Journal of applied physiology最新文献

{"title":"Influence of work intensity on acute kidney injury risk during simulated occupational heat stress.","authors":"Hayden W Hess, Molly E Heikkinen, Erica Tourula, M Jo Hite, Kelli Rivers, Roger S Zoh, Blair D Johnson, David Hostler, Zachary J Schlader","doi":"10.1152/japplphysiol.00590.2024","DOIUrl":"10.1152/japplphysiol.00590.2024","url":null,"abstract":"<p><p>Violation of the National Institute of Occupational Safety and Health (NIOSH) heat stress recommendations by exceeding the allowable wet bulb globe temperature (WBGT) for a given work intensity and work-rest ratio augments acute kidney injury (AKI) risk. Here, we tested the hypothesis that exceeding the allowable work intensity at a given WBGT and work-rest ratio would also worsen AKI risk. Twelve healthy adults completed two NIOSH recommendation compliant trials and one noncompliant trial consisting of a 4 h (half workday) exposure. Work-rest ratio was fixed at 30 min of walking and 30 min of rest each hour. Work intensity (metabolic heat production) was prescribed as a function of WBGT-412 ± 51 W [27.3 ± 0.3°C; high-intensity compliant (C_high)], 290 ± 75 W [31.6 ± 0.2°C; low-intensity compliant (C_low)], and 410 ± 61 W [31.7 ± 0.2°C; high-intensity noncompliant (NC_high)]. AKI risk was quantified by the product of urinary insulin-like growth factor-binding protein 7 and tissue inhibitor of metalloproteinase 2 normalized to urine specific gravity ([IGFBP7·TIMP-2]_USG). Peak core temperature was higher in NC_high trial (38.3 ± 0.4°C) compared with the compliant trials (C_high: 38.0 ± 0.3°C; C_low: 37.8 ± 0.4°C; <i>P</i> ≤ 0.0095). [IGFBP7·TIMP-2]_USG increased from pre- to immediately postexposure in all trials (time effect: <i>P</i> = 0.0454) but the peak increase was not different between trials [C_high: 0.89 ± 1.7 (ng/mL)²/1,000; C_low: 0.78 ± 1.7 (ng/mL)²/1,000; NC_high: 1.0 ± 1.4 (ng/mL)²/1,000; <i>P</i> = 0.7811]. Violating the NIOSH recommendations by exceeding either the allowable work intensity (i.e., NC_high vs. C_low) or WBGT (i.e., NC_high vs. C_high) resulted in a modest elevation in peak core temperature but did not modify AKI risk.<b>NEW & NOTEWORTHY</b> We demonstrate that violation of the National Institute for Occupational Safety and Health heat stress recommendations by exceeding allowable work intensity by ∼120 W or environmental limits by ∼4°C wet bulb globe temperature (WBGT) at 30-min work-rest per hour results in a modest elevation in peak core temperature but does not augment acute kidney injury risk compared with scenarios that adhered to the NIOSH recommendations during simulated occupational heat stress.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"706-717"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143039002","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":"Alterations in the intersegmental coordination of landing from a jump in a microgravity environment.","authors":"Thibaut D Toussaint, Jean-Matthieu Pypaert, Clément N Gambelli, Bénédicte Schepens","doi":"10.1152/japplphysiol.00511.2024","DOIUrl":"10.1152/japplphysiol.00511.2024","url":null,"abstract":"<p><p>The objective is to investigate the intersegmental coordination during landing from a countermovement jump in different gravitational environments to gain insight on how humans perceive gravity and coordinate complex motor tasks. Eight participants performed countermovement jumps on Earth (1 <i>g</i>) and while submitted to four simulated gravity levels (from 0.2 to 1 <i>g</i>) generated by a downward pull-down force in weightlessness induced by parabolic flights. The orientation of body segments (i.e., elevation angles) was recorded using a high-speed camera. A principal component analysis was performed on the elevation angles of the foot, shank, thigh, and trunk segments together with a correlation analysis. Regardless of the environment, the movements of the four body segments are tuned through a law of intersegmental coordination; the vertical position of the center of mass of the body being identified as the parameter controlled. The movement of the foot seems an independent factor, given its minimal contribution to the intersegmental coordination and the poor correlation with the shank segment. In weightlessness, the intersegmental coordination is less unidimensional and more variable compared with Earth's gravity. In addition, the lower the gravity level simulated in weightlessness, the greater the contribution of the foot and of the shank, and the lower the contribution of the thigh, suggest an adjustment of the intersegmental coordination through a reweighting of altered sensory inputs. In conclusion, the intersegmental coordination remains better optimized for Earth gravity, but the unidimensional synergy is preserved in weightlessness when using a downward pull-down force to simulate gravity.