Frontiers in Physiology最新文献

{"title":"The effects of acute and chronic exercise on immune markers of TH1/TH2 cells in older adults: a systematic review.","authors":"Thiago Henrique Teodoro, Katerine Palharini Manfrin Costa, Jonato Prestes, José Campanholi, James Navalta, Guilherme Borges Pereira","doi":"10.3389/fphys.2025.1453747","DOIUrl":"10.3389/fphys.2025.1453747","url":null,"abstract":"<p><strong>Purpose: </strong>Imbalance between Th1 and Th2 cells correlated with increased disease incidence, is well-documented in the older adult. Both acute and chronic exercise induce a transient shift in organic homeostasis, modulating the immune system and impacting the balance between Th1 and Th2 cells. This review investigates the impact of acute and chronic exercise on immune markers of Th1 and Th2 cells in the older adults.</p><p><strong>Methods: </strong>This study was conducted as a systematic review, following PRISMA guidelines, databases including PubMed, Web of Science, Embase, Science Direct, and Scopus were searched until March 2024, identifying randomized controlled trials and prospective observational studies that examined the effects of acute and chronic exercise on intracellular and surface markers, cytokines, and immunoglobulins in older adults. Studies involving animal subjects, isolated cells, diseased patients, or exposure to medications and drugs were excluded. The quality of the selected studies was assessed using the Cochrane risk of bias tool (ROB2), with data organized and presented in tables and figures.</p><p><strong>Results: </strong>Fourteen studies with 525 participants were included in the analysis. An acute session significantly increased serum IL-4, IL-6, and IL-10 levels immediately afterward, returning to baseline within 1 hour at moderate to high intensities. Chronic exercise at moderate to high intensities reduced serum TNF-α, IL-6, and the CD4/CD8 ratio, while increasing IL-10 levels after 24 weeks. Intracellular, other surface markers and cytokines, and immunoglobulins were not analyzed.</p><p><strong>Conclusion: </strong>Chronic exercise decreases serum TNF-α and IL-6 levels, lowers the CD4/CD8 ratio, and increases IL-10 after 24 weeks, aiding Th1 and Th2 balance. Acute exercise temporarily increases serum IL-4, IL-6, and IL-10 levels, returning to baseline within an hour, indicating short-term immune modulation of Th1/Th2 balance.</p><p><strong>Systematic review registration: </strong>https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021244426, Identifier CRD42021244426.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"16 ","pages":"1453747"},"PeriodicalIF":3.2,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11850391/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143498933","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":"Within- and between-day test-retest reliability of responses to rapid bilateral anterolateral magnetic phrenic nerve stimulation in healthy humans (ReStim).","authors":"Kyle G P J M Boyle, Andrea A Beglinger, Heinrich Häusler, Anna Stahel, Esther I Schwarz, Christina M Spengler","doi":"10.3389/fphys.2025.1481766","DOIUrl":"10.3389/fphys.2025.1481766","url":null,"abstract":"<p><strong>Background: </strong>Mechanical ventilation can lead to lung injury and diaphragmatic dysfunction. Rapid bilateral anterolateral magnetic phrenic nerve stimulation (rBAMPS) may attenuate both of the aforementioned issues by inducing diaphragm activation. However, in order for rBAMPS to become part of standard of care, the reliability of inspiratory responses to rBAMPS needs to be established.</p><p><strong>Methods: </strong>Eighteen healthy participants (9F) underwent five blocks of 1-s rBAMPS at 25 Hz starting at 20% of maximal stimulator output with 10% increments. Three blocks were completed on the same day to test within-day reliability, and two additional blocks were each completed on subsequent days to test between-day reliability. Mean transdiaphragmatic pressure (P_di,mean), tidal volume (V_T), discomfort, pain, and paresthesia were recorded for each rBAMPS. Relative and absolute reliability of both P_di,mean and V_T were quantified by calculating intraclass correlation coefficients (ICC) and standard error of measurements (SE_M), respectively. An ordinal regression was used to determine changes of sensory ratings within and between days.