","DOIUrl":"10.1007/s00421-024-05448-9","url":null,"abstract":"<p><strong>Purpose: </strong>Sweat glands and cutaneous vessels possess growth hormone (GH) and insulin-like growth factor 1 (IGF-1) receptors. Here, we assessed if exercise increases GH and IGF-1 in skin interstitial fluid, and whether baseline and exercise-induced increases in GH and IGF-1 concentrations in skin interstitial fluid/blood are associated with heat loss responses of sweating and cutaneous vasodilation.</p><p><strong>Methods: </strong>Sixteen young adults (7 women) performed a 50-min moderate-intensity exercise bout (50% VO_2peak) during which skin dialysate and blood samples were collected. In a sub-study (n = 7, 4 women), we administered varying concentrations of GH (0.025-4000 ng/mL) and IGF-1 (0.000256-100 µg/mL) into skin interstitial fluid via intradermal microdialysis. Sweat rate (ventilated capsule) and cutaneous vascular conductance (CVC) were measured continuously for both studies.</p><p><strong>Results: </strong>Exercise increased sweating and CVC (both P < 0.001), paralleled by increases of serum GH and skin dialysate GH and IGF-1 (all P ≤ 0.041) without changes in serum IGF-1. Sweating was positively correlated with baseline dialysate and serum GH levels, as well as exercise-induced increases in serum GH and IGF-1 (all P ≤ 0.044). Increases in CVC were not correlated with any GH and IGF-1 variables. Exogenous administration of GH and IGF-1 did not modulate resting sweat rate and CVC.</p><p><strong>Conclusion: </strong>(1) Exercise increases GH and IGF-1 levels in the skin interstitial fluid, (2) exercise-induced sweating is associated with baseline GH in skin interstitial fluid and blood, as well as exercise-induced increases in blood GH and IGF-1, and (3) cutaneous vasodilation during exercise is not associated with GH and IGF-1 in skin interstitial fluid and blood.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140039004","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 effect of sodium bicarbonate mini-tablets ingested in a carbohydrate hydrogel system on 40 km cycling time trial performance and metabolism in trained male cyclists","authors":"Eli Spencer Shannon, Amanda Regnier, Ben Dobson, Xiaolin Yang, S. Andy Sparks, Lars Robert Mc Naughton","doi":"10.1007/s00421-024-05567-3","DOIUrl":"https://doi.org/10.1007/s00421-024-05567-3","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Introduction</h3><p>Sodium bicarbonate (NaHCO₃) ingestion has been found to be ergogenic in high-intensity exercise that ranges from 1 to 10 min; however, limited studies have investigated high-intensity exercise beyond this duration.</p><h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>The present study aimed to determine the effect of NaHCO₃ ingested using a carbohydrate hydrogel delivery system on 40 km time trial (TT) performance in trained male cyclists.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>Fourteen trained male cyclists ingested 0.3 g kg⁻¹ BM NaHCO₃ (Maurten AB, Sweden) to determine individualised peak alkalosis, which established time of ingestion prior to exercise. Participants completed a 40 km familiarisation TT, and two 40 km experimental TTs after ingestion of either NaHCO₃ or placebo in a randomised, double-blind, crossover design.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>NaHCO₃ supplementation improved performance (mean improvement = 54.14 s ± 18.16 s; <i>p</i> = 0.002, <i>g</i> = 0.22) and increased blood buffering capacity prior to (HCO₃⁻ mean increase = 5.6 ± 0.2 mmol L⁻¹, <i>p</i> &lt; 0.001) and throughout exercise (<i>f</i> = 84.82, <i>p</i> &lt; 0.001, pη² = 0.87) compared to placebo. There were no differences in total gastrointestinal symptoms (GIS) between conditions either pre- (NaHCO₃, 22 AU; Placebo, 44 AU; <i>p</i> = 0.088, <i>r</i> = 0.46) or post-exercise (NaHCO₃, 76 AU; Placebo, 63 AU; <i>p</i> = 0.606, <i>r</i> = 0.14).</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>The present study suggests that ingesting NaHCO₃ mini-tablets in a carbohydrate hydrogel can enhance 40 km TT performance in trained male cyclists, with minimal GIS. This ingestion strategy could therefore be considered by cyclists looking for a performance enhancing ergogenic aid.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141771290","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":"Mechanical efficiency: associations with body composition and glycemic profile in healthy adults.","authors":"Elisa Marin-Couture, Louis Pérusse, Claude Bouchard, Patrick Schrauwen, Denis R Joanisse, Angelo Tremblay","doi":"10.1007/s00421-024-05528-w","DOIUrl":"https://doi.org/10.1007/s00421-024-05528-w","url":null,"abstract":"<p><p>The aim of this study was to assess the association between net mechanical efficiency (NME) and body composition and glycemic profile, in middle-aged (38.3 ± 14.3 years) participants from the Quebec Family Study (QFS). Analyses were completed on a sample of 605 participants (271 males and 334 females) who performed a submaximal exercise test on an ergometer consisting of three consecutive 6-min workloads at increasing intensity during which respiratory gas exchange