Journal of applied physiology最新文献

{"title":"Mild hypohydration in healthy older adults increases pain-related brain activity without affecting pain perception: A single-blind study.","authors":"Thomas A Deshayes, Félix-Antoine Savoie, Timothée Pancrate, Antoine Jolicoeur Desroches, José A Morais, Pierre-Michel Bernier, Guillaume Léonard, Ivan L Simoneau, Eric D B Goulet","doi":"10.1152/japplphysiol.00870.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00870.2024","url":null,"abstract":"<p><p>Understanding how hydration status influences pain perception is particularly important in older adults, as both dehydration and pain are prevalent in this population. Ten individuals (70 ± 4 years) completed two randomized and counterbalanced trials. They were exposed to passive heat until they lost 1% body mass through sweat and urine (~ 100 min), with the loss either unreplaced (sham infusion, HYPO) or fully replaced via 0.45% saline infusion (EUH). Nociceptive electrical stimulation was applied to the sural nerve (1) before heat exposure (baseline), (2) 60 min following hydration manipulation (R60, ~ 160 min after baseline); (3) after mouth rinsing with water (MR, ~ 170 min after baseline) and; (4) following water ingestion (ING, ~ 185 min after baseline). Pain-related event-related potentials were assessed using electroencephalography (EEG) at R60, MR, and ING. After hydration manipulation, body mass loss and plasma osmolality were greater, and plasma volumes was lower in HYPO compared to EUH, although thirst did not differ between the conditions. There were no differences between the two conditions regarding pain intensity and unpleasantness. Still, EEG analyses revealed that the peak-to-peak amplitude of the pain-related N200-P300 potential (~ 136 - 310 ms) was significantly greater in HYPO compared to EUH (<i>p</i> = 0.036), and significantly greater in R60 compared to both MR (<i>p</i> = 0.01) and ING (<i>p</i> = 0.03), either with HYPO and EUH. These results suggest that mild hypohydration in healthy older adults may influence some neurophysiological processes related to nociception without significantly affecting pain perception.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142828572","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":"Characterization of Upper Esophageal Sphincter Pressures Relative to Vocal Acoustics.","authors":"Jesse D Hoffmeister, Jüergen Konczak, Stephanie N Misono","doi":"10.1152/japplphysiol.00385.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00385.2024","url":null,"abstract":"<p><p>Strength of vocal fold adduction has been hypothesized to be a critical factor influencing voice quality, but has been difficult to measure directly during phonation. Recent work has suggested that UES pressure, which can be easily assessed, increases with stronger vocal fold adduction, raising the possibility that UES pressure might indirectly reflect vocal fold adduction strength. However, concurrent UES pressure and voice quality have not previously been examined across different vocal tasks. Doing so may offer insights into the potential use of UES pressure for relative quantification of the strength of vocal fold adduction, and how this might contribute to voice quality across different vocal tasks. We assessed UES pressure relative to voice quality in 32 vocally healthy adults during sustained vowels, whispered sentences, and spoken sentences. Smoothed cepstral peak prominence (CPPs) and low-to-high spectral energy ratio (LHR) were derived from the acoustic signal as measures of voice quality. After controlling for resting UES pressure, age, and sex, we observed significant negative correlations between UES pressure and CPPs, and a significant positive correlation between UES pressure and LHR. UES pressures were significantly higher during spoken sentences than whispered sentences and sustained vowels.. Measuring UES pressure relative to acoustic measures of voice quality is a novel methodology for studying upper aerodigestive tract physiology during phonation, and has potential to enhance understanding of voice disruption in clinical populations. Clinical implications and considerations for implementation are discussed.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142789512","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":"Daily blood flow restriction does not affect muscle fiber capillarization and satellite cell content during two weeks of bed rest in healthy young men.","authors":"Thorben Aussieker, Cas J Fuchs, Antoine Zorenc, Lex B Verdijk, Luc J C van Loon, Tim Snijders","doi":"10.1152/japplphysiol.00461.