Search Results (467)

Exercise performance is a critical trait for evaluating the economic and breeding value of working and athletic horses, with cardiac structure and function serving as essential physiological determinants of athletic capacity. This study aimed to investigate the multi-omics response mechanisms associated with varying degrees of cardiac remodeling under identical exercise intensity. Twenty 2-year-old Yili horses were selected and categorized based on echocardiographic parameters into a high cardiac remodeling group (BH; EDV > 500 mL, SV > 350 mL, EF > 66%) and a low cardiac remodeling group (BL; EDV < 450 mL, SV < 330 mL, EF < 64%). Blood samples were collected before and after the 1000 m constant-speed test (pre-test high cardiac remodeling group (BH, n = 10), post-test high cardiac remodeling group (AH, n = 10), pre-test low cardiac remodeling group (BL, n = 10), post-test low cardiac remodeling group (AL, n = 10)), and integrated metabolomic, transcriptomic, and miRNA profiling were conducted to systematically characterize molecular responses to exercise-induced stress. Metabolomic analysis identified a total of 1936 lipid metabolites, with the BH group exhibiting stronger post-exercise lipid mobilization and significant enrichment of sphingolipid signaling pathways. Transcriptomic and miRNA analyses further revealed that key miRNAs in the BH group, including miR-186, miR-23a/b, and the let-7 family, along with their target genes (e.g., GNB4, RGS5, ALAS2), were involved in fine regulation of cardiac electrophysiology, oxidative stress, and energy metabolism. Integrated analysis indicated that the AH vs. BH comparison uniquely enriched pathways related to glycine-serine-threonine metabolism and glycosylphosphatidylinositol (GPI)-anchor biosynthesis, whereas the AL vs. BL comparison showed unique enrichment of α-linolenic acid and arachidonic acid metabolism pathways. Ultimately, multi-omics integration identified that in the BH group, eca-let-7d, eca-let-7e, eca-miR-196b, eca-miR-2483, and eca-miR-98 regulate ALAS2 and, together with GCSH, influence the enrichment of lipids such as PS(17:0_16:1), PS(18:0_18:1), and PS(20:0_18:1). These lipids participate in glycine, serine, and threonine metabolism through complex pathways, collectively modulating energy supply, inflammatory responses, and muscle function during exercise. This study reveals the molecular mechanisms by which horses with high cardiac remodeling maintain energy homeostasis and myocardial protection during exercise. Full article

Auxetic structures, characterized by a negative Poisson’s ratio and unique form-fitting deformation, are adopted for designing a bra pad that would facilitate bras with a flexible and adaptive fit. This study compares the pressure distribution between auxetic and traditional molded bra pads, highlighting the advantages of auxetic materials in applying uniform pressure and addressing health concerns. Seven athletic female participants with a bra size of 75B comprise the study sample. Anthropometric data of naked breasts are collected by using three-dimensional (3D) scanning to obtain the underbust and full bust dimensions in the standing and leaning forward positions, while the pressure distribution is measured with the Novel Pliance^® pressure measurement system in three poses: standing, static cycling, and dynamic cycling. The results show that the auxetic designs of bra pads consistently apply a more uniform pressure distribution compared to traditional foam pads, with mean pressures of 2.92 kPa for auxetic pads compared to 4.81 kPa for traditional foam pads during static cycling. Moreover, auxetic pads reduced maximum pressure by 25% compared to molded cups, and spatial variability was halved (SD 0.85 kPa vs. 1.70 kPa). Notably, at the bra neckline, auxetic pads exhibit increased pressure as the body leans forward, demonstrating their ability to adapt to changing breast shapes while maintaining adequate bra-breast contact. In contrast, in the lower breast area, the auxetic pads show a decrease in pressure, which indicates their capacity to accommodate variations in breast girth or volume without exerting excessive force. These findings highlight the superior adaptability and wear comfort provided by an auxetic structure, which shows its potential to address the dynamic support needs of active women. Overall, the auxetic designs of a bra pad in this study represent a significant advancement in sports bra technology and offer a promising alternative to traditional molded cups in activewear design. Full article

