European Journal of Applied Physiology最新文献

{"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":"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}

{"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":"Impact loading exercise induced osteogenesis from childhood to early adulthood in tennis players aged 8-30 years.","authors":"George Vagenas, Dimitria Palaiothodorou","doi":"10.1007/s00421-024-05681-2","DOIUrl":"10.1007/s00421-024-05681-2","url":null,"abstract":"<p><p>Osteogenesis with impact-loading exercise is often assessed by the extra bone growth induced in the loaded arm of tennis players. We used PRISMA to explore % bone mineral content (BMC) and area (BA) asymmetry in players 8-30 years according to weekly training hours, age, sex, maturity, and bone segment. Proper statistics for 70 groups were extracted by two reviewers from 18 eligible studies of low risk of bias (< 35, STROBE) and good quality (> 70%). The quality of the review was high (AMSTAR, 81%). Using \"random effects\" we tested moderation-specific meta-comparisons and meta-regressions. The loaded bones % hypertrophy was higher in BMC (19%) than BA (10%), and, with BMC and BA merged, in boys (17%) than girls (13%), in humerus (19%) than radius-ulna (14%), and in pubertal (19%) players. Weekly training hours were more important (43%) than sex (17%), puberty (14%) and bone (15%) in BMC, and puberty (48%) was more important than weekly training hours (19%), sex (12%), and radius-ulna (5%) in BA. The loaded bones % hypertrophy correlated with weekly training hours highly (> 0.60) in all maturity groups for BMC and BA, and moderately (0.41) in early adults for BA; it also correlated with age (≥ 0.60) in children and peripubertal players, but not (0.037) with starting age. Impact loading exercise favors mineralization twice than bone expansion, while puberty favors bone expansion about three times more than mineralization. The bone gains are higher for boys than girls, and for peripubertal than older players. The bone growth implications are discussed considering limitations and future research.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"909-936"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143002515","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":"Effect of experimental knee pain location on gait kinematics.","authors":"Alessio Gallina, Paola Adamo, Giorgia Marino, Corrado Cescon, Francesco Bolzoni, Marco Barbero, Federico Temporiti, Roberto Gatti","doi":"10.1007/s00421-024-05648-3","DOIUrl":"10.1007/s00421-024-05648-3","url":null,"abstract":"<p><strong>Purpose: </strong>In this study, we investigated whether experimental knee pain alters lower limb kinematics and knee arthrokinematics during gait, and if this motor adaptation depends on the spatial characteristics of the painful stimulus.</p><p><strong>Methods: </strong>Twenty-one participants walked on a treadmill for 60-s trials, either without stimulation or while experiencing painful electrical stimulation in the medial, lateral or anterior region of the knee. Perceived pain location was analyzed using pain drawing. Gait spatiotemporal parameters, lower limb kinematics, and dispersion of the knee helical axes on the sagittal plane were quantified for each trial and compared between conditions using ANOVAs with repeated measures or Friedman tests.</p><p><strong>Results: </strong>Pain perception was localized in the area the stimulation was applied to. Compared to walking without pain, participants demonstrated reduced knee extension (1.5 ± 1.5 degrees, p = 0.002) and reduced hip extension (0.8 ± 1.1 degrees, p = 0.037) when pain was induced in the anterior region, but not medially or laterally. Anterior knee pain increased the mean distance of the helical axes during late stance (0.7 [0.3, 1.4], p = 0.010), while medial pain increased both mean distance (0.3 [0.1, 0.5], p = 0.037) and mean angle (1.2 ± 1.4, p = 0.010) during early swing.</p><p><strong>Conclusion: </strong>Acute, experimental knee pain alters gait kinematics and increases the dispersion of the helical axis. These adaptations depend on the spatial characteristics of the painful stimulus. These adaptations may reflect an attempt of the central nervous system to protect the painful tissue while searching for a less painful movement strategy.