European Journal of Applied Physiology最新文献

{"title":"Unraveling the link between resting metabolic rate and phase angle in facioscapulohumeral dystrophy: a comparative and associative analysis.","authors":"Oscar Crisafulli, Renato Baptista, Giorgio Bottoni, Luca Grattarola, Rossella Tupler, Emanuela Lavaselli, Venere Quintiero, Giuseppe D'Antona","doi":"10.1007/s00421-025-05853-8","DOIUrl":"https://doi.org/10.1007/s00421-025-05853-8","url":null,"abstract":"<p><strong>Background: </strong>Resting metabolic rate (RMR) and phase angle (PhA) are muscle-related measures whose relationship has been analyzed in several cohorts. However, such parameters and their association are underexplored in facioscapulohumeral dystrophy (FSHD).</p><p><strong>Methods: </strong>Thirty-nine genetically confirmed and clinically categorized FSHD patients (13 females, 26 males; mean age 37.9 years) and 26 matched healthy controls (HC) were recruited. RMR and PhA were assessed using indirect calorimetry and bioimpedance analysis, respectively. Physical activity level (PAL), as potential confounder, was assessed using the International Physical Activity Questionnaire in HC and a subgroup of 18 patients. Comparative and associative analyses were conducted. For associative analyses, PAL and age were included as covariates, while clinical category [grouping patients into Group 1 (category A, classical phenotype, n = 28) and Group 2 (categories B-D, non-classical phenotypes, n = 11)] and sex were used as stratification factors.</p><p><strong>Results: </strong>Patients showed significantly lower PhA and PAL than HC, but similar RMR. The association was strong in HC, weaker but still significant in the overall FSHD group, and non-significant in the PAL subgroup. As a covariate, PAL weakened the association only in HC, while age weakened the association only in patients. Stratification by sex resulted in loss of significance in both groups, while category stratification showed significant association only in Group 2.</p><p><strong>Conclusions: </strong>While the reduced PhA in FSHD aligns with literature, an RMR comparable to HC contradicts previous findings, suggesting the need for further investigation. Overall, PhA does not emerge as a parameter strongly associated with RMR in patients with FSHD.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144301340","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":"Muscle oxygenation levels in smokers and non-smokers during exercise: insights from a university-based study.","authors":"Buğra Kerget, Büşranur Taşkin, Alperen Aksakal, Hatice Beyza Özkan, Elif Yilmazel Uçar","doi":"10.1007/s00421-025-05829-8","DOIUrl":"https://doi.org/10.1007/s00421-025-05829-8","url":null,"abstract":"<p><strong>Background: </strong>Today, as the age of smoking is decreasing, awareness of the harms of tobacco is still not at a sufficient level among young people. In our study, we aimed to compare the muscle oxygenation levels between students who smoke and those who do not smoke after the training on the harms of tobacco products.</p><p><strong>Methods: </strong>A total of 40 smokers and 30 non-smokers, aged 23 and studying at our university, participated between November 2024 and December 2024. Vastus lateralis muscle oxygenation was measured during the six-minute walking test (6MWT).</p><p><strong>Results: </strong>In smokers, exhaled CO, pulse at the beginning and end of 6MWT, Borg dyspnea, and fatigue scores were significantly higher than in non-smokers (p < 0.001). Maximum and minimum SmO₂ levels measured at the beginning and end of 6MWT were lower in smokers (p < 0.001), while changes in SmO₂ were greater in smokers (p < 0.001). Smoking level negatively correlated with maximum and minimum SmO₂ and positively with ΔSmO₂ (R = - 0.82, p < 0.001; R = 0.83, p < 0.001; R = 0.79, p < 0.001). Similarly, exhaled CO negatively correlated with maximum and minimum SmO₂ and positively with ΔSmO₂ (R = - 0.83, p < 0.001; R = 0.84, p < 0.001; R = 0.78, p < 0.001).</p><p><strong>Conclusion: </strong>Smoking causes a decrease in muscle oxygenation depending on the amount smoked. We believe that this cumulative burden may be a precursor to comorbidities that develop in later ages.