Near-Infrared Spectroscopy (NIRS) is a noninvasive technology used to monitor muscle oxygenation in sports science. Since its introduction in 1977, NIRS has evolved into a valuable tool for assessing physiological responses during exercise and rehabilitation. The history of NIRS dates back to early hemoglobin studies in the 19th century, with significant advancements in pulse oximetry during World War II. By the late 1980s, NIRS had become widely used in sports science, allowing researchers to evaluate muscle perfusion and metabolic thresholds in various activities. NIRS applications in sports include determining exercise thresholds, monitoring muscle oxygenation during training, assessing asymmetries between limbs, and evaluating mitochondrial capacity. Studies have explored its use in both team and endurance sports, highlighting its role in optimizing performance and preventing injuries. Beyond sports, NIRS technology is expanding into clinical fields, aiding in rehabilitation and patient monitoring. This critical review has identified several key areas for future research, including the need to clarify methodological influences, strategies to minimize the impact of adipose tissue on NIRS measurements, the importance of conducting longitudinal studies, increased research on sex-specific effects, and a greater emphasis on field-based studies. With continued advancements, NIRS is expected to further enhance our understanding of muscle physiology and human performance, making it a crucial tool in athletic performance assessment and clinical practice. Full article

Background and Objectives: In modern soccer, players frequently perform curved sprinting (CS) actions that combine speed, agility, and neuromuscular control, highlighting the importance of assessing CS performance in youth athletes. This study aimed to investigate age-related differences in CS performance and its relationship with key components of physical fitness—including aerobic capacity, vertical jump height, and agility-based field tests—in U14 and U16 male soccer players. Materials and Methods: A total of 76 registered players participated, evenly divided between the two age groups. Statistical analyses included t-tests, correlation, and regression modeling to determine key predictors of curve-sprint performance. Results: U16 players showed significant between-group differences, with faster CS times on both the good and weak sides (p < 0.001, d = 0.93–1.08), as well as superior performance in the countermovement jump (p < 0.001, d = 1.12), Illinois Agility Test (p < 0.01, d = 0.70), and 5-0-5 change-of-direction (COD) test (p < 0.01, d = 0.74). Significant negative correlations were found between CMJ height and CS times (r = –0.40 to –0.73), indicating that greater explosive power was associated with better CS performance. Moderate to very strong positive correlations were observed between CS and agility measures (r = 0.43 to 0.79), particularly in the U16 group, whereas VO₂max showed no meaningful relationship with CS performance (r = –0.16 to –0.30, p > 0.05). Conclusions: These results suggest that CS may serve as an indicator of neuromuscular power and agility, both of which improve with age. From a practical perspective, regular curve-sprint assessments and multidirectional drills may support talent development by helping coaches monitor neuromuscular efficiency and movement coordination in young players. Full article

Background: Accurate assessment of aerobic capacity is essential for performance monitoring in masters athletes, particularly in high-intensity team sports. The objective of this study was to evaluate the validity and agreement of three indirect maximal oxygen uptake (VO₂max) protocols (Åstrand–Ryhming, YMCA, and Polar OwnIndex Fitness test) against the gold-standard cardiopulmonary exercise testing (CPET) in masters basketball players. Methods: A cross-sectional comparative study included 50 male masters basketball players (aged 51–81 years, M = 64.3 ± 7.9). Validity was determined by comparing results from the three indirect protocols to direct VO₂max measurement via CPET. Agreement was assessed using Pearson correlations (r), systematic error, mean absolute error (MAE), and Bland–Altman limits of agreement. Results: The Åstrand–Ryhming test and YMCA tests showed the closest agreement with CPET (systematic error < 4%, MAE ≈ 17–18%, r > 0.50). The Polar OwnIndex test substantially overestimated VO₂max (mean error ≈ 30%, MAE = 32%). The Åstrand–Ryhming test at low workload yielded the strongest correlation (r = 0.75). Conclusions: The Åstrand–Ryhming and YMCA submaximal tests demonstrated acceptable validity and low systematic bias for estimating VO₂max in masters basketball players, positioning them as practical alternatives to CPET. Conversely, the Polar OwnIndex test showed poor agreement and clinically significant overestimation. These findings support the use of submaximal cycling protocols for fitness monitoring and tailored training prescription in this specific older athlete population. Future longitudinal research is warranted to confirm their ability to track fitness changes over time in this population. Full article

