The aim of the present study was to investigate the acute effect of caffeine supplementation on performance in official soccer matches. In double-blind, randomized crossover design, 13 professional soccer players performed two complete matches, with Caffeine (CAF) (6 mg/kg) and placebo (PLA) supplementation. Two-way repeated measures ANOVA showed that there was no effect of supplementation on the total distance covered (p = 0.536; ŋp² =0.033) or the total distance covered at different speeds (p = 0.453; ŋp² = 0.048), acceleration or deceleration (p = 0.387; ŋp² = 0.063) number of sprints (p = 0.521; µ² = 0.035) Heart Rate mean (p = 0.484; ŋp² = 0.042) Heart Rate maximum (p = 0.110; ŋp² = 0.199), Rate Perceived Effort (p = 0.151) or efficiency index (p = 0.480). Therefore, acute caffeine supplementation not effective to increase the performance of soccer players in official matches.

The present study aimed to develop a mathematical model to estimate the performance of an indoor rowing event of 6000m through an 500 m all out test in junior athletes. We selected141 subjects from the Brazilian rowing confederation database (15.9 ± 1.0 years), subsequently randomised the sample to the development (~70%) and cross-validation (~30%) groups of the mathematical model. Performance data for 500m and 6000m were collected (there was a 48h washout between one test and anoth-er).Subsequently, the mathematical model: Time(min) 6000m = { [( Time(s) 500-m * 6) * 2] / 60} + 1.3, was developed by arithmetic modeling using machine learning and Regression analysis, being tested by intraclass correlation coefficient (ICC), Concordance correlation coefficient (CCC), Validity (Cb ), preci-sion (ρ) and bland-Altman plotting. The prediction of the result of 6000m through the mathematical model utilizando apenas o desempenho de 500m “all-out” test showed a significant reliability in de-velopment group (r2 = 0.730, ICC = 0.753; CCC = 0.895, Cb = 0.879, ρ: 0.957, pure error: 0.2 secounds (1.0% estimative error)); and in cross-validation group (r2 = 0.710, ICC = 0.747; CCC = 0.888, Cb = 0.875, ρ: 0.903, pure error: 0.3 secounds (1.4% estimative error)). When comparing the estimated re-sults of the 6000m performance by the mathematical model with the real performance of 6000m per-formed in indoor rowing, no statistical differences were observed. In addition, the mathematical model did not present a significant proportion bias in relation to the 6000 m performance in both groups. The mathematical model for predicting 6000m performance through a 500m fast test was significant for national level junior rowing athletes.

Objectives: This study examined the effects of kinesio tape (KT) on the rectus femoris muscle under pre- and post-fatigue conditions, with trained and novice participants. Methods: Nineteen male volunteers took part, and fatigue was assessed using the Borg CR10 Scale. Kinematic and kinetic data were collected using Vicon MX13+ infrared cameras (250 Hz) and Kistler force platforms (1500 Hz), respectively. Visual 3D software analyzed the data, focusing on parameters like angular displacement, ground reaction forces (GRF), impulse, and joint moments during a stop-jump task. A two-way mixed-design ANOVA was used to assess group, fatigue, and KT effects. Results: The results showed significant differences in knee flexion range of motion (ROM), hip flexion moment, vertical impulse, and peak vertical GRF between pre- and post-fatigue conditions (all p < 0.05). The trained group exhibited less knee valgus ROM, higher hip flexion velocity at initial contact, and prolonged time to peak proximal tibia anterior shear force. Conclusions: KT application was found to reduce lower limb loading, improve force acceptance and joint stability, and alleviate fatigue-induced disparities. These findings highlight the potential of KT in enhancing lower limb strength and performance, particularly under fatigue.

This research delved into exploring the impact of ladder training on improving the athletic performance of adolescent students, particularly focusing on boosting explosive power and speed. The study involved thirty boys aged 15-17, selected randomly from an Indian school in Doha, Qatar. The variables measured were Explosive Power (EP) and speed (S). EP was assessed using the Standing Broad Jump (SBJ), while Speed (S) was gauged through the 50-yard dash. Divided into two groups - the Experimental Group (EG) and the Control Group (CG), each consisting of fifteen students - the EG underwent dedicated ladder training for 12 weeks while the CG continued their routine. Analysis of pre-test and post-test results indicated significant enhancements in EP and speed within the EG, with notable shifts from 2.15±.27 to 2.40±.24and 7.52±.54to 6.97±.66, respectively, exhibiting significant 't' values (EP: -2.39; speed: 2.23) at P˂.05. Conversely, the CG showed minimal changes in EP (pre: 2.22±.22; post: 2.2±.21) and speed (pre: 7.51±.43; post: 7.58±.72), with 't' values of 0.295 and 0.842, respectively, failing to reach significance at P˂.05. These outcomes highlight the efficacy of ladder training in improving explosive power and speed among adolescent students, suggesting its potential as a safe and advantageous component in athletic training programs.

