Experimental Physiology最新文献

{"title":"How hot is too hot for people? A review of empirical models of perceptual, physiological and functional limits of human heat tolerance.","authors":"Davide Filingeri, Nuno Koch Esteves","doi":"10.1113/EP092242","DOIUrl":"https://doi.org/10.1113/EP092242","url":null,"abstract":"<p><p>How hot is too hot for people? This is a question that human thermal physiologists are asked often by a variety of knowledge users across the public and private sectors, who have grown aware of the negative impact of global warming on people's health and quality of life. The aim of this paper is to provide a narrative review of models that quantify the limits of human heat tolerance across perceptual, physiological and functional domains. Several models exist that have identified critical environmental limits for heat tolerance across the perceptual, physiological and functional domains. However, no model is currently available that has evaluated all domains of heat tolerance concurrently and in the same participant cohort. Hence, by combining evidence from these models, here we propose a new holistic framework of heat tolerance that can help more comprehensively characterise the full spectrum of possible human responses to heat stress under free-living conditions. This framework highlights that human heat tolerance varies largely across the perceptual, physiological and functional domains, and that it is conceptually organised in line with the human body's ability to regulate body temperature via behavioural and autonomic responses. While our new framework presents limitations in its generalisability beyond healthy young adult cohorts, we hope that it will inspire the design of new holistic research on human heat tolerance in a broader range of participant cohorts, to better inform person-centred heat resilience policies and interventions that protect human health and life quality under a warming climate.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144947891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early acclimatization to high altitude: Acid-base and fluid balance dynamics during the first 2 days at 3100 m.","authors":"Elisabeth Skalla, Benedikt Treml, Sasa Rajsic, Michael Schreinlechner, Zoran Bukumirić, Klaus Berek, Alexander Egger, Johann Knotzer, Martin Burtscher, Axel Kleinsasser","doi":"10.1113/EP093029","DOIUrl":"https://doi.org/10.1113/EP093029","url":null,"abstract":"<p><p>Immediate responses to hypoxia at high altitude are hyperventilation and successive respiratory alkalosis. Alkalosis, in turn, can affect cerebrospinal fluid pH and ventilatory control. The kidneys compensate metabolically for respiratory alkalosis. The time line and detailed sequence of these renal compensatory processes have not been explored thoroughly. We examined the initial adjustments of acid-base and fluid balances during the first 2 days at high altitude.  Twelve unacclimatized adults of either sex were transported to 3100 m a.s.l. at the Sonnblick Observatory (Austria). Measurements (fluid and acid-base balance and arterial blood gases) were performed before and 24 and 44 h after arrival. Exposure to high altitude provoked hyperventilation, resulting in hypocapnia and alkalosis. Altitude diuresis started immediately after arrival at altitude. The only metabolic response within the first 24 h was a slight reduction in plasma bicarbonate, but after 44 h distinct reductions in bicarbonate and a trend change in altitude-corrected base excess and arterial pH were observed. Hyperventilation and increased diuresis appeared immediately upon exposure to high altitude, whereas compensatory bicarbonate excretion showed the first influence on the arterial pH at the 44 h measurement. Further research is needed to explore differences in individual responses in the setting of antedated or carry-over acclimatization.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144946524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Downregulation of microRNA-494 drives mitochondrial biogenesis and function in trained muscle.","authors":"Natália Pálešová, Klára Gabrišová, Jana Babulicová, Patrik Krumpolec, Zuzana Kovaničová, Tímea Kurdiová, Salvatore Modica, Christian Wolfrum, Jozef Ukropec, Barbara Ukropcová, Miroslav Baláž","doi":"10.1113/EP092977","DOIUrl":"https://doi.org/10.1113/EP092977","url":null,"abstract":"<p><p>MicroRNAs (miRNAs) are key regulators of cellular processes, including mitochondrial function and energy metabolism. This study explores the regulation of miR-494 in skeletal muscle and circulation, investigating its response to exercise training and an acute