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00461.2024","url":null,"abstract":"<p><p>The present study assessed whether single-leg daily blood flow restriction (BFR) treatment attenuates the decline in muscle fiber size, capillarization, and satellite cell (SC) content during 2 weeks of bed rest in healthy, young men. Twelve healthy, young men (age: 24±3 y; BMI: 23.7±3.1 kg/m²) were subjected to 2 weeks of bed rest, during which one leg was exposed to three times daily 5 min of BFR, whereas the contralateral leg received sham treatment (CON). Muscle biopsies were obtained from the <i>M. vastus lateralis</i> from both the BFR and CON leg before and immediately after the 2 weeks of bed rest. Type I and II muscle fiber size, myonuclear content, capillarization, and SC content were assessed by immunohistochemistry. No significant decline in either type I or type II muscle fiber size were observed following bedrest, with no differences between the CON and BFR leg (<i>P</i>>0.05). Type I muscle fiber capillary density increased in response to bed rest in both legs (<i>P</i><0.05), while other muscle fiber capillarization measures remained unaltered. SC content decreased in both type I (from 7.4±3.2 to 5.9±2.7 per 100 fibers) and type II (from 7.2±3.4 to 6.5±3.2 per 100 fibers) muscle fibers (main effect of time <i>P</i>=0.018), with no significant differences between the BFR and CON leg (<i>P</i>>0.05). In conclusion, two weeks of bed rest has no effect on muscle capillarization, decrease the SC content and daily BFR treatment does not affect skeletal muscle fiber size and SC content in healthy, young men.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142769265","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":"Multidimensional assessment of exertional dyspnea in young healthy males and females who select unsatisfied inspiration at peak exercise.","authors":"Reid A Mitchell, Alanna S Hind, Olivia N Ferguson, Morgan Flynn, Jem Arnold, Satvir S Dhillon, Neil D Eves, A William Sheel, Jordan A Guenette","doi":"10.1152/japplphysiol.00420.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00420.2024","url":null,"abstract":"<p><p>Historically, it was thought that healthy humans predominantly described their breathing as a sense of increased work or effort (W/E) during maximal exercise. However, emerging data shows that many healthy adults select unpleasant dyspnea descriptors such as \"unsatisfied inspiration\" (UI), with relatively more females selecting UI than males. We hypothesized that males and females who select UI would report higher dyspnea intensity ratings during exercise; select more distressing dyspnea qualities post-exercise; and have greater inspiratory constraints than those who do not. Sixty-four healthy, non-smokers (32M:32F; 23±5yr) completed questionnaires, pulmonary function tests, and maximal incremental cycling with detailed dyspnea evaluation. Males in UI and Non-UI subgroups reported similar Borg 0-10 dyspnea intensity ratings of W/E, UI, and unsatisfied expiration (UE) (all <i>P</i>>0.05). Females in the UI subgroup reported significantly higher UI and UE ratings than females in the Non-UI subgroup (both <i>P</i><0.01). Both UI subgroups reported greater air hunger, chest tightness, and mental breathing effort than Non-UI participants (all <i>P</i><0.05). In males only, masculine gender was negatively correlated (r=-0.402, <i>P</i>=0.02) and anxiety positively correlated (r=0.363, <i>P</i>=0.04) with submaximal UI ratings. Females with UI had smaller peak tidal volume (V_T) (1.74 (0.32) vs 2.06 (0.33) L, <i>P</i>=0.03) than Non-UI females; and V_T was negatively correlated with submaximal (r=-0.496, <i>P</i>=0.004) and peak (r=-0.495, <i>P</i>=0.004) UI ratings in all females. There were no differences in V_T or correlations between V_T and dyspnea in male subgroups. Absolute lung volumes and psychosocial factors appear important in understanding sex differences in the perception of UI during exercise.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":""},"PeriodicalIF":3.