European Journal of Applied Physiology最新文献

{"title":"Alterations in magnitude and spatial distribution of erector spinae muscle activity in cyclists with a recent history of low back pain.","authors":"Alessandro Sampieri, Giuseppe Marcolin, Federico Gennaro, Emanuele Magistrelli, Alessandro Del Vecchio, Tatiana Moro, Antonio Paoli, Andrea Casolo","doi":"10.1007/s00421-024-05628-7","DOIUrl":"10.1007/s00421-024-05628-7","url":null,"abstract":"<p><strong>Purpose: </strong>While cycling offers several health benefits, repetitive loading and maintenance of static postures for prolonged periods expose cyclists to low back pain (LBP). Despite high LBP prevalence in cyclists, underlying pathomechanics and specific lumbar region muscle activation patterns during cycling are unclear. Here, we compared lumbar erector spinae (ES) muscles activation and spatial distribution activity in cyclists with and without recent LBP history.</p><p><strong>Methods: </strong>Ten cyclists with recent LBP history (LBPG; Oswestry Disability Index score ~ 17.8%) and 11 healthy cyclists (CG) were recruited. After assessing the Functional Threshold Power (FTP), participants underwent an incremental cycling test with 4 × 3 min steps at 70%, 80%, 90%, and 100% of their FTP. High-density surface electromyography (HDsEMG) signals were recorded from both lumbar ES using two 64-channel grids. Information about ES activation levels (root-mean-square, RMS), degree of homogeneity (entropy), and cranio-caudal displacement of muscle activity (Y-axis coordinate of the barycenter of RMS maps) was extracted from each grid separately and then grand-averaged across both grids.</p><p><strong>Results: </strong>Repeated-measure 2-way ANOVAs showed a significant intensity by group interaction for RMS amplitude (p = 0.003), entropy (p = 0.038), and Y-bar displacement (p = 0.033). LBPG increased RMS amplitude between 70-100% (+ 19%, p = 0.010) and 80-100% FTP (+ 21%, p = 0.004) and decreased entropy between 70-100% FTP (- 8.4%, p = 0.003) and 80-100% FTP (- 8.5%, p = 0.002). Between-group differences emerged only at 100% FTP (+ 9.6%, p = 0.049) for RMS amplitude.</p><p><strong>Conclusion: </strong>Our findings suggest that cyclists with recent LBP history exhibit higher ES muscles activation and less homogeneous activity compared to healthy controls, suggesting potential inefficient muscle recruitment strategy.</p><p><strong>Trial registration number: </strong>HEC-DSB/09-2023.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"967-976"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950058/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142371360","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":"Enhancing endurance performance predictions: the role of movement velocity in metabolic simulations demonstrated by cycling cadence.","authors":"Anna Katharina Dunst, Clemens Hesse, Olaf Ueberschär","doi":"10.1007/s00421-024-05663-4","DOIUrl":"10.1007/s00421-024-05663-4","url":null,"abstract":"&lt;p&gt;&lt;strong&gt;Background: &lt;/strong&gt;Mader's mathematical model, widely employed for endurance performance prediction, aims to accurately represent metabolic response to exercise. However, it traditionally overlooks dynamic changes in metabolic processes at varying movement velocities.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;This narrative review examined the effect of cycling cadence on its key input parameters, including oxygen demand per Watt ( &lt;math&gt;&lt;msub&gt;&lt;mtext&gt;CE&lt;/mtext&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;mtext&gt;O2&lt;/mtext&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; ), resting oxygen uptake ( &lt;math&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;msub&gt;&lt;mtext&gt;O&lt;/mtext&gt; &lt;mtext&gt;2Base&lt;/mtext&gt;&lt;/msub&gt; &lt;/mrow&gt; &lt;/math&gt; ), maximal oxygen uptake ( &lt;math&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;msub&gt;&lt;mtext&gt;O&lt;/mtext&gt; &lt;mtext&gt;2max&lt;/mtext&gt;&lt;/msub&gt; &lt;/mrow&gt; &lt;/math&gt; ), and maximal blood lactate accumulation rate (vLa&lt;sub&gt;max&lt;/sub&gt;). These findings were integrated into the model to assess cadence-induced variations in predicted power output at maximal aerobic power (MAP), maximal lactate steady state (MLSS), and peak fat oxidation (FAT&lt;sub&gt;max&lt;/sub&gt;).