<b>NEW & NOTEWORTHY</b> During landing, the movements of the trunk, thigh, shank, and foot are tuned through a unidimensional synergy, identified as the vertical position of the center of mass. In microgravity, the coordination is overall less unidimensional and more variable compared with Earth's gravity, suggesting a suboptimal coordination. In lower microgravity levels, greater contribution of the foot and of the shank, and lower contribution of the thigh suggest an adjustment through a reweighting of sensory inputs.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"848-856"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143523411","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":"Combining hyperpolarized ¹²⁹Xe MR imaging and spectroscopy to noninvasively estimate pulmonary vascular resistance.","authors":"Anna Costelle, Junlan Lu, Suphachart Leewiwatwong, Berend Westerhof, David Mummy, Sudarshan Rajagopal, Bastiaan Driehuys","doi":"10.1152/japplphysiol.00440.2024","DOIUrl":"10.1152/japplphysiol.00440.2024","url":null,"abstract":"<p><p>Hyperpolarized ¹²⁹Xe MRI/MRS enables quantitative mapping of function in lung airspaces, membrane tissue, and red blood cells (RBCs) within the pulmonary capillaries. The RBC signal also exhibits cardiogenic oscillations that are reduced in precapillary pulmonary hypertension (PH). This effect is obscured in patients with concomitant defects in transfer from airspaces to RBCs, which increase RBC oscillation amplitudes. Here, we provide a framework for interpreting RBC oscillations and show their relationship to pulsatile blood flow, capillary blood volume, capillary compliance, and impedance of the capillary and venous circulation. This framework was first applied to characterize RBC oscillations in a cohort of subjects with pulmonary disease but no known PH (<i>n</i> = 129). ¹²⁹Xe MRI of RBC transfer was used to estimate capillary blood volume, and as it decreased, RBC oscillations sharply increased ([Formula: see text] = 0.53), consistent with model predictions. Model-derived fit parameters were then used to estimate the distribution of pulmonary vascular resistance (PVR) across arterial, capillary, and venous circulation and to correct oscillations for RBC transfer defects. Seventy percent of PVR was estimated to arise from pulmonary arteries, 11% from capillaries, and 19% from veins. When tested in a second cohort of subjects who underwent ¹²⁹Xe MRI/MRS and right heart catheterization (<i>n</i> = 40), oscillations corrected for capillary blood volume correlated moderately with PVR (<i>r</i>² = 0.27, <i>P</i> = 0.0014). For every 1.96 Wood units (WU) increase in PVR, corrected oscillations decreased by 1 absolute percentage point. This work demonstrates that, although ¹²⁹Xe-RBC oscillations are only indirectly sensitive to precapillary obstruction, corrected oscillations below 7.5% were 100% specific for elevated PVR.<b>NEW & NOTEWORTHY</b> Cardiogenic oscillations in the ¹²⁹Xe red blood cell (RBC) resonance decrease in precapillary pulmonary hypertension (PH) but are enhanced when capillary blood volume is reduced. To separate these effects, we developed a physiological model that used ¹²⁹Xe gas exchange MRI to estimate blood volume, which was used to correct oscillation amplitude measurements. Corrected amplitudes correlated significantly with pulmonary vascular resistance, highlighting the potential for future noninvasive detection of PH.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"623-633"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143052642","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":"Interactions of chronic stress exposure and stress appraisal on vascular endothelial function among young adults.","authors":"Alyssa S Carlson, Laura E Schwager, Thomas W Hart, Sara J Diesel, Jordan L Harris, Mark Flores, Kylee S West, Emily B K Thomas, Nathaniel D M Jenkins","doi":"10.1152/japplphysiol.00457.2024","DOIUrl":"10.1152/japplphysiol.00457.2024","url":null,"abstract":"<p><p>We investigated the associations of ongoing, chronic stress exposure and stress appraisal on vascular endothelial function (VEF) in young adults. In 72 healthy young adults (74% female; age = 25 ± 1 yr), we assessed chronic stress exposure and appraisal with a measure that quantified chronic stress exposure and chronic stress appraisal related to eight specific stressors over the last year. Participants completed the perceived stress scale (PSS) as a measure of global, proximal stress appraisal. VEF was assessed using the brachial artery flow-mediated dilation technique. We examined relations among ongoing, chronic stress exposure and stress appraisal versus VEF adjusted for age and sex, and