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142769267","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":"Cadence-based energy expenditure in able-bodied male people comparing cadence-based energy expenditure and oxygen cost indices in able-bodied male people.","authors":"Juntaek Hong, Jehyeon Yu, Juyeon Lee, Dain Shim, Tae Young Choi, Ye Bin Cho, Jeuhee Lee, Dong-Wook Rha","doi":"10.1152/japplphysiol.00294.2024","DOIUrl":"10.1152/japplphysiol.00294.2024","url":null,"abstract":"<p><p>Walking is a fundamental aspect of daily life and exercise, with clinical benefits for cardiovascular health and muscle strength. However, accurately measuring energy efficiency during walking poses challenges due to equipment and spatial constraints. In this study, we proposed the cadence-based energy expenditure index (cEEI) and analyzed its correlation with the previously proposed index for measuring energy expenditure under various gait conditions. We enrolled 15 healthy participants and conducted an experimental protocol on a treadmill to measure the following energy expenditure-related indices: oxygen cost index (OCI), energy expenditure index (EEI), and cEEI. The participants underwent stages of walking at different speeds and inclinations that comply with the modified Bruce protocol, whereas their heart rate, oxygen uptake, and cadence were recorded. Participants showed significant increases in heart rate, oxygen uptake, and cadence with higher walking speeds and inclinations. Correlation analysis revealed strong associations between cEEI and OCI, especially during walking conditions. Bland-Altman plots and interclass correlation coefficient analysis demonstrated a favorable agreement between cEEI and OCI, outperforming EEI. In conclusion, this study proposes cEEI as a reliable metric for estimating energy expenditure during walking by proving a strong correlation and agreement with OCI across various gait conditions. This suggests the potential for cEEI to provide real-time, individualized feedback on energy expenditure during walking, facilitating more personalized exercise prescriptions.<b>NEW & NOTEWORTHY</b> We proposed cEEI as a reliable metric for estimating energy expenditure under various walking conditions. Its demonstrated accuracy and potential for real-time individualized feedback could revolutionize personalized exercise prescriptions for diverse sexes and age groups, as well as individuals with disabilities requiring real-time physical monitoring and home care.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"1604-1611"},"PeriodicalIF":3.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142466234","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":"Effects of two carbonic anhydrase inhibitors on exercise performance in acute hypoxia.","authors":"Jou-Chung Chang, Benjamin P Thompson, Connor J Doherty, Leah M Mann, Antonia N Berdeklis, Glen E Foster, A Russell Tupling, Erik R Swenson, Paolo B Dominelli","doi":"10.1152/japplphysiol.00589.2024","DOIUrl":"10.1152/japplphysiol.00589.2024","url":null,"abstract":"<p><p>Acute mountain sickness (AMS) occurs due to rapid altitude ascents and/or insufficient acclimatization. Acetazolamide (AZ) is commonly prescribed for AMS prophylaxis but inhibits exercise performance. Methazolamide (MZ), an analogous drug, has similar prophylactic benefits but does not impair isolated muscle mass exercise performance in normoxia. We sought to compare whole body exercise performance in acute hypoxia (fraction of inspired oxygen, [Formula: see text] = 0.15) between AZ, MZ, and placebo (PLA). Fifteen healthy participants completed five testing visits: <i>day 1</i> for maximal exercise test, <i>day 2</i> for familiarization, and <i>days 3</i>-<i>5</i> were the experimental visits. Each experimental visit involved a 5-km hypoxic cycling time trial (TT) performed after a 2-day dosing protocol of either AZ (250 mg three times a day), MZ (100 mg twice a day), or PLA (three times a day); the order was randomized and double-blinded. Before exercise, capillary blood samples were taken, and maximal voluntary contractions of quadriceps were performed. AZ and MZ resulted in a partially compensated metabolic acidosis at rest compared with PLA [capillary hydrogen ions (H⁺) 47 ± 3, 43 ± 2, and 39 ± 2 nmol for AZ, MZ, and PLA respectively, <i>P</i> < 0.01]. Time to complete 5 km with PLA (562 ± 32 s, <i>P</i> < 0.01) was significantly faster than AZ and MZ (577 ± 38 vs. 581 ± 37 s, respectively), with no differences between AZ and MZ (<i>P</i> = 0.96). There were no differences in average ventilation (124 ± 27, 127 ± 24, 127 ± 19 L/min) and oxyhemoglobin saturation (87 ± 2, 88 ± 2, 88 ± 3%) between AZ, MZ, and PLA, respectively (<i>P</i> > 0.05). Overall, both AZ and MZ impair whole body exercise performance in acute normobaric hypoxia.<b>NEW & NOTEWORTHY</b> Administration of acetazolamide (AZ) and methazolamide (MZ) both resulted in a significantly slower 5-km time trial in acute normobaric hypoxia compared with a placebo. Both drugs lead to a partially compensated metabolic acidosis, but ventilation and oxyhemoglobin saturation were not different across the conditions. Overall, acetazolamide and methazolamide both impaired whole body exercise performance in acute normobaric hypoxia but potentially have different mechanisms of action.