Background: A sexually active lifestyle is generally associated with positive effects on physical condition and health. However, engaging in sexual activity prior to a sports competition could affect athletic performance. This systematic review examines the current literature on the impact of pre-exercise sexual activity on sports performance, with particular attention paid to its effects on physiological, hormonal, cognitive, and perceptual markers. Method: Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we systematically reviewed original studies published within the last 25 years. Eligible studies were randomized or non-randomized controlled design and indexed on PubMed, Scopus, Dialnet, and Cochrane. Additional sources were consulted including a network diagram with Connected Papers^®. Two methodological quality scales, McMaster University Occupational Therapy Evidence-Based Practice Research Group and Physiotherapy Evidence Database (PEDro), were used. The study was registered in PROSPERO (#CRD42023426555). Results: A total of 244 records were identified through the search process, of which 7 studies met the inclusion criteria. The studies involved 117 (115 men) physically and sexually active subjects including 29 elite top athletes. When comparing the sexual activity condition/group (SexG) to abstinence (AbsG), significant (p < 0.05) decreases were observed in average speed and maximum strength. In contrast, non-significant trends towards improvement (p > 0.05) were observed in exercise capacity, reaction time, and muscular endurance. No significant changes (p > 0.05) were found in physiological and hormonal biomarkers and fatigue perception. However, perceived exertion was significantly higher (p < 0.05) in SexG compared to AbsG. Conclusions: Current evidence does not conclusively support the influence of pre-exercise sexual activity on sports performance, or physiological and hormonal biomarkers. However, it could contribute to increased perception of exercise intensity. Full article

Hyrox© is a hybrid competition that is gaining prominence in the competitive field due to its physical demanding nature and broad appeal to athletes from various backgrounds. Understanding athlete profiles and performance determinants in these events is essential to optimize training and recovery strategies. Objectives: This study aimed to examine and describe the profile of athletes participating in Hyrox© competitions, focusing on variables related to their sports background, training habits, recovery strategies, physical capacities, and motivational aspects. Methods: A descriptive analysis was conducted using an ad hoc questionnaire fulfilled by 80 active Hyrox© athletes. The questionnaire addressed aspects such as training frequency and structure, previous athletic experience, strength and endurance levels, recovery practices, and personal goals. Results: The findings revealed a predominantly male athlete profile with high physical demands and prior experience in functional or endurance-based sports. Participants generally exhibited well-developed strength and endurance capacities. However, recovery strategies were often unstructured or insufficient, potentially compromising performance and increasing injury risk. Conclusions: Athletes competing in Hyrox© share characteristics with those in other high-intensity or hybrid modalities, including strong aerobic and anaerobic capacities. Nonetheless, a gap remains in the implementation of structured recovery protocols. These results highlight the need to incorporate comprehensive recovery strategies alongside physical preparation to optimize performance and athlete longevity in hybrid events. Full article