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"977-987"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950027/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142616954","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":"Taurine supplementation as a strategy to enhance thermoregulation during low-intensity exercise.","authors":"Gabriela Ferreira Abud, Ellen Cristini de Freitas","doi":"10.1007/s00421-025-05776-4","DOIUrl":"https://doi.org/10.1007/s00421-025-05776-4","url":null,"abstract":"","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143751747","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":"Skeletal muscle hypertrophy and enhanced mitochondrial bioenergetics following electrical stimulation exercises in spinal cord injury: a randomized clinical trial.","authors":"Ashraf S Gorgey, Refka E Khalil, William Carter, Jeannie Rivers, Qun Chen, Edward J Lesnefsky","doi":"10.1007/s00421-024-05661-6","DOIUrl":"10.1007/s00421-024-05661-6","url":null,"abstract":"<p><p>We examined the combined effects of neuromuscular electrical stimulation-resistance training (NMES-RT) and functional electrical stimulation-lower extremity cycling (FES-LEC) compared to passive movement training (PMT) and FES-LEC on mitochondrial electron transport chain (ETC) complexes and citrate synthase (CS) in adults with SCI. Thirty-two participants with chronic SCI were randomized to 24 weeks of NMES-RT + FES [n = 16 (14 males and 2 females) with an age range of 20-54 years old] or PMT + FES [n = 16 (12 males and 4 females) with an age range of 21-61 years old]. The NMES-RT + FES group underwent 12 weeks of surface NMES-RT using ankle weights followed by an additional 12 weeks of FES-LEC. The PMT + FES performed 12 weeks of passive leg extension movements followed by an additional 12 weeks of FES-LEC. Using repeated measures design, muscle biopsies of the vastus lateralis were performed at baseline (BL), post-intervention 1 (P1) and post-intervention 2 (P2). Spectrophotometer was used to measure ETC complexes (I-III) and CS using aliquots of the homogenized muscle tissue. Magnetic resonance imaging was used to measure skeletal muscle CSAs. A time effect was noted on CS (P = 0.001) with an interaction between both groups (P = 0.01). 46% of the participants per group had zero activities of CI without any changes following both interventions. A time effect was noted in CII (P = 0.023) following both interventions. Finally, NMES-RT + FES increased CIII at P1 compared to BL (P = 0.023) without additional changes in P2 or following PMT + FES intervention. Skeletal muscle hypertrophy may potentially enhance mitochondrial bioenergetics after SCI. NMES-RT is likely to enhance the activities of complex III in sedentary persons with SCI. Clinical trials # NCT02660073.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1075-1089"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11950031/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142692654","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":"Effects of different postures on the hemodynamics and cardiovascular autonomic control responses to exercise in postural orthostatic tachycardia syndrome.","authors":"Carolina P Andrade, Antonio R Zamunér, Franca Barbic, Alberto Porta, Stefano Rigo, Dana A Shiffer, Aurelien Bringard, Nazzareno Fagoni, Guido Ferretti, Raffaello Furlan","doi":"10.1007/s00421-024-05662-5","DOIUrl":"10.1007/s00421-024-05662-5","url":null,"abstract":"<p><strong>Purpose: </strong>To assess the effects of two different body positions on the cardiovascular autonomic profile during a single bout of exercise in patients with postural orthostatic tachycardia syndrome (POTS).</p><p><strong>Methods: </strong>Thirteen patients with POTS and thirteen healthy controls (C) participated in the study. ECG, respiration, beat-by-beat arterial pressure and O₂ consumption (VO2) were continuously recorded while on a cycle ergometer in supine and upright positions, before and during exercise (6 min, 50 Watts). Spectral analysis of RR intervals and systolic arterial pressure (SAP) variability provided indexes of cardiac sympathovagal interaction (LF/HF ratio), cardiac vagal modulation (HF_RR, high-frequency component of RR variability, ~ 0.25 Hz), sympathetic vasomotor control (LF_SAP, low-frequency component of SAP variability, 0.1 Hz) and baroreflex sensitivity (BRS, α_LF).</p><p><strong>Results: </strong>While supine, patients with POTS showed lower HF_RR and α_LF, greater heart rate (HR), LF/HF and LF_SAP, compared with C, suggesting cardiovascular sympathetic over-activity and reduced BRS. While sitting upright, POTS showed greater HR and reduced HF_RR and α_LF compared with C. During supine exercise, SAP, HR, LF/HF increased and HF_RR and α_LF decreased similarly in POTS and C. In POTS, upright sitting exercise was associated with slightly higher <math> <mrow><mover><mi>V</mi> <mo>˙</mo></mover> <msub><mi>O</mi> <mn>2</mn></msub> </mrow> </math> , a greater increase in HR whereas LF_SAP was lower than in C.</p><p><strong>Conclusion: </strong>Upright exercise was associated with excessive enhancement of HR and a blunted increase of the sympathetic vasomotor control in POTS. Conversely, supine exercise-induced hemodynamic and autonomic changes similar in POTS and C, thus making supine exercise potentially more suitable for physical rehabilitation in POTS.