&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;A U-shaped relationship was found between cadence and both &lt;math&gt;&lt;msub&gt;&lt;mtext&gt;CE&lt;/mtext&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;mtext&gt;O2&lt;/mtext&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; and &lt;math&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;msub&gt;&lt;mtext&gt;O&lt;/mtext&gt; &lt;mtext&gt;2Base&lt;/mtext&gt;&lt;/msub&gt; &lt;/mrow&gt; &lt;/math&gt; , while &lt;math&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;msub&gt;&lt;mtext&gt;O&lt;/mtext&gt; &lt;mtext&gt;2max&lt;/mtext&gt;&lt;/msub&gt; &lt;/mrow&gt; &lt;/math&gt; remained largely cadence-independent within typical cadences. vLa&lt;sub&gt;max&lt;/sub&gt; exhibited a polynomial increase with cadence, attributed to changes in lactate elimination, suggesting cadence-independent maximal glycolytic flux. Incorporating these findings into Mader's model considering various scenarios revealed significant cadence-induced variations, with power output differences of up to &gt; 100 W. Using cadence-dependent &lt;math&gt;&lt;msub&gt;&lt;mtext&gt;CE&lt;/mtext&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;mtext&gt;O2&lt;/mtext&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;/math&gt; and &lt;math&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;msub&gt;&lt;mtext&gt;O&lt;/mtext&gt; &lt;mtext&gt;2Base&lt;/mtext&gt;&lt;/msub&gt; &lt;/mrow&gt; &lt;/math&gt; while maintaining constant &lt;math&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;msub&gt;&lt;mtext&gt;O&lt;/mtext&gt; &lt;mtext&gt;2max&lt;/mtext&gt;&lt;/msub&gt; &lt;/mrow&gt; &lt;/math&gt; and vLa&lt;sub&gt;max&lt;/sub&gt; yielded polynomial power output-cadence relationships, with optimal cadences of 84 rpm at MAP, 80 rpm at MLSS, and 70 rpm at FAT&lt;sub&gt;max&lt;/sub&gt;. Incorporating cadence-dependent vLa&lt;sub&gt;max&lt;/sub&gt; produced implausible results, supporting cadence-independent maximal glycolytic flux. A hypothesized cadence-dependent &lt;math&gt; &lt;mrow&gt;&lt;mover&gt;&lt;mtext&gt;V&lt;/mtext&gt; &lt;mo&gt;˙&lt;/mo&gt;&lt;/mover&gt; &lt;msub&gt;&lt;mtext&gt;O&lt;/mtext&gt; &lt;mtext&gt;2max&lt;/mtext&gt;&lt;/msub&gt; &lt;/mrow&gt; &lt;/math&gt; improved alignment between model predictions and empirical data.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;Negl","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"895-907"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950142/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143188867","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":"Neuromuscular fatigability is not affected by the contraction pattern of exercises with a similar mean torque.","authors":"Loïc Lebesque, Gil Scaglioni, Patrick Manckoundia, Alain Martin","doi":"10.1007/s00421-024-05660-7","DOIUrl":"10.1007/s00421-024-05660-7","url":null,"abstract":"<p><strong>Purpose: </strong>Neuromuscular fatigability is task-dependent, but the influence of the contraction pattern on neuromuscular fatigability is largely unknown. Therefore, the present study aims to investigate if neuromuscular fatigability is affected by the contraction pattern of exhausting isometric exercises.</p><p><strong>Methods: </strong>Thirteen participants sustained a plantar flexors MVC for 1 min (MVC_1-MIN) before and after exhausting exercises designed to produce a similar mean torque (30% MVC), and following a 10-min rest period. Exercises consisted of intermittent (INT), continuous (CON) or variable (continuous contraction alternating between moderate and low intensity, VAR) contractions performed until task failure.</p><p><strong>Results: </strong>The INT resulted in greater exercise duration and torque-time integral than CON and VAR. MVC similarly decreased after all exercises due to neural and muscular impairments. The torque loss during the MVC_1-MIN increased after all exercises to a similar extent, mainly because of neural alterations. Contrary to MVC, the torque loss during the MVC_1-MIN returned to baseline value after the recovery period.</p><p><strong>Conclusion: </strong>INT, CON and VAR exercises, performed with identical mean torque and until exhaustion, led to a similar neuromuscular fatigability. When the mean torque is matched among exercises, the contraction pattern does not influence the extent of neuromuscular fatigability, assessed through the maximal torque production and sustainability. The present findings are crucial to consider for the management of neuromuscular fatigability in physical conditioning in both athletes and patients.