exercise bout, its association with metabolic disorders, and the effects of electrical pulse stimulation (EPS). In addition, it validates the gene targets and physiological role of miR-494 using gain- and loss-of-function studies in primary human skeletal muscle cells. We demonstrate that miR-494 levels in both skeletal muscle and circulation are influenced by long-term exercise training, which induces adaptive changes, but remain unaffected by an acute bout of exercise. EPS does not alter miR-494 levels in cultured primary human skeletal muscle cells. Moreover, muscle miR-494 levels remain unchanged under various metabolic challenges, including obesity and type 2 diabetes. Genetic manipulation of miR-494 in primary human skeletal muscle cells modulates mitochondrial biogenesis and function, as well as lipid metabolism, through targeting PGC1A and SIRT1. Injection of a miR-494 inhibitor into skeletal muscle of mice supports the role of miR-494 in regulating Pgc1α mRNA, suggesting potential therapeutic implications. These findings highlight miR-494 as a significant modulator of mitochondrial dynamics and energy metabolism in skeletal muscle.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144948138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing the predictive validity of NIRS kinetic profiles to predict aerobic capacity from a resting skeletal muscle occlusion test.","authors":"Heru Syarli Lesmana, Kyohei Marume, Justin S Lawley","doi":"10.1113/EP092899","DOIUrl":"https://doi.org/10.1113/EP092899","url":null,"abstract":"&lt;p&gt;&lt;p&gt;Measuring and monitoring individual cardiorespiratory fitness through a valid and accessible non-exhaustive surrogate is required. Techniques measuring haemodynamics have shown promise, and this study aimed to optimize the predictive validity of these approaches alongside developing predictive equations. In a two-study design, 8 (pilot study) and 30 (confirmation study) healthy adults completed exercise testing to assess maximal oxygen consumption ( &lt;math&gt; &lt;semantics&gt; &lt;msub&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt; &lt;mo&gt;̇&lt;/mo&gt;&lt;/mover&gt; &lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;O&lt;/mi&gt; &lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt; &lt;mi&gt;max&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;annotation&gt;${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; ) and an ischaemic occlusion test on the upper thigh to assess superficial femoral blood flow from ultrasonography and skeletal muscle oxygenation (SmO&lt;sub&gt;2&lt;/sub&gt;) by near-infrared spectroscopy (NIRS) before, during and post-cuff release. In study 1, treadmill running and a 5-min 220 mmHg ischaemic cuff pressure were performed, whereas in study 2, cycling ergometry and a 3-min 300 mmHg cuff pressure were applied. In study 1 and study 2, &lt;sub&gt;abs&lt;/sub&gt; &lt;math&gt; &lt;semantics&gt; &lt;msub&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt; &lt;mo&gt;̇&lt;/mo&gt;&lt;/mover&gt; &lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;O&lt;/mi&gt; &lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt; &lt;mi&gt;max&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;annotation&gt;${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; and &lt;sub&gt;rel&lt;/sub&gt; &lt;math&gt; &lt;semantics&gt; &lt;msub&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt; &lt;mo&gt;̇&lt;/mo&gt;&lt;/mover&gt; &lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;O&lt;/mi&gt; &lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt; &lt;mi&gt;max&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;annotation&gt;${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; were correlated to peak blood flow post-cuff occlusion (r = 0.57-0.84, all P &lt; 0.01). In study 2, several NIRS based metrics of post-occlusive reactive hyperaemia were strongly correlated with &lt;sub&gt;abs&lt;/sub&gt; &lt;math&gt; &lt;semantics&gt; &lt;msub&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt; &lt;mo&gt;̇&lt;/mo&gt;&lt;/mover&gt; &lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;O&lt;/mi&gt; &lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt; &lt;mi&gt;max&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;annotation&gt;${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; and &lt;sub&gt;rel&lt;/sub&gt; &lt;math&gt; &lt;semantics&gt; &lt;msub&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt; &lt;mo&gt;̇&lt;/mo&gt;&lt;/mover&gt; &lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;O&lt;/mi&gt; &lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt; &lt;mi&gt;max&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;annotation&gt;${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; (all