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144293559","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":"Equity in training load: research design considerations for intervention assessment in sports science and physical therapy.","authors":"Tomasz Kowalski, Moritz Schumann, Sebastian Klich, Michele Zanini","doi":"10.1007/s00421-025-05844-9","DOIUrl":"https://doi.org/10.1007/s00421-025-05844-9","url":null,"abstract":"<p><p>Training load (TL) assessment and management are important in athletic training, physical therapy, and sports science, as exercise-induced responses to the exercise stimulus depend on the dose of the applied exercise stimulus. Different TL may result in distinct adaptation, intervention feasibility, or injury risks, amongst other considerations. However, often studies are based on interventions with different TL between the groups, possibly influencing the research outcomes. This opinion paper discusses scenarios where TL matching may be beneficial, and presents literature exemplary cases from respiratory muscle training, strength training in endurance athletes, and exercise-based physical therapy. Moreover, the contextual role of TL in different populations and possible solutions regarding study design are discussed. We conclude that the considerations of TL assessment in research design may be beneficial for comparative experimental studies, crossover, and counterbalanced trials in sports sciences and physical therapy. By acknowledging and reconciling TL differences, researchers can elevate the relevance of their findings. Consequently, the effects of an intervention can be attributed to the type of intervention rather than confounded by differences in TL between groups.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144293558","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":"Flight-associated cortisol dynamics and subjective assessments of pain and stress in fighter pilots: an exploratory study.","authors":"Hershel Raff, Keri R Hainsworth, Rachel Cutlan, Katherine A Sherman, Brian D Stemper","doi":"10.1007/s00421-025-05837-8","DOIUrl":"https://doi.org/10.1007/s00421-025-05837-8","url":null,"abstract":"<p><strong>Purpose: </strong>Operating a high-performance fifth-generation fighter jet is a potential stressor in which hypothalamic-pituitary-adrenal (HPA) axis dynamics may reflect the intensity of and adaptation to the stressor. The purpose of this study was to evaluate HPA axis activity in fighter pilots and explore whether indices of activity correlated with subjective indices of stress.</p><p><strong>Methods: </strong>We studied HPA axis dynamics in 20 experienced fifth-generation fighter pilots (18 men/2 women) by measuring salivary cortisol at various times from bedtime the night before a flight training to awakening the morning after the flight training. We also measured plasma ACTH and serum cortisol the day before the flight and immediately following the flight. These findings were correlated with prior pilot flight experience and subjective assessments of pain and stress.</p><p><strong>Results: </strong>Seven (35%) of the pilots demonstrated normal salivary cortisol levels at all time points despite one having a high index of pain. Lower pre-flight salivary cortisol was correlated with more flight hours in the year leading up to the flight exercise. Flight day awakening salivary cortisol was inversely correlated with pilot-reported post-flight stress. In general, there were no other major correlations suggesting a disconnect between an objective measure of stress via HPA axis dynamics and subjective indices of stress and pain.</p><p><strong>Conclusion: </strong>The acute HPA axis response in some experienced fighter pilots habituates to the stressor of flying a fighter jet during a training exercise. The experience of the pilot was a determinant of their HPA axis stress response.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144283104","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":"Resistance exercise and skeletal muscle: protein synthesis, degradation, and controversies.","authors":"Fujue Ji, Hae Sung Lee, Jong-Hee Kim","doi":"10.1007/s00421-025-05832-z","DOIUrl":"https://doi.org/10.1007/s00421-025-05832-z","url":null,"abstract":"<p><p>Maintaining and enhancing skeletal muscle mass and strength are essential for optimizing metabolic function and preventing chronic diseases. Resistance exercise plays a pivotal role in this process by modulating the balance between synthesis and degradation of skeletal muscle protein. While the efficacy of such exercise in stimulating