</p><p><strong>Results: </strong>At all stimulator outputs, within-day P_di,mean displayed \"good\" reliability (ICC range 0.78-0.89). Between days, P_di,mean reliability was also \"good\" (ICC range 0.79-0.87) at stimulator outputs of 20%-50% of maximum, but \"moderate\" (ICC range 0.56-0.72) at stimulator outputs of 60%-100%. SE_M for P_di,mean within day ranged from 0.9 to 3.4 across tested stimulator outputs and increased on average by 1.4 ± 0.9 between days. The V_T reliability was \"good\" to \"excellent\" within (ICC range 0.82-0.94) and between (ICC range 0.81-0.96) days at all stimulator outputs. SE_M for V_T within day ranged from 0.08 to 0.36 and from 0.11 to 0.30 between days and tended to be larger at stimulator outputs greater than 50% of maximum. Subsequent blocks within day were associated with decreased discomfort and pain (P ≤ 0.043), while subsequent days were associated with decreased discomfort and paresthesia (P < 0.001).</p><p><strong>Discussion: </strong>rBAMPS appears to induce reliable diaphragmatic contractions, while select sensory responses become blunted over repeated stimulations. However, as reliability is slightly lower between days compared to within day, stimulation parameters may need to be adjusted to achieve similar responses on different days.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"16 ","pages":"1481766"},"PeriodicalIF":3.2,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11850319/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143499339","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":"The physiological responses to volume-matched high-intensity functional training protocols with varied time domains.","authors":"Jessica S Smith, Gabriella F Bellissimo, Fabiano T Amorim","doi":"10.3389/fphys.2024.1511961","DOIUrl":"10.3389/fphys.2024.1511961","url":null,"abstract":"<p><strong>Background: </strong>High-intensity functional training (HIFT) is typically performed with minimal or no rest periods, including \"rounds for time\" (RFT) or \"as many rounds or repetitions as possible\" (AMRAP) design. Alternatively, some HIFT workouts can be performed with prescribed rest intervals (e.g., \"every minute on the minute\" [EMOM]) that may have significant effects on physiological responses.</p><p><strong>Purpose: </strong>To compare the physiological responses between two different HIFT workouts (EMOM and RFT) that were matched for total work volume (TWV).</p><p><strong>Methods: </strong>Twelve trained individuals (six males and six females) performed two HIFT protocols, EMOM and RFT. Both the EMOM and RFT included five rounds of five power cleans, eight kipping pull-ups, six dumbbell thrusters, and ten burpees performed in this order. Measurements of heart rate (HR), oxygen consumption (VO₂), rating of perceived exertion (RPE) (1-10 scale), blood lactate (BLA), creatine kinase (CK), excess post-exercise oxygen consumption (EPOC), and muscle oxygen saturation (SmO₂) were performed.</p><p><strong>Results: </strong>Time domains were significantly different for the EMOM and RFT workouts (20 vs. 12 min ± 3 min, <i>p</i> < 0.00). There were significant differences between the EMOM and RFT for HR (153 ± 19 bpm vs. 171 ± 12 bpm, <i>p</i> < 0.01), VO₂ (30.8 ± 3 mL/kg/min vs. 38.1 ± 5 mL/kg/min, <i>p</i> < 0.00), RPE (4 ± 1 vs. 7 ± 1, <i>p</i> < 0.00), and EPOC-AUC (3.5 ± 1.2 mL/kg/min vs. 5.0 ± 1.3 mL/kg/min, <i>p</i> < 0.00); however, there were no significant differences in mean SmO₂ (<i>p</i> = 0.44). An interaction effect revealed that BLA was lower for the EMOM (6.5 ± 2.7 mmol/L) than the RFT (11.2 ± 2.1 mmol/L) post-exercise (<i>p</i> < 0.00). Conversely, there was no interaction effect for CK (<i>p</i> < 0.16), yet a significant increase was observed from pre- to post-exercise for both the EMOM and the RFT (<i>p</i> < 0.01).</p><p><strong>Conclusion: </strong>The RFT induced greater physiological stress than the EMOM, indicating that prescribed rest intervals significantly affect the metabolic, cardiovascular, and perceptual responses during high-intensity functional exercise. Furthermore, the RFT may provide a greater cardiorespiratory stimulus, while the EMOM may be more suitable for technique development and recovery in trained individuals.