P &lt; 0.001). Moreover, the magnitude of oxygen desaturation during the cuff occlusion was highly significantly related to both &lt;sub&gt;abs&lt;/sub&gt; &lt;math&gt; &lt;semantics&gt; &lt;msub&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt; &lt;mo&gt;̇&lt;/mo&gt;&lt;/mover&gt; &lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;O&lt;/mi&gt; &lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt; &lt;mi&gt;max&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;annotation&gt;${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; and &lt;sub&gt;rel&lt;/sub&gt; &lt;math&gt; &lt;semantics&gt; &lt;msub&gt;&lt;mover&gt;&lt;mi&gt;V&lt;/mi&gt; &lt;mo&gt;̇&lt;/mo&gt;&lt;/mover&gt; &lt;mrow&gt;&lt;msub&gt;&lt;mi&gt;O&lt;/mi&gt; &lt;mn&gt;2&lt;/mn&gt;&lt;/msub&gt; &lt;mi&gt;max&lt;/mi&gt;&lt;/mrow&gt; &lt;/msub&gt; &lt;annotation&gt;${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$&lt;/annotation&gt;&lt;/semantics&gt; &lt;/math&gt; (all P &lt; 0.001). As an example, the SmO&lt;sub&gt;2&lt;/sub&gt; desaturation slope was strongly","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144947977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Validation of muscle oxygenation kinetics to predict aerobic fitness and exercise transition thresholds.","authors":"Heru Syarli Lesmana, Ben Schroeder, Kyohei Marume, Patrick Rodrigues, Justin S Lawley","doi":"10.1113/EP092908","DOIUrl":"https://doi.org/10.1113/EP092908","url":null,"abstract":"<p><p>The aim of this study was to validate previously developed equations to predict maximal oxygen uptake ( <math> <semantics> <msub><mover><mi>V</mi> <mo>̇</mo></mover> <mrow><msub><mi>O</mi> <mn>2</mn></msub> <mi>max</mi></mrow> </msub> <annotation>${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$</annotation></semantics> </math> ) from near-infrared spectroscopy (NIRS) during and after a period of limb ischaemia. Moreover, NIRS recovery kinetics after steady-state exercise (SSE) could be used to monitor <math> <semantics> <msub><mover><mi>V</mi> <mo>̇</mo></mover> <mrow><msub><mi>O</mi> <mn>2</mn></msub> <mi>max</mi></mrow> </msub> <annotation>${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$</annotation></semantics> </math> and exercise intensity thresholds. Seventeen healthy adults completed a 3 min 300 mmHg pressure cuff occlusion to measure the occlusion slope, relative rate of muscle reoxygenation at 10 s (Rep 10s), baseline (R_bl), peak (R_peak) and area under the curve (AUC_2min). SSE was performed at 100 W (SSE1) and 150 W (SSE2) to determine the relative rate of muscle reoxygenation (R1_bl and R2_bl). Thereafter, incremental maximal cycling was used to determine <math> <semantics> <msub><mover><mi>V</mi> <mo>̇</mo></mover> <mrow><msub><mi>O</mi> <mn>2</mn></msub> <mi>max</mi></mrow> </msub> <annotation>${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$</annotation></semantics> </math> , ventilatory thresholds (VTs) and gross efficiencies (GEs). The values of Rep 10s (r = 0.61, p = 0.02), R_bl (r = 0.53, p = 0.04), R_peak (r = 0.60, p = 0.02), AUC_2min (r = 0.67, p < 0.01) and occlusion slope (r = -0.68, p = 0.005) were correlated with absolute <math> <semantics> <msub><mover><mi>V</mi> <mo>̇</mo></mover> <mrow><msub><mi>O</mi> <mn>2</mn></msub> <mi>max</mi></mrow> </msub> <annotation>${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$</annotation></semantics> </math> . After steady-state cycling, SSE1 R_bl was correlated with absolute <math> <semantics> <msub><mover><mi>V</mi> <mo>̇</mo></mover> <mrow><msub><mi>O</mi> <mn>2</mn></msub> <mi>max</mi></mrow> </msub> <annotation>${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$</annotation></semantics> </math> (r = 0.67, p = 0.01) and relative <math> <semantics> <msub><mover><mi>V</mi> <mo>̇</mo></mover> <mrow><msub><mi>O</mi> <mn>2</mn></msub> <mi>max</mi></mrow> </msub> <annotation>${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$</annotation></semantics> </math> (r = 0.60, p = 0.02), in addition to absolute VT1 (r = 0.66, p = 0.01) and relative VT1 (r = 0.61 p = 0.02). The SSE2 R_bl was correlated with absolute <math> <semantics> <msub><mover><mi>V</mi> <mo>̇</mo></mover> <mrow><msub><mi>O</mi> <mn>2</mn></msub> <mi>max</mi></mrow> </msub> <annotation>${dot V_{{{mathrm{O}}_{mathrm{2}}}{mathrm{max}}}}$</annotation></semantics> </math> (r = 0.58, p = 0.02), relative <math> <semantics>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144947994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mapping the variability