these processes is well established, uncertainties persist regarding the fibre-type specificity and contraction mode-dependent regulation of key signalling pathways, including mTORC1, AMPK, and the ubiquitin-proteasome system. Furthermore, the interplay between metabolic stressors-such as biopsy timing, muscle damage, inflammation, and oxidative stress-and skeletal muscle adaptation remains insufficiently characterized, posing challenges to mechanistic research. To address these gaps, this review systematically synthesizes current evidence on fibre-specific and contraction mode-specific regulation of skeletal muscle protein turnover. We critically examine the influence of these factors on major signalling pathways and muscle adaptation, identifying key areas of uncertainty and methodological limitations in existing studies. Based on these insights, we propose a novel theoretical framework and predictive model to guide future investigations. By providing a comprehensive and mechanistically driven analysis, this review advances the understanding of resistance exercise-induced muscle adaptations and their physiological implications. Our findings offer valuable insights for optimizing exercise strategies and developing targeted interventions for muscle-related conditions, including sarcopenia, cachexia, and metabolic disorders.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144283106","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":"Increased deep muscle activity with interference low-frequency electrical muscle stimulation: evaluation by positron emission tomography.","authors":"Yuichi Nishikawa, Junsuke Nakase, Takuya Sengoku, Seigo Kinuya","doi":"10.1007/s00421-025-05847-6","DOIUrl":"https://doi.org/10.1007/s00421-025-05847-6","url":null,"abstract":"<p><strong>Background: </strong>The effects of electrical muscle stimulation (EMS) devices that efficiently promote deep muscle contraction have not been characterized. The purpose of this study was to clarify using [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) whether interference with low-frequency EMS can promote muscle metabolism in deep.</p><p><strong>Method: </strong>A total of 16 healthy males were randomly assigned to the EMS group (n = 8, age = 29.8 ± 4.1 years) or the control group (n = 8, age = 26.1 ± 5.0 years). Individuals in the EMS group received interference low-frequency EMS for 20 min each day over a span of three consecutive days as part of the pretest phase. On the measurement day, an EMS was conducted for 10 min, followed by an injection of FDG and then another EMS for an additional 10 min. The control group remained in a seated position for 10 min, after which FDG was administered intravenously. Images from PET-computed tomography were acquired in each group 60 min after the injection of FDG. Regions of interest were delineated in each muscle of the lower extremities. We analyzed the metabolism of each skeletal muscle sample by employing a standardized uptake value.</p><p><strong>Results: </strong>Compared with the control group, the EMS group showed increased glucose metabolism in both superficial and deep muscles of the trunk, pelvis, and lower extremities, as measured by FDG uptake.</p><p><strong>Conclusion: </strong>This exploratory study suggests that low-frequency interference EMS may increase glucose metabolism in deep and superficial muscles of the trunk, pelvis, and lower extremities.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144283105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effects of acute and chronic oral tea catechins and ornithine supplementation on exercise-induced ammonia accumulation and cycling performance in healthy young men: a randomized, double-blind, cross-over, placebo-controlled trial.","authors":"Chihiro Nagayama, Yuka Hamada, Kayoko Kamemoto, Takahiro Hasumura, Yoshihiko Minegishi, Yuji Matsui, Noriyasu Ota, Masashi Miyashita","doi":"10.1007/s00421-025-05833-y","DOIUrl":"https://doi.org/10.1007/s00421-025-05833-y","url":null,"abstract":"<p><strong>Purpose: </strong>This study examined the effects of acute and chronic oral intake of tea catechins and ornithine supplementation on exercise-induced ammonia accumulation and cycling performance.