then assessed whether stress appraisal moderated the effect of chronic stress exposure on VEF. Chronic stress exposure (β = -0.24, <i>P</i> = 0.045), but not chronic stress appraisal (β = 0.07, <i>P</i> = 0.56) or perceived stress (β = -0.20, <i>P</i> = 0.11), was related to VEF. Perceived stress (<i>P</i> = 0.046), but not chronic stress appraisal (<i>P</i> = 0.54), moderated the association between chronic stress exposure and VEF. The effect of chronic stress exposure on VEF ceased to be significant at a PSS score of ∼22. Subsequent exploratory stratified analysis indicated that those with PSS ≥22 had increased exposure to adverse childhood experiences (+1.6 ± 0.6, <i>P</i> = 0.01), greater depressive symptoms (+10.2 ± 2.7, <i>P</i> < 0.001), and reduced psychological resilience (-7.6 ± 3.5, <i>P</i> = 0.036). Chronic stress exposure significantly predicts impaired VEF among young adults. Furthermore, this relation is influenced by proximal perceived stress, such that the association of chronic stress exposure on VEF may be obscured at high levels of proximal perceived stress.<b>NEW & NOTEWORTHY</b> Our findings indicate that ongoing chronic stress exposure over the last year is significantly associated with reduced vascular endothelial function among apparently healthy young adults. Our data provide important insights into the interplay of chronic stress exposure versus proximal perceived stress and may also support the hypothesis that young adults who are sensitized to stress may be particularly vulnerable to stress-related impairments in vascular endothelial function.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"783-791"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142983522","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 contractile activity induces the activation of the mitochondrial integrated stress response and the transcription factor ATF4.","authors":"Victoria C Sanfrancesco, David A Hood","doi":"10.1152/japplphysiol.00307.2024","DOIUrl":"10.1152/japplphysiol.00307.2024","url":null,"abstract":"<p><p>Skeletal muscle relies on mitochondria to produce energy and support its metabolic flexibility. The function of the mitochondrial pool is regulated by quality control (MQC) processes. The integrated stress response (ISR), a MQC pathway, is activated in response to various cellular stressors. The transcription factor ATF4, the main effector of the ISR, ameliorates cellular stress by upregulating protective genes, such as CHOP and ATF5. Recent literature has shown that the ISR is activated upon mitochondrial stress; however, whether this includes acute exercise-induced stress is poorly defined. To investigate this, a mouse in situ hindlimb protocol was utilized to acutely stimulate muscles at 0.25, 0.5, and 1 tetanic contraction/s for 9 min, followed by a 1-h recovery period. CAMKIIα and JNK2 were robustly activated sixfold immediately after the protocol. ISR activation, denoted as the ratio of phosphorylated to total eIF2α protein levels, was also elevated after recovery. Downstream, contractile activity induced an increase in the nuclear localization of ATF4. Robust twofold increases in the mRNA expression of ATF4 and CHOP were also observed after the recovery period. Changes in ATF4 mRNA were independent of transcriptional activation, as assessed with an ATF4 promoter-reporter plasmid. Instead, mRNA decay assays revealed an increase in ATF4 mRNA stability post contractile activity, as a result of enhanced stabilization by the RNA binding protein HuR. Thus, acute contractile activity is sufficient to induce mitochondrial stress and activate the ISR, corresponding to the induction of ATF4 with potential consequences for mitochondrial phenotype adaptations in response to repeated exercise.<b>NEW & NOTEWORTHY</b> The integrated stress response (ISR) is a mitohormetic stress response critical for the maintenance of mitochondrial homeostasis. However, its role in mediating mitochondrial adaptations with exercise-induced stress is not well established. This research demonstrates that acute contractile activity can elicit mitochondrial stress and activate the ISR to maintain mitochondrial homeostasis via the enhancement of the functioning of ATF4, illustrating an early response to exercise that promotes mitochondrial health and adaptations.