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"15 ","pages":"1511961"},"PeriodicalIF":3.2,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11850382/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500335","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":"An overview of hereditary spherocytosis and the curative effects of splenectomy.","authors":"Kyril Turpaev, Elizaveta Bovt, Soslan Shakhidzhanov, Elena Sinauridze, Nataliya Smetanina, Larisa Koleva, Nikita Kushnir, Anna Suvorova, Fazoil Ataullakhanov","doi":"10.3389/fphys.2025.1497588","DOIUrl":"10.3389/fphys.2025.1497588","url":null,"abstract":"<p><p>Hereditary spherocytosis is a common hemolytic anemia with different severity. The causes of hereditary spherocytosis are mutations in genes that encode red blood cell (RBC) membrane and cytoskeletal proteins, including ankyrin-1, Band 3 (or AE1), α spectrin, β spectrin, and protein 4.2. Molecular defects in these proteins decrease membrane integrity, leading to vesiculation, decreased membrane surface area, and reduced deformability of the cells. Eventually, this leads to the trapping the abnormal RBCs (spherocytes) in the spleen. In most severe cases, splenectomy may be necessary to prevent general RBC collapse during the passage of RBCs through the narrow slits of venous sinuses in the spleen. The clinical benefit of splenectomy results from elimination the primary site of RBC damage and destruction. Splenectomy is a curative approach but can cause complications and should be undertaken after examination by various laboratory approaches. Splenectomy does not correct most genetically determined membrane abnormalities in erythrocytes in patients with hereditary spherocytosis. The transformation of biconcave erythrocytes into spherocytes continues, although to a lesser degree than before surgery. Nevertheless, splenectomy increases the lifespan of red cells, significantly reducing the severity of anemia and improving many physiological signs of HS.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"16 ","pages":"1497588"},"PeriodicalIF":3.2,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11850534/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500337","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":"Glucoraphanin conversion into sulforaphane and related compounds by gut microbiota.","authors":"Tetiana R Dmytriv, Oleh Lushchak, Volodymyr I Lushchak","doi":"10.3389/fphys.2025.1497566","DOIUrl":"10.3389/fphys.2025.1497566","url":null,"abstract":"<p><p>Glucosinolate glucoraphanin, common in cruciferous vegetables, is a biologically stable precursor of isothiocyanates, such as sulforaphane and erucin, potent activators of Nrf2 signaling coordinating an adaptive response to oxidative stress. Sulforaphane is formed by the hydrolysis of glucoraphanin by a plant enzyme called myrosinase, which is inactivated in the stomach of mammals. Since the latter do not have enzymes possessing myrosinase-like activity, glucoraphanin can be metabolized by the gut microbiota, to sulforaphane, sulforaphane-nitrile, glucoerucin, erucin, and erucin-nitrile. Emerging evidence suggests that variations in gut microbiota composition significantly influence the efficiency and outcome of glucoraphanin metabolism, while sulforaphane itself may reciprocally modulate gut microbiota composition and functionality. This review examines the bidirectional interactions between glucoraphanin, sulforaphane, and gut microbiota. We assume that sulforaphane alleviates intestinal inflammation and oxidative stress maintaining intestinal homeostasis and gut barrier integrity. Besides, the role of sulforaphane in breaking the vicious cycle of oxidative stress and gut dysbiosis is reported, demonstrating the potential of dietary isothiocyanates to support gut barrier function.