</p><p><strong>Methods: </strong>Sixteen healthy young men participated in a randomized, double-blind, cross-over, placebo-controlled study. For the acute trials, the participants consumed either tea catechins and ornithine (CO) or placebo (P) and performed cycling exercises at an intensity corresponding to 75% of the maximum heart rate for 60 min, followed by a 15-min cycling performance test. The participants continued to consume each designated supplement for 13 days. For the chronic trials, the participants repeated the same protocol as the acute trials on day 14. After a washout period, the participants changed the supplement and repeated the same protocol as above.</p><p><strong>Results: </strong>Plasma catechins (acute ES = 3.61; chronic ES = 2.64, p < 0.001) and ornithine (acute ES = 4.28; chronic ES = 2.25, p < 0.001) concentrations were higher in both acute and chronic CO trials than those in P trials. No differences were found in plasma ammonia concentration measured during the whole experimental period and in mean power output during the performance test among trials. Subjective fatigue during 60-min cycling was lower in both acute and chronic CO trials than those in P trials (acute ES = 0.32, chronic ES = 0.60, p < 0.001).</p><p><strong>Conclusions: </strong>A single dose and 14-day oral intake of tea catechins and ornithine supplementation did not suppress exercise-induced ammonia accumulation or enhance cycling performance.</p><p><strong>Clinical trial: </strong>Clinical trial registration ID: UMIN000035267.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144283107","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":"Immediate effects of passive stretching and/or local vibration on ankle range of motion, calf muscle stiffness and passive torque: a randomized controlled cross-over trial.","authors":"Daniel Jochum, Andreas Konrad, Josef Fischer, Stanislav D Siegel, Konstantin Warneke","doi":"10.1007/s00421-025-05839-6","DOIUrl":"https://doi.org/10.1007/s00421-025-05839-6","url":null,"abstract":"<p><strong>Purpose: </strong>Vibrational stimulation was suggested sufficient to acutely enhance range of motion (ROM). However, the actual merit of superimposed vibration and underlying mechanical or sensory mechanisms of ROM increases due to local vibration are not well understood.</p><p><strong>Methods: </strong>Using a randomized controlled cross-over trial, this study opposed two minutes of stretching + vibration (STV) to vibration (V) and stretching (ST) alone as well as a passive control (CG) in 30 healthy, recreationally active participants. Pre- and post-intervention measurements of ankle dorsiflexion ROM, ankle passive torque, and gastrocnemius medialis muscle stiffness were conducted using a dynamometer and shear wave elastography, respectively.</p><p><strong>Results: </strong>All interventions significantly increased ROM (p < 0.001, η² = 0.622) compared to CG, with no additional benefits observed for vibration combined with stretching compared to stretching or vibration alone. However, combining stretching and vibration produced the most pronounced reductions in passive torque over the whole ankle ROM. The combination demonstrated additive effects of stretching and vibration, which affected passive torque in the end ROM and at rest, respectively. Muscle stiffness decreased, but did not differentiate between conditions.</p><p><strong>Conclusion: </strong>These findings negate additional acute vibration effects on ROM that surpass the effects of stretching alone, while the combination of stretching and vibration presented the most prominent influence on passive torque and joint resistance. Vibration also increases stretching pain tolerance; this might facilitate the conduction of exercises and improves compliance as well as adherence to stretching habits.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144274536","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":"Can measurement errors explain variance in the relationship between muscle- and tendon stiffness and range of motion?-a blinded reliability and objectivity study.","authors":"Konstantin Warneke, Julia Meder, Gerit Plöschberger, Manuel Oraže, Maximilian Zechner, Daniel Jochum, Stanislav D Siegel, Andreas Konrad","doi":"10.1007/s00421-025-05814-1","DOIUrl":"https://doi.org/10.1007/s00421-025-05814-1","url":null,"abstract":"<p><strong>Introduction: </strong>The relationship between range of motion (ROM) and underlying parameters such as stiffness (ST) remains controversial throughout the literature. Therefore, this study aimed to analyze the potential role of accumulated measurement errors and subjective influences through a comprehensive assessment of both systematic and random errors on the correlation between tissue ST and ROM.