Background/Objectives: There is a sudden and noticeably increasing focus on naturally found antiplatelet inhibitors that humans can use habitually. Given that athletes receive annual training with periods of recovery that are not always suitably adapted to the workload, this study aimed to explore the association between dietary fat intakes and the indices of blood profiles, concentrating on platelet variables in a sample of high-performance athletes. Methods: The sample encompassed 19.8 ± 2.2-year-old Lithuanian high-performance athletes (n = 82). The assessment of the nutritional profile of study participants was performed using a 3-day food record approach. In laboratory settings, the hematology profile of athletes was assessed via the Nihon Khoden automated hematology analyzer. Results: The recorded mean consumption of energy, carbohydrates, protein, and fat in elite athletes was 49 kcal/kg/day, 5.4 g/kg/day, 1.6 g/kg/day, and 40.3% of energy intake (EI), respectively. The study highlighted the excessive consumption of saturated fatty acids (FA) (13.4–14.3% of EI) and dietary cholesterol (698–982 mg/day). Also, considering that the ideal human omega-6 to omega-3 FA ratio is commonly deemed to be between 1:1 and 4:1, an athlete’s ‘Western diet’ was heavily skewed with a ratio fluctuating from 18.9:1 to 19:4 in favor of omega-6 FA. Furthermore, the study found that the outcomes related to slightly higher levels of blood platelet counts and plateletcrit, however, being within normal limits, were associated with a higher intake of omega-6 FA (adjusted odds ratio (AOR) 9.5, 95% confidence interval (CI) 1.2; 9.9, p = 0.029). A higher platelet-to-hemoglobin ratio as a novel indirect blood-based biomarker pronouncing the potential inflammatory processes in the body revealed the reverse relationship of higher intake levels of dietary omega-3 FA (AOR 6.7, 95% CI 1.3; 12.2, p = 0.029), omega-6 FA (AOR 6.2, 95% CI 2.7; 11.5, p = 0.009), and saturated FA (AOR 8.5, 95% CI 1.5; 9.1, p = 0.020) among elite athletes. Conclusions: The prospect of personalized nutrition targeted at the professional athletes’ segment may provide an innovative opportunity to increase athletes’ capacity to manage the platelet function via diet while stressing the importance of further empirical experimental research in this dynamic and vital biomedical field. Full article

Biathlon is a winter Olympic sport that combines high-intensity cross-country skiing with precise rifle shooting. These dual demands require athletes to develop exceptional aerobic capacity while maintaining fine motor accuracy under physiological stress. Despite its complexity, nutritional strategies in biathlon remain under-explored and recommendations are often extrapolated from related endurance sports. This narrative review aims to summarise existing knowledge on nutrition in biathlon, highlight sport-specific challenges and identify areas for future research. The main findings indicate that biathletes face very high energy demands, with daily expenditure exceeding 7000 kcal during intensive training. Carbohydrates are the primary fuel source, with intake recommendations based on training intensity and duration (6–12 g/kg/d). Furthermore, protein is essential for muscle repair, recovery and adaptation. To achieve the recommended intake of 1.6 g/kg/day, it is advisable to consume meals containing approximately 0.3 g/kg of high-quality protein every three to four hours. Given the frequency of training sessions, effective recovery strategies are important in biathlon. When recovery is a priority, biathletes should consume a meal comprising protein (approximately 0.3 g/kg) and carbohydrates (approximately 1.2 g/kg) before key training sessions. Micronutrient and vitamin deficiencies are not commonly observed in biathletes due to their high calorie intake. However, concerns regarding iron and vitamin D are common among endurance athletes due to the high risk of low energy intake, diets lacking in iron, and insufficient exposure to sunlight. On the day of the race, it is recommended that biathletes plan their meals to ensure that they meet their nutritional needs and begin recovery as soon as possible after the race is over. Biathletes may use specific supplements to enhance performance and health during preparation and competition. However, it is important to note that some supplements that improve performance may harm shooting accuracy. Current guidance is provisional, and future research should adopt a dual-performance framework that evaluates both endurance output and shooting precision under realistic competition conditions. Full article