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"1566-1579"},"PeriodicalIF":3.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545675","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":"Marked hemoglobin mass expansion and plasma volume contraction in Sherpas acclimatizing to 5,400 m altitude.","authors":"Johanna Roche, Santosh Baniya, Suraj Bhatta, Sachin Subedi, Hannes Gatterer, Peter Rasmussen, Matthias Peter Hilty, Anne-Aylin Sigg, Santosh Timalsina, Christoph Siebenmann","doi":"10.1152/japplphysiol.00247.2024","DOIUrl":"10.1152/japplphysiol.00247.2024","url":null,"abstract":"<p><p>In lowlanders, high altitude (HA) acclimatization induces hemoconcentration by reducing plasma volume (PV) and increasing total hemoglobin mass (Hb_mass). Conversely, Tibetan highlanders living at HA are reported to have a similar hemoglobin concentration ([Hb]) as lowlanders near sea level, and we investigated whether this reflects alterations in the PV or the Hb_mass response to HA. Baseline assessment of PV and Hb_mass was performed by carbon monoxide rebreathing at low altitudes (∼1,400 m) in Sherpas (an ethnic group of Tibetans living in Nepal) and native lowlanders. Participants then ascended to the Everest Base Camp (EBC) (5,400 m), where further measurements were performed after ∼2 days (EBC 1) and ∼6 wk (EBC 2). While on EBC 1 an increase in [Hb] was observed in lowlanders (<i>P</i> = 0.004) but not in Sherpas (<i>P</i> = 0.179), marked increases in [Hb] were observed in both groups on EBC 2 (<i>P</i> < 0.001). On EBC 1, Hb_mass (Sherpas, <i>P</i> = 0.393; lowlanders, <i>P</i> = 0.123) and PV (Sherpas, <i>P</i> = 0.348; lowlanders, <i>P</i> = 0.172) were not different from baseline in either group, while circulating erythropoietin was increased in both groups (<i>P</i> < 0.001). On EBC 2, large increases in Hb_mass and reductions in PV were observed along with elevated circulating erythropoietin in both groups (all <i>P</i> < 0.002). Neither the increases in erythropoietin on EBC 1 (<i>P</i> = 0.846) or EBC 2 (<i>P</i> = 0.564) nor the expansion of Hb_mass (<i>P</i> = 0.771) or reduction in PV (<i>P</i> = 0.099) on EBC 2 differed between the groups. We conclude that the hematological response of Sherpas to extended exposure to very high altitudes does not fundamentally differ from that of native lowlanders.<b>NEW & NOTEWORTHY</b> We measured the hematological response to ∼6 wk exposure to an altitude of 5,400 m in Sherpa highland natives and Nepalese lowlanders. While the increase in hemoglobin concentration at high altitudes tended to be smaller in Sherpas than in lowlanders, the two groups experienced a similar reduction in plasma volume and increase in hemoglobin mass. We conclude that the hematological response of Sherpas to high-altitude exposure does not fundamentally differ from that of lowlanders.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"1632-1641"},"PeriodicalIF":3.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604670","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 of dietary supplementation of glycocalyx precursors on vascular function in type 2 diabetes.","authors":"James A Smith, Francisco I Ramirez-Perez, Katherine Burr, Juan D Gonzalez-Vallejo, Mariana Morales-Quinones, Neil J McMillan, Larissa Ferreira-Santos, Neekun Sharma, Christopher A Foote, Luis A Martinez-Lemus, Jaume Padilla, Camila Manrique-Acevedo","doi":"10.1152/japplphysiol.00651.2024","DOIUrl":"10.1152/japplphysiol.00651.2024","url":null,"abstract":"<p><p>Degradation of the endothelial glycocalyx in type 2 diabetes (T2D) is thought to contribute to impaired shear stress mechanotransduction, leading to endothelial dysfunction and the development of cardiovascular disease. Herein, we tested the hypothesis that restoration of the endothelial glycocalyx with dietary supplementation of glycocalyx precursors (DSGPs, containing glucosamine sulfate, fucoidan, superoxide dismutase, and high-molecular weight hyaluronan) improves endothelial function and other indices of vascular function in T2D. First, in db/db mice, we showed that treatment with DSGP (100 mg/kg/day) for 4 wk restored endothelial glycocalyx length, as assessed via atomic force microscopy in aortic explants. Restoration of the glycocalyx with DSGP was accompanied by improved flow-mediated dilation (FMD) and reduced arterial stiffness in isolated mesenteric arteries. Further corroborating these findings, the treatment of cultured endothelial cells with that same mixture of glycocalyx precursors promoted glycocalyx growth. Next, as an initial step to investigate the translatability of these findings, we conducted a pilot (<i>n</i> = 22) double-blinded randomized placebo-controlled clinical trial to assess the effects of DSGP (3,712.5 mg/day) for 8 wk on endothelial glycocalyx integrity and indices of vascular function, including FMD, in Veterans with T2D. Contrary to the hypothesis, DSGP neither enhanced endothelial glycocalyx integrity nor improved vascular function indices relative to placebo. Together, these findings conceptually support the notion that restoration of the endothelial glycocalyx can lead to improvements in vascular function in a mouse model of T2D; however, DSGP as a therapeutic strategy to enhance vascular function in individuals with T2D does not appear to be efficacious.