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1091-1099"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142695201","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 age and physical activity status on muscle synergies when walking down slopes.","authors":"Laura Nash, Vincent C K Cheung, Amitabh Gupta, Roy T H Cheung, Borong He, Matthew Liston, Daniel Thomson","doi":"10.1007/s00421-024-05679-w","DOIUrl":"10.1007/s00421-024-05679-w","url":null,"abstract":"<p><strong>Purpose: </strong>The aim of the current study was to determine whether gait control (muscle synergies) or gait stability (margin of stability (MoS)) were different between younger and older adults when walking on level or downhill slopes. Further, it sought to determine associations between either age or physical activity with muscle synergy widths.</p><p><strong>Methods: </strong>Ten healthy younger (28.1 ± 8.0 years) and ten healthy older (69.5 ± 6.3 years) adults walked at their preferred walking speed on a treadmill at different slopes (0˚, - 4˚ and - 8˚). Muscle synergies were extracted using non-negative matrix factorisation and compared between groups and walking slopes. Correlations between the full width at half maximum (FWHM) of the synergies' activations and weekly recreational physical activity minutes and age were also determined.</p><p><strong>Results: </strong>Younger and older adults both walked with similar muscle synergies across all tested slopes, with 4 synergies accounting for > 85% variance of overall muscle activity in both groups across all tested slopes, with high scalar products (≥ 0.86) for each synergy and slope. It was also demonstrated that physical activity and age had different associations with pooled muscle synergies across slopes, as weekly minutes spent in recreational physical activity were associated with the FWHM of a synergy activated at weight acceptance, whereas age was associated with the FWHM of synergies occurring at push off and foot clearance, respectively.</p><p><strong>Conclusion: </strong>Our results suggest that healthy older and younger adults walk with similar muscle synergies on downhill slopes, and that physical activity and age influence different muscle synergies during walking.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1139-1156"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142750296","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 blood flow and vascular responses in dynamically exercising skeletal muscles evoked by combination of cold stimulation and voluntary apnea in humans.","authors":"Ryoko Matsutake, Tomomi Fujimoto, Masashi Ichinose, Kazuhito Watanabe, Naoto Fujii, Takeshi Nishiyasu","doi":"10.1007/s00421-024-05643-8","DOIUrl":"10.1007/s00421-024-05643-8","url":null,"abstract":"<p><strong>Purpose: </strong>We evaluated (1) the combined effects of cold stimulation and voluntary breath holding (apnea) on heart rate, blood pressure, blood flow and vascular responses in dynamically exercising muscles in humans, and (2) if some interactions exist between cold stimulation and apnea on the cardiovascular responses.</p><p><strong>Methods: </strong>Nine males and 1 female performed three trials entailing a dynamic two-legged knee extension exercise at a constant workload that elicited heart rates around 100 beats min^-1. During the trials the participants performed either: (1) immersed their right hand into ice water maintained at 4 °C (cold pressor test; CPT); (2) performed maximal-duration apnea; and (3) performed a combination of CPT and apnea. Leg blood flow (LBF) and cardiac output (CO) were measured simultaneously using two Doppler ultrasound systems.</p><p><strong>Results: </strong>CPT induced a rise in mean arterial pressure (MAP) (P < 0.05) but had no significant effect on CO or exercising leg vascular conductance (LVC). Apnea evoked large pressor responses, bradycardia and decreases in CO, LBF and LVC (all P < 0.05). The increase in MAP induced by combined CPT and apnea was smaller than the sum of those induced separately by CPT or apnea (P < 0.05). Combined CPT and apnea decreased LBF and LVC to a similar extent as apnea alone.</p><p><strong>Conclusion: </strong>Addition of local cold stimulation to apnea does not enhance pressor responses or vasoconstriction within active muscles. This suggests that maximum voluntary apnea evokes massive vasoconstriction, even within exercising muscles, which cannot be enhanced by additional sympathetic stimulation.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":"1179-1190"},"PeriodicalIF":2.8,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142715651","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}