Sleep is a fundamental biological process in athletes, indispensable for tissue regeneration, exercise adaptation, and injury prevention. Disruptions in sleep architecture and duration have been consistently associated with diminished physical performance and adverse health outcomes, impairing muscular strength, power output, and endurance capacity, and concurrently compromising cognitive function. On a physiological level, insufficient sleep disrupts endocrine homeostasis, elevating cortisol levels and reducing anabolic hormones such as testosterone and growth hormone. At the molecular level, sleep loss promotes the upregulation of pro-apoptotic gene expression and exacerbates pro-inflammatory signalling pathways. Optimal sleep duration and quality represent a critical “regenerative window”, essential for enhancing athletic performance and safeguarding physiological resilience. Ensuring adequate sleep among athletes can be effectively achieved through educational, behavioural, and nutritional interventions outlined in this review. Full article

Background: Change-of-direction (CoD) ability is critical in karate, yet sport-specific assessment tools are limited. This study aimed to evaluate the reliability and validity of a newly developed karate-specific CoD test for male and female athletes and to examine its relationships with other motor performance measures. Methods: Thirty-six experienced karatekas (20 men: age 20.8 ± 1.8 years, height 1.79 ± 0.05 m, body mass 73.1 ± 10.6 kg; 16 women: age 21.2 ± 1.7 years, height 1.67 ± 0.04 m, body mass 63.5 ± 8.9 kg), all national squad members, participated. Athletes performed the karate CoD test twice to assess test–retest reliability, and completed additional CoD tests (Y CoD, T-half), linear sprint tests, standing long jump, and Y-balance tests to evaluate criterion validity and associations with other motor abilities. Results: The karate CoD test demonstrated excellent reliability (ICC = 0.996), with similar consistency in men and women. Criterion validity was supported by a meaningful correlation with the Y CoD test, but not with the T-half test. Associations with linear sprinting and lower-limb power (standing long jump) were weak or inconsistent, indicating that karate-specific CoD performance is distinct from general physical capacities. Conclusions: The karate CoD test shows good reliability and validity for assessing planned change-of-direction ability in elite karate athletes. Its use should be limited to pre-planned movements and complemented with other tests (e.g., reactive agility, sprinting, jumping, strength) for a fuller performance assessment. Full article

This study presents a three-dimensional finite element (FE) analysis of the human foot bone structure under mid-stance loading during race walking. A subject-specific biomodel comprising 26 bones and over 40 ligaments was reconstructed from computed tomography (CT) data using Materialise Mimics Research 21.0 and 3-Matic Research 13.0, and subsequently analyzed in ANSYS Workbench 2024 R1. The model included explicit cortical, trabecular, and ligamentous volumes, each assigned linear-elastic, isotropic material properties based on biomechanical literature data. Boundary conditions simulated the mid-stance phase of race walking, applying a distributed plantar pressure of 0.25 MPa over the metatarsal and phalangeal regions. Numerical simulations yielded maximum total displacements of 0.00018 mm, maximum von Mises stresses of 0.171 MPa, and maximum strains of 2.5 × 10⁻⁵, all remaining well within the elastic range of bone tissue. The results confirm the model’s numerical stability, geometric fidelity, and capacity to represent physiologically realistic loading responses. The developed framework demonstrates the potential of high-resolution, image-based finite element modelling for investigating stress–strain patterns of the foot during athletic gait, and establishes a reproducible reference for future analyses involving pathological gait, orthotic optimisation, and musculoskeletal load assessment in sports biomechanics. Full article