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1115-1127"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142715611","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":"Vigorous intensity heart rate-clamp exercise does not elicit recommended oxygen consumption rates.","authors":"Clara J Mitchinson, Djadmann Gustave, Pasquale J Succi, Brian Benitez, Minyoung Kwak, Haley C Bergstrom","doi":"10.1007/s00421-024-05665-2","DOIUrl":"10.1007/s00421-024-05665-2","url":null,"abstract":"<p><strong>Purpose: </strong>This study examined the power output adjustments and subsequent shifts in metabolic (V̇O₂) demands as well as minute ventilation ( <math> <msub><mover><mtext>V</mtext> <mo>˙</mo></mover> <mtext>E</mtext></msub> </math> ), respiratory rate (RR), and rating of perceived exertion (RPE) responses during vigorous intensity (77-95% HR_peak) heart rate (HR)-clamp cycle ergometry.</p><p><strong>Methods: </strong>Fifteen males (mean ± SD age = 25.9 ± 4.4 years) performed a graded exercise test to exhaustion to determine peak parameters and three, randomly ordered, HR-clamp trials to exhaustion, up to 60 min, at the lower (HR_L = 77% HR_peak), middle (HR_M = 86% HR_peak), and higher (HR_H = 95% HR_peak) end of the vigorous intensity range. Time course of changes were examined.</p><p><strong>Results: </strong>The times to exhaustion (T_lim) for the HR_L, HR_M, and HR_H trials were 56.05 ± 10.09, 44.22 ± 19.00, and 9.74 ± 7.54 min, respectively. There were significant decreases in power output, <math> <msub> <mrow><mover><mtext>V</mtext> <mo>˙</mo></mover> <mtext>O</mtext></mrow> <mn>2</mn></msub> </math> , and <math> <msub><mover><mtext>V</mtext> <mo>˙</mo></mover> <mtext>E</mtext></msub> </math> across time for each trial, but no changes in RR, and increases in RPE (p < 0.05). Responses were intensity specific for all variables such that mean values were lower for HR_L than HR_M, and HR_L and HR_M were lower than HR_H. The mean <math> <msub> <mrow><mover><mtext>V</mtext> <mo>˙</mo></mover> <mtext>O</mtext></mrow> <mn>2</mn></msub> </math> (HR_L = 56.7 ± 3.8, HR_M = 68.1 ± 4.3, and HR_H = 90.5 ± 3.3% <math> <msub> <mrow><mover><mtext>V</mtext> <mo>˙</mo></mover> <mtext>O</mtext></mrow> <mtext>2max</mtext></msub> </math> ) responses fell below the recommended <math> <msub> <mrow><mover><mtext>V</mtext> <mo>˙</mo></mover> <mtext>O</mtext></mrow> <mn>2</mn></msub> </math> range for vigorous exercise at 10%T_lim for HR_L, and at 90%T_lim for HR_M, but remained above the recommended V̇O₂ range for vigorous exercise until 70% of T_lim for HR_H.</p><p><strong>Conclusions: </strong>Only the HR_M trial met the current guidelines of a vigorous intensity <math> <msub> <mrow><mover><mtext>V</mtext> <mo>˙</mo></mover> <mtext>O</mtext></mrow> <mn>2</mn></msub> </math> sustained for at least 20 min. This study indicated that HR-clamp exercise cannot be consistently used to prescribe a desired metabolic stimulus for exercise performed in a single session.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1205-1218"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142767013","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 impact of skinfold thickness and exercise intensity on the reliability of NIRS in the vastus lateralis.","authors":"Lena Stuer, Massimo Teso, Alessandro L Colosio, Maura Loi, Patrick Mucci, Silvia Pogliaghi, Jan Boone, Kevin Caen","doi":"10.1007/s00421-024-05654-5","DOIUrl":"10.1007/s00421-024-05654-5","url":null,"abstract":"<p><strong>Purpose: </strong>The aims of this study were (1) to assess the test-retest reliability of the primary near infrared spectroscopy (NIRS) variables (i.e., StO₂, T[Hb], [HbO₂] and [HHb]) during cycling and (2) to investigate potential influences of exercise intensity and adipose tissue thickness (ATT) on this reliability.</p><p><strong>Methods: </strong>21 men and 20 women completed twelve constant work rate tests (6 min) at six different exercise intensities with each intensity performed twice. NIRS variables were measured at the vastus lateralis. The coefficient of variance (CV%), the intraclass correlation coefficient (ICC), mean bias and limits of agreement (LoA) were determined for reliability purposes.</p><p><strong>Results: </strong>The reliability of baseline values were acceptable to very good (CV% range: 5.83 - 21.96%). The reliability of end-values (CV% range: 0.02 - 25.02%, ICC range: 0.0 - 0.935) and amplitudes (CV% range: 0.46 - 5099%, ICC range: 0.0 - 0.887) were more variable. In general, the mean biases of end-values and amplitudes showed wide limits of agreement. A homogeneous influence of exercise intensity on reliability could not be established but reliability measures appeared to be lower in people with a lower skinfold thickness. Moreover, the NIRS signals decreased with increasing ATT but stabilized upon reaching a cut-off of 8 mm ATT. In addition, ATT did have a significant influence on [HHb] amplitude. In participants with ATT < 8 mm, higher amplitudes were observed with increasing intensity whereas in participants with ATT > 8 mm, there were no differences between the intensities.