<b>NEW & NOTEWORTHY</b> Endothelial glycocalyx degradation in type 2 diabetes (T2D) is thought to contribute to impaired shear stress mechanotransduction, leading to vascular dysfunction. The findings of this study support the notion that restoration of the endothelial glycocalyx using a dietary supplementation of glycocalyx precursors can lead to improvements in vascular function in diabetic mice. However, the utilized dietary supplement as a therapeutic strategy to enhance vascular function in individuals with T2D is not efficacious.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"1592-1603"},"PeriodicalIF":3.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545677","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":"Exercise cardiovascular magnetic resonance shows improved diastolic filling by atrioventricular area difference in athletes and controls.","authors":"Jonathan Edlund, Björn Östenson, Einar Heiberg, Håkan Arheden, Katarina Steding-Ehrenborg","doi":"10.1152/japplphysiol.00446.2024","DOIUrl":"10.1152/japplphysiol.00446.2024","url":null,"abstract":"<p><p>Hydraulic force, a novel mechanism shown to aid diastolic filling, can be calculated by assessing the geometrical relationship between the left ventricular and atrial short-axis areas (atrioventricular area difference, AVAD) (Maksuti E, Carlsson M, Arheden H, Kovács SJ, Broomé M, Ugander M. <i>Sci Rep</i> 7: 43505-43510, 2017; Steding-Ehrenborg K, Hedström E, Carlsson M, Maksuti E, Broomé M, Ugander M, Magnusson M, Smith JG, Arheden H. <i>J Appl Physiol (1985)</i> 130: 993-1000, 2021). During exercise both ventricular and atrial volumes change due to altered loading conditions compared with rest, but it is unknown to what extent this affects AVAD. The aim of this study was to investigate whether AVAD differs when going from rest to exercise in sedentary controls and athletes. We included 13 sedentary controls and 20 endurance athletes to undergo cardiovascular magnetic resonance (CMR) imaging at rest and during moderate and vigorous exercise using a CMR-compatible ergometer. AVAD was calculated as the largest ventricular short-axis area minus the largest atrial short-axis area in end-diastole (ED) and end-systole (ES) as measured from CMR short-axis images. AVAD in ED increased during moderate exercise in both sedentary controls and athletes, thus aiding diastolic filling, but did not increase further during vigorous exercise. AVAD in ES was negative in both groups at rest and decreased further with increasing exercise intensity in sedentary controls, whereas athletes remained unchanged. In conclusion, results from AVAD in ED indicate the net hydraulic force to further augment diastolic filling during moderate exercise when compared with rest, providing new insights into the mechanism by which diastolic function increases during exercise.<b>NEW & NOTEWORTHY</b> This study is the first to assess hydraulic force during exercise, a novel mechanism shown to augment diastolic filling at rest. Our results indicate hydraulic force to further aid in diastolic filling during moderate exercise compared with rest in athletes and sedentary controls, providing new insights into the mechanism by which the left ventricle increases diastolic function during exercise.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"1554-1562"},"PeriodicalIF":3.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142466236","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":"Mechanistic insights and clinical applications of age and sex differences in the oxygen cost of breathing.","authors":"Octavia G Garcia-Murillo, Silvia G Cazarez-Higuera, Alberto Blanco-Salazar, Isaac A Chávez-Guevara","doi":"10.1152/japplphysiol.00856.2024","DOIUrl":"https://doi.org/10.1152/japplphysiol.00856.2024","url":null,"abstract":"","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":"137 6","pages":"1612-1613"},"PeriodicalIF":3.3,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142818049","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}