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"857-871"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142466231","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":"Transfer of balance performance depends on the specificity of balance training.","authors":"Alex Rizzato, Sara Faggian, Antonio Paoli, Giuseppe Marcolin","doi":"10.1152/japplphysiol.00695.2024","DOIUrl":"10.1152/japplphysiol.00695.2024","url":null,"abstract":"<p><p>This study investigated whether a 4-wk training on an easy-level (EL) unstable board could induce a transfer of balance performance in a hard-level (HL) unstable board and in an unexpected perturbation-based task. Nonlinear center of pressure (CoP) analysis investigated whether training could induce postural control adaptations in trained and untrained tasks. Thirty-four subjects were divided into a training (TR, <i>N</i> = 17) group and a control (CTRL, <i>N</i> = 17) group. Balance was assessed before (T₀) and after (T₁) a balance training under static and dynamic conditions (EL, HL, and perturbation-based task). A force platform allowed the calculation of CoP displacement while balance performance based on the angular displacement of the unstable boards was assessed with an inertial sensor. From the angular displacement, we calculated three parameters of balance performance: full balance (FB), fine balance (FiB), and gross balance (GB). Stabilogram diffusion analysis (SDA) and sample entropy (SampEn) indirectly assessed neuromuscular control mechanisms. Results showed improvements in the TR from T₀ to T₁ in balance performance for FB (<i>P</i> < 0.001), FiB (<i>P</i> < 0.05), and GB (<i>P</i> < 0.01) on EL and HL boards. In the perturbation-based task, the earliest CoP response consequent to perturbation improved after training (<i>P</i> < 0.01). SampEn and SDA revealed increased automaticity (<i>P</i> < 0.05) and efficiency (<i>P</i> < 0.05) of balance control in the EL and HL tasks after training. Balance training led to highly task-specific adaptations and improvements that can be transferred between functionally similar balance tasks. Postural strategies learned during training seemed barely transferable to a different balance task, as the unexpected perturbation of the base of support.<b>NEW & NOTEWORTHY</b> Our study showed that improvement in balance performance is task-specific, with transfer depending on functional similarities between the trained and the untrained tasks. Computational nonlinear methods highlighted that training could extend the improved efficiency and automaticity of balance control of the trained task to a similar untrained task. Therefore, the benefits of balance training may not generalize to all balance challenges, highlighting the importance of targeted testing and training approaches.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"761-773"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143491552","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 legacy of The John B. Pierce Laboratory.","authors":"Nina S Stachenfeld, Loretta DiPietro","doi":"10.1152/japplphysiol.00999.2024","DOIUrl":"10.1152/japplphysiol.00999.2024","url":null,"abstract":"","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":"138 3","pages":"651"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143468267","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 condensed heat acclimation on thermophysiological adaptations, hypoxic cross-tolerance, exercise performance, and deacclimation.","authors":"Charlotte E Stevens, Joseph T Costello, Michael J Tipton, Ella F Walker, Alex A M Gould, John S Young, Ben J Lee, Thomas B Williams, Fiona A Myers, Jo Corbett","doi":"10.1152/japplphysiol.00775.2024","DOIUrl":"10.1152/japplphysiol.00775.2024","url":null,"abstract":"<p><p>Short duration heat acclimation (HA) (≤5 daily heat exposures) elicits incomplete adaptation compared with longer interventions, possibly due to the lower accumulated thermal \"dose.\" It is unknown if matching thermal \"dose\" over a shorter timescale elicits comparable adaptation to a longer intervention. Using a parallel-groups design, we compared: <i>1)</i> \"condensed\" HA (CHA; <i>n</i> = 17 males) consisting of 4 × 75 min·day^-1 heat exposures [target rectal temperature (<i>T</i>_rec) <i>=</i> 38.5 °C] for two consecutive days, with <i>2)</i> \"traditional\" HA (THA; <i>n</i> = 15 males) consisting of 1 × 75 min·day^-1 heat exposure (target <i>T</i>_rec = 38.5°C) for eight consecutive days. Physiological responses to exercise heat stress, hypoxia, and normoxic exercise performance were evaluated pre- and postintervention. Thermal (<i>T</i>_rec over final 45 min: CHA = 38.45 ± 0.17°C, THA = 38.53 ± 0.13°C, <i>P</i> = 0.126) and cardiovascular strain were not different during interventions, indicating similar thermal \"dose,\" although CHA had lower sweating rate, higher starting <i>T</i>_rec, and greater inflammation, gastrointestinal permeability, and renal stress (<i>P</i> < 0.05). However, CHA elicited an array of thermophysiological adaptations that did not differ from THA [reduced indices of peak thermal (e.g., Δ peak <i>T</i>_rec CHA = -0.28 ± 0.26°C, THA = -0.36 ± 0.17°C, <i>P</i> = 0.303) and cardiovascular strain, inflammation, and renal stress; blood and plasma volume expansion; improved perceptual indices], although improvements in resting thermal strain (e.g., Δ resting <i>T</i>_rec CHA = -0.14 ± 0.21°C, THA = -0.35 ± 0.29°C, <i>P</i> = 0.027) and sweating rate were less with CHA. Both interventions improved aspects of hypoxic tolerance, but effects on temperate normoxic exercise indices were limited. The diminished thermal strain was well-maintained over a 22-day decay period. In conclusion, CHA could represent a viable acclimation option for time-restricted young healthy males preparing for a hot, and possibly high-altitude, environment.