</p><p><strong>Conclusion: </strong>The study reveals variable results with regards to reliability and there was no consistent influence of exercise intensity on reliability. Participants with a lower skinfold thickness showed stronger reliability. Moreover, NIRS signals decrease when ATT exceeds 8 mm. Careful consideration is necessary when interpreting NIRS signals in such cases.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1061-1073"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142686316","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":"Maximal oxygen uptake, pulmonary function and walking economy are not impaired in patients diagnosed with long COVID.","authors":"O K Berg, N Aagård, J Helgerud, M F Brobakken, J Hoff, E Wang","doi":"10.1007/s00421-024-05652-7","DOIUrl":"10.1007/s00421-024-05652-7","url":null,"abstract":"<p><strong>Introduction: </strong>SARS-CoV-2 may result in the development of new symptoms, known as long COVID, a few months after the original infection.</p><p><strong>Purpose: </strong>It is elusive to what extent physical capacity in patients diagnosed with long COVID is impacted.</p><p><strong>Methods: </strong>We compared maximal oxygen uptake (V̇O_2max), one of the single most important factors for cardiovascular health and mortality, expired lung volumes and air flow, oxygen cost of walking and 6-min-walking-test (6MWT), in 20 patients diagnosed with long COVID (11 males and 9 females; 44 ± 16 years (SD); 26.7 ± 3.8BMI, duration of acute phase 1.7 ± 1.2 weeks, tested 4 ± 3 months after long COVID diagnosis) with 20 healthy age and sex matched controls (11 males and 9 females; 44 ± 16 years; 25.9 ± 4.0BMI).</p><p><strong>Results: </strong>Long COVID patients had a V̇O_2max of 41.4 ± 16.2 mL∙kg^-1∙min^-1(men) and 38.2 ± 7.5 (women) and this was not different from controls. Similarly, mean spirometry measures in the patient group (VC; FVC; FEV₁; FEV₁/FVC) were also not different (85-106%) from predicted healthy values. Finally, inclined treadmill (5%, 4 km∙h^-1) walking economy was not different between the groups (long COVID: 15.2 ± 1.1 mL∙kg^-1∙min^-1; controls: 15.2 ± 1.2 mL∙kg^-1∙min^-1), while the 6MWT revealed a difference (long COVID: 606 ± 118 m; controls: 685 ± 85 m; p = 0.036).</p><p><strong>Conclusion: </strong>V̇O_2max, oxygen cost of walking, and spirometry measurements did not appear to be impaired in patients diagnosed with long COVID with a prior mild to moderate SARS-CoV-2 infection. The typical outcomes in these essential factors for health and longevity implies that while long COVID can present with a range of symptoms, caution should be made when attributing these symptoms directly to compromised pulmonary function or V̇O_2max.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1157-1166"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950012/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142750368","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":"Increasing set volume relative to baseline does not augment skeletal muscle adaptations when compared to maintenance of baseline training volume in recreationally trained individuals.","authors":"Enrique N Moreno, Danielle T Sampson, Elias C Figueroa, Matthew B Jessee, Samuel L Buckner","doi":"10.1007/s00421-024-05655-4","DOIUrl":"10.1007/s00421-024-05655-4","url":null,"abstract":"<p><strong>Purpose: </strong>This study compared the effects of prescribing an increased number of sets relative to baseline (ITV) to a maintenance of baseline training volume (BTV), in previously trained individuals.</p><p><strong>Methods: </strong>Forty-two adults with more than 6 months of elbow flexion resistance training experience had each arm randomized to either the ITV or BTV condition. Participants performed 2-weekly sessions of unilateral standing dumbbell elbow flexion exercise for 12 weeks, 8 of which were supervised. Muscle thickness of the elbow flexors at 50, 60, and 70% the distance of the upper arm and one repetition-maximum (1RM) strength for the unilateral standing dumbbell elbow flexion exercise were assessed pre- and post-intervention.