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"16 ","pages":"1497566"},"PeriodicalIF":3.2,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11847849/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143491488","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":"The effects of circuit hydraulic weight interval training on body composition and progression of resistance in recreationally exercising pre- and postmenopausal women: an 18-week quasi-experimental study.","authors":"Małgorzata Socha, Paulina Ćwieląg, Waldemar Andrzejewski","doi":"10.3389/fphys.2025.1540983","DOIUrl":"10.3389/fphys.2025.1540983","url":null,"abstract":"<p><strong>Background: </strong>The lack of physical activity, stress, and unhealthy eating habits contribute to body mass disorders, which form the basis of most civilization diseases. Mature women are increasingly turning to fitness clubs to improve their physique and protect themselves from diseases and the progressive aging process. The multitude of training systems proposed to women by fitness clubs leads to the search for solutions that will bring positive health results. The response to an exercise stimulus may depend on the menopausal status.</p><p><strong>Methods: </strong>This quasi-experimental study aimed to determine the effects of 6, 12, and 18 weeks of circuit hydraulic weight interval training (CHWIT) on anthropometric indices, body composition estimated by the bioelectrical impedance analysis (BIA), and muscle performance in inactive pre- and post-menopausal women from an urban population. A total of 100 women aged between 35 and 69 (mean 51.5 ± 9.61) years with a mean body mass index (BMI) of 27.3 (±5.4 kg/m²) were divided by menopausal status and assigned to the training CHWIT group (25 pre- and 25 postmenopausal women) and the control group (25 pre- and 25 postmenopausal women). Each participant from the CHWIT group took part in a total of 54 training sessions, developed for the Mrs.Sporty network, under the constant supervision of a qualified trainer.</p><p><strong>Results: </strong>After 18 weeks of training in both intervention groups, ANCOVA demonstrated statistically significant (<i>p</i> < 0.05) decreased body fat (%), reduced thigh and arm circumference, and increased muscle component (kg) as the main part of fat-free body mass. Additionally, premenopausal women decreased their body mass, BMI, and waist and hip circumferences. A significant increase in the muscle component was noticed after 6 weeks of CHWIT in pre-menopausal women and only after 18 weeks in postmenopausal women. Significant progression of resistance (amount of repetitions on hydraulic machines) was observed after 6 weeks and at each subsequent stage of CHWIT in both intervention groups (<i>p</i> < 0.001). No significant differences were found in the controls.</p><p><strong>Conclusion: </strong>CHWIT is an effective form of training, improving body composition and physical functions in inactive pre- and postmenopausal women. Changes in the muscle component require a longer intervention of physical effort in women after menopause.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"16 ","pages":"1540983"},"PeriodicalIF":3.2,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11847869/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143491489","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":"Cerebrovascular ageing: how zebrafish can contribute to solving the puzzle.","authors":"Guy Malkinson, Catarina M Henriques","doi":"10.3389/fphys.2025.1548242","DOIUrl":"10.3389/fphys.2025.1548242","url":null,"abstract":"<p><p>The mean life expectancy continues to increase world-wide. However, this extended lifespan trend is not accompanied by health span, or years of healthy life. Understanding the fundamental mechanisms responsible for the switch from health to morbidity with ageing are key to identifying potential therapeutic targets to decrease age-associated morbidity and increase years spent in good health. The leading cause of morbidity in Europe are diseases of the circulatory system and diseases of the nervous system and cognitive disorders are among the top-ten. Cerebrovascular ageing is therefore of particular importance as it links circulatory disease to brain functions, cognition, and behavior. Despite major progress in brain research and related technologies, little is known on how the cerebrovascular network changes its properties as ageing proceeds. Importantly, we do not understand why this is different in different individuals in what concerns rate of dysfunction and its downstream impact on brain function. Here we explore how the zebrafish has evolved as an attractive complementary ageing model and how it could provide key insights to understanding the mechanisms underlying cerebrovascular ageing and downstream consequences.