<b>NEW & NOTEWORTHY</b> This study has shown, for the first time, that a novel condensed heat acclimation program can elicit an array of thermophysiological adaptations, many of which do not differ from traditional heat acclimation. These findings suggest that accumulated thermal \"dose\" is an important factor contributing to the adaptive responses to heat stress and that condensed heat acclimation may represent a viable option for time-restricted individuals (e.g., military personnel, firefighters, and athletes) preparing to enter a hot environment.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"634-650"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143006000","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":"Low-intensity activity breaks combined with alternate day interval training mitigate cardiovascular effects of sedentary behavior.","authors":"Courtney R Chang, Angelo Sabag, Monique E Francois","doi":"10.1152/japplphysiol.00484.2024","DOIUrl":"10.1152/japplphysiol.00484.2024","url":null,"abstract":"<p><p>This study aimed to determine whether interrupting prolonged sitting with brief bouts of light-intensity activity (ISIT), undertaking structured high-intensity interval training (HIIT), or the combination of both interventions would elicit greater cardiometabolic benefits. Seventeen healthy adults (22-50 yr) were recruited to undertake three 2-wk interventions in a random order: <i>1</i>) HIIT (6 HIIT sessions + <5,000 steps following the session and on the next day), <i>2</i>) ISIT (2.5-min light-intensity walking every hour for 12 h/day on weekdays), and <i>3</i>) HIIT + ISIT. Participants underwent a 6-day lead-in phase prior to each condition (<i>days 1-3</i>: normal activity, <i>days 4-6</i> sedentary: <5,000 steps/day). Pre- and postassessments included glycemic control (2-h postprandial glucose), endothelial function via flow-mediated dilation (FMD), cardiorespiratory fitness, and body composition. Changes in primary and secondary outcomes were assessed via repeated measures ANOVA. Eleven participants completed all conditions (8 female, 33 ± 5 yr, 23 ± 4 kg/m², habitual activity 7,156 ± 2,272 steps/day). FMD significantly improved following HIIT + ISIT when compared with ISIT (+1.04 ± 1.20%, <i>P</i> = 0.02), but there were no differences when ISIT was directly compared with HIIT. Cardiorespiratory fitness improved significantly following HIIT + ISIT when compared with ISIT (+1.88 ± 2.03 mL/kg/min, <i>P</i> = 0.01), but there were no differences when ISIT alone was compared with HIIT. There were no significant differences between groups for outcomes related to glucose control or body composition. HIIT + ISIT elicits greater improvements in cardiovascular outcomes when compared with ISIT but not HIIT. The benefits of structured exercise, such as HIIT, may go beyond those achieved by limiting sedentary behavior alone.<b>NEW & NOTEWORTHY</b> Although the adverse health effects of sedentary behavior are well-recognized, effective strategies for interrupting such behavior remain unclear. This study demonstrates that combining light-intensity activity breaks throughout the day with structured high-intensity exercise every other day can mitigate some of the cardiovascular consequences associated with prolonged sedentary periods in healthy young adults. Furthermore, our findings also suggest that merely incorporating regular breaks of light-intensity activity may not suffice. These results underscore the importance of regular exercise for cardiovascular health amid sedentary lifestyles.</p>","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"799-809"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143065882","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":"Manuscript writing for dummies: like sands through the hourglass.","authors":"W Larry Kenney","doi":"10.1152/japplphysiol.00842.2024","DOIUrl":"10.1152/japplphysiol.00842.2024","url":null,"abstract":"","PeriodicalId":15160,"journal":{"name":"Journal of applied physiology","volume":" ","pages":"718-719"},"PeriodicalIF":3.3,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143006011","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}