</p><p><strong>Results: </strong>For the 50% site, there was no evidence that the changes were different between BTV and ITV [∆BTV vs ∆ITV (cm) = 0.022 (95% CI - 0.096, 0.140)]. However, there was evidence that both conditions observed a greater change compared to the control. For the 60% site, there was no evidence that the changes were different between BTV and ITV [∆BTV vs ∆ITV (cm) = - 0.010 (95% CI - 0.155, 0.96)]. However, there was evidence that both conditions observed a greater change compared to the control. For the 70% site, there was no evidence that the changes were different between BTV and ITV [∆BTV vs ∆ITV (cm) = 0.004 (95% CI - 0.092, 0.101)]. However, there was evidence that both conditions observed a greater change compared to the control. For changes in 1RM, there was evidence that the change was greater in the BTV [∆BTV vs ∆Control (kg) = 1.915 (95% CI 1.219, 2.611)] and ITV [∆ITV vs ∆Control (kg) = 1.780 (95% CI 1.084, 2.475)] conditions compared to control.</p><p><strong>Conclusion: </strong>Prescribing an increased dose of sets relative to baseline did not augment muscular adaptations when compared to a maintenance of BTV, in recreationally trained individuals. Both training conditions were similarly effective in promoting significant increases in muscle thickness and 1RM strength of the elbow flexors.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1049-1059"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142667699","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":"Boys vs men differences in muscular fatigue, muscle and cerebral oxygenation during maximal effort isometric contractions: the effect of muscle blood flow restriction.","authors":"Leonidas Kastritseas, Aggelos Koutlas, Anastasios Kounoupis, Stella Kritikou, Stavros Papadopoulos, Ilias Smilios, Konstantina Dipla, Andreas Zafeiridis","doi":"10.1007/s00421-024-05670-5","DOIUrl":"10.1007/s00421-024-05670-5","url":null,"abstract":"<p><strong>Purpose: </strong>To examine whether the children's superiority, over adults, to resist fatigue during repeated maximal-efforts depends on their often-cited oxidative advantage, attributed to greater muscle blood flow and O₂-delivery. We also investigated the mechanisms underlying child-adult differences in muscle-oxygenation (due to O₂-supply or O₂-utilization) and examined if there are age-differences in cerebral-oxygenation response (a brain-activation index).</p><p><strong>Methods: </strong>Eleven men (23.3 ± 1.8yrs) and eleven boys (11.6 ± 1.1 yrs) performed 15 maximal-effort handgrips (3-s contraction/3-s rest) under two conditions: free-flow circulation (FF) and arterial-occlusion (OCC). Force, muscle-oxygenation (TSImuscle) and cerebral-oxygenation (oxyhemoglobin-O₂Hbcerebral; total hemoglobin-tHbcerebral; deoxyhemoglobin-HHbcerebral) were assessed.</p><p><strong>Results: </strong>In boys, force declined less (- 26.3 ± 2.6 vs. - 34.4 ± 2.4%) and at slower rate (- 1.56 ± 0.16 vs. - 2.24 ± 0.17%·rep^-1) vs. men in FF (p < 0.01-0.05; d = 0.60-1.24). However, in OCC there were no age-differences in the magnitude (- 38.3 ± 3.0 vs. - 37.8 ± 3.0%) and rate (- 2.44 ± 0.26 vs. - 2.54 ± 0.26%·rep^-1) of force decline. Boys compared to men, exhibited less TSImuscle decline in both protocols, and lower muscle VO₂ (p < 0.05). Boys, also, presented a smaller O₂Hbcerebral and tHbcerebral rise than men in FF; exercising with OCC increased the O₂Hbcerebral and tHbcerebral response in boys. Using MVIC as a covariate in FF condition, abolished boys-men differences in force and TSImuscle decline and O₂Hbcerebral rise.</p><p><strong>Conclusion: </strong>During repeated maximal-efforts: (i) blood flow is a significant contributor to children's superiority over adults to resist fatigue; (ii) age-difference in muscle hypoxia/deoxygenation is rather attributed to men's greater metabolic demand than to lower muscle-perfusion; and (iii) cerebral oxygenation/blood volume increase more in men than boys under free circulation, implying greater brain activation.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1191-1203"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142750365","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":"Causal relationship between strenuous exercise and muscle injury: a Mendelian randomization study with dual samples.","authors":"Xin Huang, Longxiang Huang, Changhua Liu","doi":"10.1007/s00421-024-05669-y","DOIUrl":"10.1007/s00421-024-05669-y","url":null,"abstract":"<p><strong>Background: </strong>Muscle injuries, particularly those resulting from irregular bouts of strenuous exercise, have become a significant public health issue, especially among the athletic population. The physiological mechanisms linking intense physical exertion to muscle damage remain incompletely understood, necessitating further investigation to elucidate the causal pathways involved.