was assessed. The calculation of NME [power output/ (vO₂-vO₂seated before exercise)] was based on the values of the last 3 min of the first workload at a targeted power output of 30 W. Correlations between NME and dependent variables were computed separately in males and females. Associations between NME and body composition and glucose-insulin variables were assessed by comparing groups of subjects categorized in sex-specific tertiles of NME after adjustments for age. Significant negative correlations were observed between NME and body composition and glycemic profile in both sexes. Comparison across tertiles showed that individuals with high NME displayed more favorable adiposity and glycemic profiles. These differences remained significant after further adjustments for participation in vigorous physical activity, cardiorespiratory fitness, and mean exercise respiratory exchange ratio whereas most differences in glucose-insulin variables became non-significant after further adjustment for percent body fat. QFS familial data indicate that the heritability of NME reaches about 30%. In conclusion, the results of this study show that beyond aerobic fitness and physical activity-participation, mechanical efficiency is an additional activity-related variable that is independently associated with variations in body composition and glycemic profile.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141787699","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":"Critical evaluation and recalculation of current systematic reviews with meta-analysis on the effects of acute and chronic stretching on passive properties and passive peak torque","authors":"Konstantin Warneke, Lars Hubertus Lohmann, Gerit Plöschberger, Andreas Konrad","doi":"10.1007/s00421-024-05564-6","DOIUrl":"https://doi.org/10.1007/s00421-024-05564-6","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Purpose</h3><p>Muscle, tendon, and muscle–tendon unit (MTU) stiffness as well as passive peak torque (PPT) or delayed stretching pain sensation are typical explanatory approaches for stretching adaptations. However, in literature, differences in the study inclusion, as well as applying meta-analytical models without accounting for intrastudy dependency of multiple and heteroscedasticity of data bias the current evidence. Furthermore, most of the recent analyses neglected to investigate PPT adaptations and further moderators.</p><h3 data-test=\"abstract-sub-heading\">Methods</h3><p>The presented review used the recommended meta-analytical calculation method to investigate the effects of stretching on stiffness as well as on passive torque parameters using subgroup analyses for stretching types, stretching duration, and supervision.</p><h3 data-test=\"abstract-sub-heading\">Results</h3><p>Chronic stretching reduced muscle stiffness ( − 0.38, <i>p</i> = 0.01) overall, and also for the supervised ( − 0.49, <i>p</i> = 0.004) and long static stretching interventions ( − 0.61, <i>p</i> &lt; 0.001), while the unsupervised and short duration subgroups did not reach the level of significance (<i>p</i> = 0.21, 0.29). No effects were observed for tendon stiffness or for subgroups (e.g., long-stretching durations). Chronic PPT (0.55, <i>p</i> = 0.005) in end ROM increased. Only long-stretching durations sufficiently decreased muscle stiffness acutely. No effects could be observed for acute PPT.</p><h3 data-test=\"abstract-sub-heading\">Conclusion</h3><p>While partially in accordance with previous literature, the results underline the relevance of long-stretching durations when inducing changes in passive properties. Only four acute PPT in end ROM studies were eligible, while a large number were excluded as they provided mathematical models and/or lacked control conditions, calling for further randomized controlled trials on acute PPT effects.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":3.0,"publicationDate":"2024-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141785028","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 effect of a 4-week, remotely administered, post-exercise passive leg heating intervention on determinants of endurance performance.","authors":"Kevin John, Joe Page, Shane M Heffernan, Gillian E Conway, Neil E Bezodis, Liam P Kilduff, Brad Clark, Julien D Périard, Mark Waldron","doi":"10.1007/s00421-024-05558-4","DOIUrl":"https://doi.org/10.1007/s00421-024-05558-4","url":null,"abstract":"<p><strong>Purpose: </strong>Post-exercise passive heating has been reported to augment adaptations associated with endurance training. The current study evaluated the effect of a 4-week remotely administered, post-exercise passive leg heating protocol, using an electrically heated layering ensemble, on determinants of endurance performance.