of in vivo rat uterine electrical properties throughout the oestrous cycle.","authors":"Mathias W Roesler, Amy S Garrett, Leo K Cheng, Alys R Clark","doi":"10.1113/EP092704","DOIUrl":"https://doi.org/10.1113/EP092704","url":null,"abstract":"<p><p>After reaching sexual maturity, uterine function is driven by cyclical variations in hormone levels. The electrical and mechanical activity in the uterus varies during the menstrual cycle, contributing to essential functions such as sperm transport and shedding the menstrual lining. However, there is a lack of quantification of the variation in uterine function occurring over the course of the cycle. Female Wistar rats were used to quantify the changes in uterine electrical activity in vivo with respect to the oestrous cycle. Under anaesthesia, the uterus was exteriorised, and electrodes were placed on the dorsal and ventral sides of the organ to record spontaneous activity from the serosa. Electrical events were separated into slow and fast components based on frequency. The duration and interval between events were measured and propagation directions and velocities were mapped along the uterus using high spatial resolution electrode arrays. All stages of the oestrous cycle showed ovarian-cervical propagation, but cervical-ovarian propagation was also present in pro-oestrus and metoestrus. Ovarian-cervical propagation was dominant in oestrus and metoestrus. The interval between events showed significant differences with 40.2 ± 5.6 s (1.51 ± 0.25 cpm) and 60.5 ± 2.6 s (1.02 ± 0.05 cpm) during the dioestrus and metoestrus phases, respectively (P < 0.001). The slow and fast component durations were similar across the oestrous cycle (19.9 ± 2.2 s and 10.2 ± 3.0 s, respectively). This emphasizes the role of the oestrous cycle in guiding uterine function through modulation of the electrical activity and shows potential for estimating the oestrous cycle phases based on electrical characteristics.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144947917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of agomelatine in appetite regulation and body weight in rats.","authors":"Engin Korkmaz, Yavuz Erden, Çiğdem Tekin, Suat Tekin","doi":"10.1113/EP092783","DOIUrl":"https://doi.org/10.1113/EP092783","url":null,"abstract":"<p><p>The hypothalamic nuclei play a central role in the synthesis of anorexigenic and orexigenic neuropeptides, which are regulated by peripheral hormones, like leptin and ghrelin. Melatonergic receptors (MT₁/MT₂) are prominently expressed in the arcuate nucleus of the hypothalamus - an essential hub for appetite control - and in peripheral metabolic tissues where leptin and ghrelin are secreted. Agomelatine, an antidepressant drug and potent MT₁/MT₂ agonist, offers potential for modulating appetite. This study aimed to investigate the impact of agomelatine on appetite regulation. Forty male Sprague-Dawley rats were randomly allocated into four groups, control (no treatment), vehicle control, agomelatine 20 mg/kg (Ago-20), and agomelatine 40 mg/kg (Ago-40), and administered oral gavage for 14 days. Body weight and food intake were recorded daily. At the end of the experiment, rats were euthanized and blood and hypothalamic tissue samples were obtained. Agomelatine significantly reduced body weight (Ago-40: 275.2 ± 7.2 g vs. control: 339.7 ± 8.3 g, P < 0.05) and food intake (Ago-40: 20.21 ± 1.32 g vs. control: 32.09 ± 1.58 g, P < 0.05) by day 14, without affecting water intake. Plasma ghrelin levels decreased (Ago-40: 22.54 ± 3.95 ng/dL vs. control: 46.67 ± 4.84 ng/dL, P < 0.05), while leptin increased (Ago-40: 552.30 ± 41.67 pg/mL vs. control: 271.10 ± 32.12 pg/mL P < 0.05). Hypothalamic orexigenic neuropeptides neuropeptide Y (NPY) and agouti-related peptide (AgRP) were suppressed (NPY, Ago40: 0.61 ± 0.02 vs. Control: 1.36 ± 0.1321; AgRP, Ago40: 0.52 ± 0.03 vs. Control: 1.49 ± 0.27, P < 0.05), while anorexigenic cocaine- and amphetamine-regulated transcript (CART) and proopiomelanocortin (POMC) were elevated (CART: Ago40: 1.19 ± 0.08 vs. Control: 0.92 ± 0.06; POMC: Ago40: 1.49 ± 0.17 vs. Control: 0.67 ± 0.10, P < 0.05). These findings suggest agomelatine promotes weight loss by modulating appetite-related hormones and hypothalamic neuropeptides, highlighting its potential as a therapeutic for obesity and metabolic disorders.