</p><p><strong>Methods: </strong>A total of 75 subjects participated in this double-blinded reliability evaluation. Besides muscle thickness assessments, lower legs' ST in the calf muscle and Achilles tendon (shear-wave elastography [SWE] and viscoelastic parameters [MyotonPRO], respectively) were correlated with ankle dorsiflexion ROM (knee-to-wall test [KtW]).</p><p><strong>Results: </strong>Ultrasound image acquisition (i.e., muscle thickness and ST) and myotonometry showed intrasession reliability (ICC = 0.93-0.99 and 0.72-0.99, respectively) depending on the device. Only for MyotonPRO, there were meaningful systematic and random errors only for decrement (SEM = 0.002-10.629; MAE = 0.01-24.84). ROM showed ICC > 0.99, while for all parameters interday reliability declined (ICC = 0.395-0.88). Interrater objectivity showed ICC = 0.61-0.91 for ultrasound analysis and 0.66-0.96 for myotonometry. No agreement (ICC = 0-0.09) between different ST measurements was observed, while relationship between ST and ROM depended on the investigator (r = 0.21-0.26 versus r = - 0.02--0.07).</p><p><strong>Discussion: </strong>While aligned with reliability and objectivity metrics from the literature, our results demonstrate that ST determination is device-dependent, and its relationship with ROM varies by measurement day and investigator. This underlines clinically relevant measurement errors in ST evaluation, calling for advance standardization to improve reliability and objectivity, while measurement errors quantified beyond the ICC must not be neglected in future studies.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144274535","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":"Internal training exposure: development and construct validation of an individualised method using heart rate variability.","authors":"Samrat Sheoran, Antonis Stavropoulos-Kalinoglou, Josh Darrall-Jones, Dan Weaving","doi":"10.1007/s00421-025-05841-y","DOIUrl":"https://doi.org/10.1007/s00421-025-05841-y","url":null,"abstract":"<p><strong>Purpose: </strong>The aim was to develop and validate an individualised internal training exposure method by deriving weighting factors for each heart rate (HR) from detrended fluctuation analysis of heart rate variability (DFA-α1) during a graded exercise test.</p><p><strong>Methods: </strong>Thirty-seven participants (17 females; 32.72 ± 9.26 years; maximal oxygen uptake, <math><mover><mi>V</mi> <mo>˙</mo></mover> </math> O_2max = 48.32 ± 7.95 mL kg^-1 min^-1) completed a step- and a ramp incremental test to measure blood lactate (BLa), DFA-α1, and cardiorespiratory fitness (CRF) variables, i.e. speed at lactate, ventilatory thresholds (LTs/VTs), and <math><mover><mi>V</mi> <mo>˙</mo></mover> </math> O_2max. Exponential fitting of the fractional elevation of HR (ΔHR) with BLa (individualised training impulse; iTRIMP) or DFA-α1 (αTRIMP) generated individualised coefficients for both methods. The TRIMP weightings were interpolated values of BLa or DFA-α1 derived at each ΔHR through coefficients to represent individualised physiological intensity. Principal component regression evaluated the relationship between combined CRF variables and the TRIMP coefficients or weightings.</p><p><strong>Results: </strong>Large inter-individual variation was observed at the same physiological thresholds (ΔHR at LT₁/VT₁ = 0.51-0.83 and LT₂/VT₂ = 0.63-0.96), underscoring the need for TRIMP methods to weight ΔHR and account for different exposure at similar intensity. CRF had a moderate relationship with coefficients for iTRIMP and αTRIMP methods (R²_average = 0.52-0.67), but a moderate to strong relationship with their weightings at a fixed ΔHR (R²_average = 0.67-0.78).</p><p><strong>Conclusion: </strong>αTRIMP is a valid and practically accessible method for quantifying internal training exposure using ECG-based HR monitors, which individualises physiological intensity through DFA-α1-derived weightings among individuals of varied fitness exercising at same percentages of HR.</p>","PeriodicalId":12005,"journal":{"name":"European Journal of Applied Physiology","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144265696","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}