</p><p><strong>Methods: </strong>Thirty recreationally trained participants were randomly allocated to either a post-exercise passive leg heating (PAH, n = 16) or unsupervised training only control group (CON, n = 14). The PAH group wore the passive heating ensemble for 90-120 min/day, completing a total of 20 (16 post-exercise and 4 stand-alone leg heating) sessions across 4 weeks. Whole-body (peak oxygen uptake, gas exchange threshold, gross efficiency and pulmonary oxygen uptake kinetics), single-leg exercise (critical torque and NIRS-derived muscle oxygenation), resting vascular characteristics (flow-mediated dilation) and angiogenic blood measures (nitrate, vascular endothelial growth factor and hypoxia inducible factor 1-α) were recorded to characterize the endurance phenotype. All measures were assessed before (PRE), at 2 weeks (MID) and after (POST) the intervention.</p><p><strong>Results: </strong>There was no effect of the intervention on test of whole-body endurance capacity, vascular function or blood markers (p > 0.05). However, oxygen kinetics were adversely affected by PAH, denoted by a slowing of the phase II time constant; τ (p = 0.02). Furthermore, critical torque-deoxygenation ratio was improved in CON relative to PAH (p = 0.03).</p><p><strong>Conclusion: </strong>We have demonstrated that PAH had no ergogenic benefit but instead elicited some unfavourable effects on sub-maximal exercise characteristics in recreationally trained individuals.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141757933","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":"Metabolic flexibility and resting autonomic function in active menopausal women.","authors":"Jordi Monferrer-Marín, Ainoa Roldán, Jørn Wulff Helge, Cristina Blasco-Lafarga","doi":"10.1007/s00421-024-05568-2","DOIUrl":"https://doi.org/10.1007/s00421-024-05568-2","url":null,"abstract":"<p><strong>Purpose: </strong>The present study aims to analyze the relationship between cardiac autonomic control at rest-i.e., baseline Heart Rate Variability (HRV)-and metabolic flexibility assessed by means of the FATox and CHOox oxidation rates at the intensities of maximum fat and carbohydrate oxidation (MFO and MCO, respectively).</p><p><strong>Methods: </strong>Twenty-four active over-60 women (66.8 ± 4.4 years) had their HRV assessed with 10 min recordings under resting conditions, and this was analyzed with Kubios Scientific software. After this, an incremental submaximal cycling test, starting at 30 watts, with increments of 10 watts every 3 min 15 s was performed. FATox and CHOox were calculated in the last 60 s at each step, using Frayn's equation. MFO and MCO were further obtained.</p><p><strong>Results: </strong>Nonlinear SampEn and 1-DFAα1 (Detrending Fluctuation Analysis score) at rest were both moderate and significantly (p < 0.05) related to FATox (r = 0.43, r = -0.40) and CHOox (r = -0.59, r = 0.41), as well as RER (r = -0.43, r = 0.43) at FATmax intensity. At the MCO intensity, no association was observed between HRV and oxidation rates. However, DFAα1 (r = -0.63, p < 0.05), the frequency ratio LF/HF (r = -0.63, p < 0.05), and the Poincaré ratio SD1/SD2 (r = 0.48, p < 0.05) were correlated with blood lactate concentration.</p><p><strong>Conclusion: </strong>These results support the autonomic resources hypothesis, suggesting that better autonomic function at rest is related to enhanced metabolic flexibility in postmenopausal women. They also underpin a comprehensive analysis of cardiovascular-autonomic health with aging. The results imply that non-linear DFAα1 and SampEn are appropriate to analyze this association in health of the aging cardiovascular-autonomic system.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141757931","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":"Testing the predictive capacity of a muscle fatigue model on electrically stimulated adductor pollicis.","authors":"M Vonderscher, M Bowen, P Samozino, B Morel","doi":"10.1007/s00421-024-05551-x","DOIUrl":"https://doi.org/10.1007/s00421-024-05551-x","url":null,"abstract":"<p><strong>Purpose: </strong>Based on the critical power (P_c or critical force; F_c) concept, a recent mathematical model formalised the proportional link between the decrease in maximal capacities during fatiguing exercises and the amount of impulse accumulated above F_c. This study aimed to provide experimental support to this mathematical model of muscle fatigability in the severe domain through testing (i) the model identifiability using non-exhausting tests and (ii) the model ability to predict time to exhaustion (t_lim) and maximal force (F_max) decrease.</p><p><strong>Methods: </strong>The model was tested on eight participants using electrically stimulated adductor pollicis muscle force. The F_max was recorded every 15 s for all tests, including five constant tests to estimate the initial maximal force (F_i), F_c, and a time constant (τ). The model's parameters were used to compare the predicted and observed t_lim values of the incremental ramp test and F_max(t) of the sine test.</p><p><strong>Results: </strong>The results showed that the model accurately estimated F_i, F_c, and τ (CI95% = 2.7%Fi and 9.1 s for F_c and τ, respectively; median adjusted r² = 0.96) and predicted t_lim and F_max with low systematic and random errors (11 ± 20% and - 1.8 ± 7.7%F_i, respectively).