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"16 ","pages":"1548242"},"PeriodicalIF":3.2,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11849178/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143491487","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":"The impact of precompetition state on athletic performance among track and field athletes using machine learning.","authors":"Yuting Zhang, Pengyu Fu, Qi Yu, Qingmei Niu, Dongfeng Nie, Xiangya Dou, Xiaoqin Zhang","doi":"10.3389/fphys.2025.1429510","DOIUrl":"10.3389/fphys.2025.1429510","url":null,"abstract":"<p><strong>Objective: </strong>This study aims to compare the differences in the precompetition status (nutritional, physiological, biochemical, psychological, and sleep statuses) among college track and field athletes with different competition performances and to screen for key indicators of differences affecting athletic performance.</p><p><strong>Methods: </strong>Multiple indicators, traditional methods, and machine learning methods are used to detect the exercise load, fatigue index, and precompetition state of athletes with different sports performances.</p><p><strong>Results: </strong>(1) Two weeks before the competition, the fat mass in the left upper limb in the BP group was significantly higher than that in the BnP group (<i>P</i> < 0.05). The absolute values of blood basophils and triglycerides (TGs) in the BnP group were significantly higher than those in the BP group (<i>P</i> < 0.05). The positive detection rate of urinary leukocytes in the BnP group was higher than that in the BP group, and the positive detection rate of urinary occult blood and vitamin C in the BP group was higher than that in the BnP group. (2) One week before the competition, the blood lactate dehydrogenase (LDH) in the BP group was significantly higher than that in the BnP group (<i>P</i> < 0.05). The detection rate of positive urinary occult blood in the BnP group was higher than that in the BP group (<i>P</i> < 0.05). (3) No significant differences were found in the daily dietary intake, energy consumption values, physical activity, sleep efficiency, real-time heart rate, real-time respiratory rate, and real-time heart rate variability between the intensive and reduced periods. (4) The Rosenberg Self-Esteem Scale score of the BnP group was significantly higher than that of the BP group (<i>P</i> < 0.05).</p><p><strong>Conclusion: </strong>Precompetition absolute basophil, LDH, TG, white blood cells, creatine kinase, fat mass in the left upper limb, erythrocyte pressure (HCT), and individual failure anxiety can be used as training monitoring indicators that focus on tracking athlete status before the race.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"16 ","pages":"1429510"},"PeriodicalIF":3.2,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11842355/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143482698","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":"Work rate adjustments needed to maintain heart rate and RPE during high-intensity interval training in the heat.","authors":"Hillary A Yoder, Anne M Mulholland, Hayley V MacDonald, Jonathan E Wingo","doi":"10.3389/fphys.2025.1506325","DOIUrl":"10.3389/fphys.2025.1506325","url":null,"abstract":"<p><strong>Introduction: </strong>Higher work rates may be sustainable when maintaining target rating of perceived exertion (RPE) compared to maintaining target heart rate (THR) during high-intensity interval training (HIIT) exercise in hot conditions, but may also result in greater thermal strain and cardiovascular drift, as well as greater decrements in maximal oxygen uptake ( <math> <mrow><mover><mi>V</mi> <mo>˙</mo></mover> </mrow> </math> O_2max).</p><p><strong>Purpose: </strong>To test the hypotheses that maintaining target RPE compared to THR during HIIT in the heat results in 1) smaller work rate adjustments, 2) greater thermal and cardiovascular strain, and 3) larger decreases in <math> <mrow><mover><mi>V</mi> <mo>˙</mo></mover> </mrow> </math> O_2max.</p><p><strong>Methods: </strong>Eight adults (4 women) completed a graded exercise test on a cycle ergometer in 22°C and then 4 cycling trials in 35°C, consisting of an 8-min warm-up at 70% maximal heart rate (HR_max) or 12 RPE followed by 1 (15_HR and 15_RPE) or 5 (43_HR and 43_RPE) rounds of HIIT (1 round = 4 min work at 90% HR_max or 17 RPE and 3 min recovery at 70% HR_max or 12 RPE) totaling 15 min or 43 min of exercise, respectively. Each trial ended with a GXT to measure <math> <mrow><mover><mi>V</mi> <mo>˙</mo></mover> </mrow> </math> O_2max.