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144834664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of 12 weeks of upper-body rowing exercise on autonomic cardiovascular control and vascular structure in spinal cord-injured humans.","authors":"Rasmus Kopp Hansen, Rasmus Bering, Claus Graff, Stefanos Volianitis, Uffe Laessoe, Afshin Samani, Ryan Godsk Larsen","doi":"10.1113/EP092667","DOIUrl":"https://doi.org/10.1113/EP092667","url":null,"abstract":"<p><p>Spinal cord injury (SCI) is characterized by autonomic cardiovascular dysfunction that may contribute to the three- to fourfold greater risk of heart disease and stroke compared to non-injured individuals. While exercise training elicits beneficial changes in autonomic function and vascular structure in healthy individuals, it is unclear if similar adaptations occur in individuals with SCI. Adults with chronic SCI (>1 year post injury) were randomized to 12 weeks of supervised upper-body rowing exercise (UBROW; 3×/week; n = 8), adhering to current exercise guidelines, or control (CON; n = 9). Autonomic cardiovascular control was assessed by heart rate variability (HRV; electrocardiography) and blood pressure responses to a sit-up test (finger plethysmography). Brachial (peripheral) and carotid (central) artery diameter and wall thickness (near- and far-wall carotid intima-media-thickness) were measured using high-resolution ultrasound. All measurements were conducted at baseline, after 6 and 12 weeks. There was no effect of UBROW on time and frequency domain HRV or blood pressure responses to the sit-up test (group-by-time interactions: P ≥ 0.28; effect sizes: η_p ² ≤ 0.11). For UBROW, brachial artery diameter increased from 4.80 ± 0.72 mm at baseline to 5.08 ± 0.91 mm after 12 weeks (P < 0.05, η_p ² = 0.27). Carotid artery dimensions did not change, and there were no correlations between changes (baseline-12 weeks) in brachial artery diameter and changes in HRV outcomes (r ≤ 0.40, P ≥ 0.14). While upper-body rowing exercise enlarged brachial artery diameter, carotid artery dimensions and autonomic cardiovascular control did not change, suggesting local vascular remodelling, but no systemic vascular adaptations, in response to a supervised 12-week exercise intervention in spinal cord-injured humans.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144834663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Watching the eye with Mars in sight.","authors":"Peter Zu Eulenburg, Lonnie Petersen, Damian M Bailey","doi":"10.1113/EP092974","DOIUrl":"https://doi.org/10.1113/EP092974","url":null,"abstract":"","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144816151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isometric training at longer muscle-tendon complex lengths: A potential countermeasure to impaired neuro-muscle-tendon function during space travel.","authors":"Gerard McMahon, Andy Sanderson, Hans Degens","doi":"10.1113/EP092225","DOIUrl":"https://doi.org/10.1113/EP092225","url":null,"abstract":"<p><p>Manned space exploration to distant destinations, including Mars, continues to be an aspiration of humankind. Space travel does, however, present many challenges to the body, amongst which adaptation to microgravity is perhaps the largest. For instance, both short and long manned spaceflight missions have shown substantial deleterious effects on muscle size and neuromuscular function. Although the neuro-muscle-tendon system is responding primarily to the load to which it is subjected, resistive exercise countermeasures with dynamic contractions during space travel do not entirely mitigate the space travel-induced deteriorations in neuro-muscle-tendon function, probably owing to a lack of overall accumulation of sufficient mechanical stress. The aim of this review is to evaluate the evidence for isometric resistance training at longer muscle-tendon complex lengths to mitigate microgravity-induced deterioration in neuro-muscle-tendon function better than conventional resistance-training programmes. It has been shown that specific joint positions, associated with a longer muscle-tendon complex, require larger internal muscle forces for the same external torque, thus requiring more muscle activation and imposing more tendon strain than during conventional dynamic resistance training. Isometric resistance training also confers the advantage of requirement of less voluminous equipment, in comparison to that required for dynamic resistive exercise. This factor is particularly important for space travel owing to the physical space and mass constraints. In addition, isometric contractions allow for easier monitoring and progression in exercise prescription compared with dynamic contractions.</p>","PeriodicalId":12092,"journal":{"name":"Experimental Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-08-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144816150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}