</p><p><strong>Purpose: </strong>The objective of this systematic review is to explore the physiological mechanisms that may underlie the causal relationship between strenuous exercise and the incidence of muscle injury.</p><p><strong>Study design: </strong>A systematic review was conducted to synthesize available evidence on the topic.</p><p><strong>Methods: </strong>We utilized advanced Mendelian randomization techniques with dual cohorts to analyze single-nucleotide polymorphisms (SNPs) significantly associated with strenuous exercise (P < 5 × 10^-8). Data on muscle injuries in the wrist and hand muscle, hips, and thighs were sourced from genome-wide association studies (GWAS) databases. A comprehensive sensitivity analysis was performed, incorporating inverse variance weighting, weighted median, MR-Egger regression, multicollinearity assessment, heterogeneity evaluation, and leave-one-out analyses.</p><p><strong>Results: </strong>Our findings reveal a significant positive correlation between strenuous exercise and the risk of muscle injury in the hips and thighs (OR = 1.0046062, 95% CI [0.0004911795, 0.008700143], p = 0.028195794). In contrast, no causal link was identified between strenuous exercise and muscle injury in the wrist and hand muscle (OR = 0.9989059, 95% CI [-0.01131070, 0.009121317], p = 0.8336501).</p><p><strong>Conclusion: </strong>The present systematic review suggests that strenuous exercise is positively associated with an increased risk of muscle injury in the lower limbs. This association appears to be mediated through physiological mechanisms that are more pronounced in the lower extremities compared to the wrist and hand muscle. Further research is warranted to dissect the intricate physiological processes that contribute to this differential susceptibility to injury.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"989-999"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142766105","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":"Acute exercise impacts heart rate variability but not cognitive flexibility during subsequent simulated firefighter occupational tasks.","authors":"Philip J Agostinelli, Nicholas C Bordonie, Braxton A Linder, Ann M Robbins, Parker L Jones, Lee F Reagan, C Brooks Mobley, Matthew W Miller, William M Murrah, JoEllen M Sefton","doi":"10.1007/s00421-024-05650-9","DOIUrl":"10.1007/s00421-024-05650-9","url":null,"abstract":"<p><strong>Purpose: </strong>Acute exercise can transiently enhance cognitive flexibility. The cognitive demand of firefighters makes it relevant to understand if on-shift exercise could produce similar improvements in cognitive performance during subsequent occupational tasks. Metrics of heart rate variability (HRV), such as time- and frequency-domain outcomes, may shed light upon the influence exercise has on cognition, as they discern information related to cardiac autonomic (sympathetic/parasympathetic) function. We aimed to determine if acute resistance and aerobic exercise impact cognitive flexibility during occupational tasks and its relation to HRV.</p><p><strong>Methods: </strong>32 participants completed a baseline Wisconsin Card Sorting Task (WCST) and three experimental trials: resistance exercise (RE), aerobic exercise (AE), or a rested control (CON). An occupational task assessment (OTA) including four rounds of 10 deadlifts and a 0.15-mile sandbag carry in an environmental chamber (35 °C/50% humidity) was completed after each trial. The second round was followed by the WCST. Repeated measures ANOVAs were used to analyze differences by condition.</p><p><strong>Results: </strong>For the WCST, total, perseverative, and non-perseverative errors did not differ (ps > 0.39). Time-domain HRV metrics were not different (ps > 0.05). All frequency-domain metrics, other than low-frequency power, were not different (ps > 0.24). Low-frequency power was lower based on condition (p = 0.03). Post hoc analysis showed low-frequency power was lower following AE compared to RE and CON.</p><p><strong>Conclusion: </strong>Results suggest an acute bout of on-shift aerobic or resistance exercise may not impact cognitive flexibility during subsequent simulated occupational tasks, despite depressed metrics of heart rate variability following aerobic exercise.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1037-1048"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950049/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142616933","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}