</p><p><strong>Results: </strong>In the 43-min trials work rate decreased from the first to the fifth work interval in both conditions, but by a non-significant, yet moderately larger (ES = 0.53) amount during 43_HR (46 ± 29 W) compared to 43_RPE (30 ± 28 W). From the first to fifth work interval HR increased over time by 12 b⋅min^-1 in 43_RPE (<i>p</i> < 0.001), but did not increase during 43_HR (<i>p</i> = 0.36). Rectal temperature increases were not different between conditions (43_HR = 0.7°C, <i>p</i> < 0.001; 43_RPE = 0.8°C, <i>p</i> < 0.001). <math> <mrow><mover><mi>V</mi> <mo>˙</mo></mover> </mrow> </math> O_2max decreased 15.6% (ES = 0.41) between 15_RPE and 43_RPE (<i>p</i> = 0.005), but it was not different over time during the HR-based trials [6.5%, ES = 0.16 (α adjusted for multiple comparisons = 0.0125) <i>p</i> = 0.03].</p><p><strong>Conclusion: </strong>Maintaining target RPE and THR require considerable declines in work rate during HIIT in the heat, with ∼53% larger declines needed to maintain THR. The mitigation of cardiovascular drift in the THR trial may have contributed to the preservation of <math> <mrow><mover><mi>V</mi> <mo>˙</mo></mover> </mrow> </math> O_2max.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"16 ","pages":"1506325"},"PeriodicalIF":3.2,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11839774/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143467566","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":"The effect of 12-week combined balance and plyometric training on dynamic balance and lower extremity injury risk in college dancers.","authors":"Yuqi Yan, Park Seoyoung, Heo Seomyeong, Yi Zhao","doi":"10.3389/fphys.2025.1501828","DOIUrl":"10.3389/fphys.2025.1501828","url":null,"abstract":"<p><strong>Background: </strong>Dancers face significant physical demands and are at high risk for lower extremity injuries due to the complexity and intensity of their movements, which require strong dynamic balance. Improving dynamic balance through training can potentially enhance performance and reduce injury risk.</p><p><strong>Objective: </strong>This study aimed to investigate the effects of a 12-week combined balance and plyometric training program (BP) compared to plyometric training alone (PL) on dynamic balance and lower extremity injury risk among college dancers.</p><p><strong>Methods: </strong>A total of 30 female college dancers were randomly assigned to either the BP group (n = 15) or the PL group (n = 15). Both groups participated in a 12-week training program, with the BP group engaging in both balance and plyometric exercises, and the PL group performing only plyometric exercises. Dynamic balance was assessed using the Dynamic Posture Stability Index (DPSI). Lower extremity injury risk was evaluated using the Limb Symmetry Index (LSI) and Center of Pressure (COP) measurements, pre- and post-intervention.</p><p><strong>Results: </strong>The BP group showed significant improvements in dynamic balance compared to the PL group, with a reduction in DPSI values (DF-DPSI: p < 0.001, partial η² = 0.625; DL-DPSI: p < 0.001, partial η² = 0.559). Additionally, the BP group showed significant reductions in COP displacements, particularly in the anterior-posterior direction (DF-COPAP: p < 0.015, partial η² = 0.101; DL-COPAP: p = 0.019, partial η² = 0.094). The BP group also demonstrated greater improvements in LSI-3C and LSI-6, which reflect dynamic stability (LSI-3C: p < 0.001, partial η² = 0.229; LSI-6: p = 0.006, partial η² = 0.128).</p><p><strong>Conclusion: </strong>The 12-week combined balance and plyometric training program was more effective than plyometric training alone in improving dynamic balance and reducing lower extremity injury risk in college dancers. This combined training approach is recommended for improving performance and preventing injuries in dancers.</p>","PeriodicalId":12477,"journal":{"name":"Frontiers in Physiology","volume":"16 ","pages":"1501828"},"PeriodicalIF":3.2,"publicationDate":"2025-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11851013/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143499021","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}