</p><p><strong>Conclusion: </strong>This study revealed the potential applications of a novel mathematical formalisation that encompasses previous research on the critical power concept. The results indicated that the model's parameters can be determined from non-exhaustive tests, as long as maximal capacities are regularly assessed. With these parameters, the evolution of maximal capacities (i.e. fatigability) at any point during a known exercise and the time to exhaustion can be accurately predicted.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141757932","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":"A single, maximal dose of celecoxib, ibuprofen, or flurbiprofen does not reduce the muscle signalling response to plyometric exercise in young healthy adults.","authors":"Brandon M Roberts, Alyssa V Geddis, Cara E Sczuroski, Marinaliz Reynoso, Julie M Hughes, Jess A Gwin, Jeffery S Staab","doi":"10.1007/s00421-024-05565-5","DOIUrl":"https://doi.org/10.1007/s00421-024-05565-5","url":null,"abstract":"<p><strong>Background: </strong>Non-steroidal anti-inflammatory drugs (NSAIDs) possess analgesic and anti-inflammatory properties by inhibiting cyclooxygenase (COX) enzymes. Conflicting evidence exists on whether NSAIDs influence signaling related to muscle adaptations and exercise with some research finding a reduction in muscle protein synthesis signaling via the AKT-mTOR pathway, changes in satellite cell signaling, reductions in muscle protein degradation, and reductions in cell proliferation. In this study, we determined if a single maximal dose of flurbiprofen (FLU), celecoxib (CEL), ibuprofen (IBU), or a placebo (PLA) affects the short-term muscle signaling responses to plyometric exercise.</p><p><strong>Methods: </strong>This was a block randomized, double-masked, crossover design, where 12 participants performed four plyometric exercise bouts consisting of 10 sets of 10 plyometric jumps at 40% 1RM. Two hours before exercise, participants consumed a single dose of celecoxib (CEL 200 mg), IBU (800 mg), FLU (100 mg) or PLA with food. Muscle biopsy samples were collected before and 3-h after exercise from the vastus lateralis. Data were analyzed using a repeated measures (RM) ANOVA, ANOVA, or a Friedman test. Significance was considered at p < 0.05.</p><p><strong>Results: </strong>We found no treatment effects on the mRNA expression of PTSG1, PTSG2, MYC, TBP, RPLOP, MYOD1, Pax7, MYOG, Atrogin-1, or MURF1 (all, p > 0.05). We also found no treatment effects on AKT-mTOR signaling or MAPK signaling measured through the phosphorylation status of mTORS2441, mTORS2448, RPS6 235/236, RPS 240/244, 4EBP1, ERK1/2, p38 T180/182 normalized to their respective total abundance (all, p > 0.05). However, we did find a significant difference between MNK1 T197/202 in PLA compared to FLU (p < .05).</p><p><strong>Conclusion: </strong>A single, maximal dose of IBU, CEL, or FLU taken prior to exercise did not affect the signaling of muscle protein synthesis, protein degradation, or ribosome biogenesis three hours after a plyometric training bout.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141751415","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":"Reduced rate of force development under fatigued conditions is associated to the decline in force complexity in adult males.","authors":"Samuel D'Emanuele, Gennaro Boccia, Luca Angius, Oliver Hayman, Stuart Goodall, Federico Schena, Cantor Tarperi","doi":"10.1007/s00421-024-05561-9","DOIUrl":"https://doi.org/10.1007/s00421-024-05561-9","url":null,"abstract":"<p><strong>Purpose: </strong>This study aimed to verify whether the slowing of muscle contraction quickness, typically observed in states of fatigue, may worsen force control by decreasing the rate with which force fluctuations are modulated. Therefore, we investigated the relationship between rate of force development (RFD), and force fluctuations' magnitude (Coefficient of variation, CoV) and complexity (Approximate Entropy, ApEn; Detrended fluctuation analysis, DFAα).</p><p><strong>Methods: </strong>Fourteen participants performed intermittent ballistic isometric contractions of the plantar dorsiflexors at 70% of maximal voluntary force until task failure (under 60% twice).</p><p><strong>Results: </strong>Indices of RFD (RFD_peak, RFD₅₀, RFD₁₀₀, and RFD₁₅₀) decreased over time by approximately 46, 32, 44, and 39%, respectively (p all ≤ 0.007). DFAα increased by 10% (p < 0.001), and CoV increased by 15% (p < 0.001), indicating decreased force complexity along with increased force fluctuations, respectively. ApEn decreased by just over a quarter (28%, p < 0.001). The linear hierarchical models showed negative associations between RFD_peak and DFAα (β =  - 3.6 10^-4, p < 0.001), CoV (β =  - 1.8 10^-3, p < 0.001), while ApEn showed a positive association (β = 8.2 × 10^-5, p < 0.001).</p><p><strong>Conclusion: </strong>The results suggest that exercise-induced reductions in contraction speed, lead to smoother force complexity and diminished force control due to slower adjustments around the target force. The fatigued state resulted in worsened force producing capacity and overall force control.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":null,"pages":null},"PeriodicalIF":2.8,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141751417","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}