Background: Only a limited number of studies have examined the effects of short-term, strength–speed-oriented velocity-based training (VBT) on lower-body power in female junior volleyball players and elite female artistic gymnasts. The present study aimed to investigate the impact of a four-week VBT intervention on jump performance and force–velocity characteristics in these athletes. Methods: Seven junior female volleyball players (age: 17.4 ± 0.9 years; height: 179.4 ± 6.5 cm; weight: 74.01 ± 3.5 kg) (top-league team members), and seven elite female artistic gymnasts (age: 17.6 ± 2.9 years; height: 159.6 ± 7.2 cm; weight: 59.3 ± 6.3 kg) (National Team members) completed two weekly training sessions for four weeks, each consisting of four sets of six repetitions of parallel back squats (PBSs) and hip thrusts (HTs). Training loads were regulated using barbell velocity targets (PBSs: 0.46–0.72 m/s; HTs: 0.36–0.60 m/s). Pre- and post-intervention assessments included loaded (15–60% body mass) and unloaded squat jumps (SJs) and countermovement jumps (CMJs) to determine peak power output, jump height, and force–velocity profiles. Results: Volleyball players showed significant improvements in peak power predominantly during loaded SJs (SJ45%: +5.5%, p < 0.01; SJ60%: +5.7%, p < 0.05), whereas gymnasts exhibited greater gains in loaded CMJs (CMJ60%: +7.7%, p < 0.01). In contrast, unloaded SJ and CMJ performances remained largely unchanged for all athletes. Both groups demonstrated a significantly steeper post-intervention force–velocity profile (p < 0.001), indicating an enhanced capacity to produce force at lower movement velocities under external loading. Conclusions: Strength–speed-oriented VBT was effective in improving power production under loaded conditions but had limited transfer to unloaded jump performance. These findings highlight the necessity of subsequent training blocks emphasizing high-velocity, sport-specific movements to optimize explosive performance. Future studies should further investigate low-velocity-loss training protocols as a potential means of enhancing unloaded jump outcomes. Full article

Skeletal muscle, the largest organ within the animal body, consists of multiple muscle fiber types. The distribution of these fiber types significantly impacts both athletic performance and the quality of meat. Growing evidence has demonstrated that transfer RNA (tRNA)-derived small RNAs (tsRNAs) are not merely byproducts of tRNA metabolism but also participate in multiple cellular metabolic processes. However, the role of tsRNAs in skeletal muscle fiber type transition remains elusive. In this study, a total of 403 differentially expressed tsRNAs were identified through small RNA sequencing in psoas major muscle (PM) and latissimus dorsi muscle (LD), among which 220 tsRNAs including tRF-Lys-TTT-012 were upregulated in psoas major muscle. Functional studies in C2C12 and PK15 cells demonstrated that it inhibited the proliferative capacity of C2C12 cells while promoting myogenic differentiation, increased the proportion of slow muscle fibers after differentiation, and drove muscle fiber type transition toward slow fibers. Additionally, tRF-Lys-TTT-012 enhanced mitochondrial number and function, potentially linking to the promotion of slow fiber characteristics. Collectively, tRF-Lys-TTT-012 may serve as a promising marker for slow muscle fibers and uncover a novel potential target for skeletal muscle fiber type transition toward the slow fiber phenotype. Full article

Applied muscular strain and hamstring strain capacity have a joint interaction on hamstring strain injury (HSI) with modifiable risk factors frequently assessed. However, to date there is limited observations on the interaction between these factors. The purpose of the present study was to observe if spatiotemporal characteristics, running kinematics and muscle activation were related to modifiable risk factors of HSI. Twenty-two competitive team sport athletes (24.7 ± 4.3 years, 1.82 ± 0.07 m, 84.9 ± 8.5 kg) participated whereby the Bicep femoris long head (BF_LH) fascicle length assessed via ultrasound and isokinetic eccentric hamstring strength was assessed. With running assessment performed at 18 km/h, capturing running kinematics and muscle activation. Multiple linear regressions were used to examine the relationship of running kinematics and muscle activation on the modifiable risk factors of HSI on. The overall model (F_2,19) was statistically significant for both relative eccentric hamstring strength (F = 23.58, p < 0.001) and BF_LH fascicle length (F = 18.87, p < 0.001) highlighting spatiotemporal characteristics, running kinematics and hamstring activation were found to be significantly related to the modifiable risk factors. There is a complex interrelationship between running mechanics and hamstring muscle properties, with the potential of either cause or consequence association. Full article