This study assessed the relationship between body posture displacements and cardiopulmonary function test (CPET) and skill related physical fitness tests. One hundred male (60%) and female collegiate athletes (22.2 ± 4yrs) with a normal body mass index (BMI up to 24.9) were assessed via the PostureScreen Mobile app to quantify postural displacements as head, thorax and pelvis rotations and translations. CPET and physical performance tests including the agility T-test, the vertical jump test, the stork static balance test (SSBT) and the dynamic Y-balance test (YBT) were performed. Spearman correlation (r) and p-values are reported. Postural parameters were found to have moderate-to-high associations with CPET and the agility test, moderate correlations with the vertical jump test and the SSBT (head and pelvic postures only), and weak correlations with the YBT. As postural parameters were more asymmetric, both CPET and performance skills scores were worse. For examples: 1) a medium positive correlation was found between cranio-vertebral angle (CVA) and vertical jump test (r = 0.54; p-value < 0.001) and SSBT (r = 0.57; p-value < 0.001), while a strong negative correlation was found between CVA and agility test (r = -0.86; p-value < 0.001). 2) A strong positive correlation was found between CVA and oxygen uptake efficiency slope, load watts VO2 at VT, VO2 / kg, load watts at respiratory compensation point (RCP), (r = 0.65 and r = 0.71; p < 0.001). Conversely, a significant negative correlation was found between CVA and VE / VO2 at VT (r = -0.61; p < 0.001). Postural rotations and translations of the head, thorax and pelvis were statistically correlated with physical performance skills and CPET in young collegiate athletes. There were moderate-to-high associations with cardiopulmonary functions and agility tests, moderate correlations with the vertical jump test, and weak correlations with the YBT. Postural alignment may be important for optimal physical performance and optimal cardiopulmonary function. Further research is necessary to elucidate reasons for these correlations as found in our sample of young and healthy athletes.

Sex dimorphism starts during early embryogenesis and is further manifested in response to hormones during puberty. As this leads to physical divergence that is measurably different between sexes, males enjoy physical performance advantages over females within competitive sport. While this advantage is the underlying basis of the segregation into male and female sporting categories, these sex-based categories do not account for transgender persons who experience incongruence between their biological sex and their experienced gender identity. Accordingly, the International Olympic Committee determined criteria by which a transgender woman may be eligible to compete in the female category, requiring total serum testosterone levels to be suppressed below 10 nmol/L for at least 12 months prior to and during competition. Whether this regulation removes the male performance advantage has not been collectively scrutinized. Here, we aim to review how differences in biological characteristics between biological males and females affect sporting performance and assess whether evidence exists to support the assumption that testosterone suppression in transgender women removes the male performance advantage. In this review, we report that the performance gap between males and females amounts to 10-50% depending on sport. The performance gap is more pronounced in sporting activities relying on muscle mass and strength, particularly in the upper body. Longitudinal studies examining the effects of testosterone suppression on muscle mass and strength in transgender women consistently show very modest changes, where the loss of lean body mass, muscle area and strength typically amounts to approximately 5% after 1 year of treatment. Thus, current evidence shows that the biological advantage enjoyed by transgender women is only minimally reduced when testosterone is suppressed. Sports organizations may therefore be compelled to reassess current policies regarding participation of transgender women in the female category of sport.

This study analyzed the relationship between anthropometric measures, cardiorespiratory capacity, strength, power and local muscle endurance with performance in the CrossFit® Open 2020. For this, 17 volunteers (6 women) (29.0 ± 7.2 years; 70.5 ± 9.8 kg) completed, on separate weeks, body composition (dual-energy x-ray absorptiometry), maximal oxygen consumption (2km row test), muscle strength (1RM back and front squat, isometric peak torque), and muscle power (1RM snatch and clean & jerk), and muscle endurance (Tibana test), which were compared with performance during the CrossFit® Open 2020. Multiple linear regression showed that for the CrossFit Open 2020.1 and 2020.2 workouts, the score in the Tibana test was the only variable that explained the outcomes (Beta = -0.78, p < 0.01 for 2020.1 workout and Beta = 0.82, p < 0.01 for 2020.2 workout). Performance in the CrossFit Open 2020.3 and 2020.4 workouts were explained through the relative strength (Beta = 0.58, p = 0.02 for 2020.3 workout and Beta = 0.50, p = 0.04 for 2020.4 workout). Lastly, Tibana test had the greatest influence on CrossFit Open 2020.5 workout (Beta = -0.75, p < 0.01). A local muscle endurance and muscle strength may be used to predict CrossFit® open workout performance.

Throughout this paper the impact of anxiety on adolescent athlete’s is highlighted through analyzing neurological and psychological aspects involved in sports performance. The neuroanatomy and neuropsychology of the human brain plays a major role in developing athlete’s that has only begun to be analyzed within recent years. Especially in young athletes, there are numerous factors that affect performance on the field that originate from the environment and training the adolescent athlete is involved in. Sports performance is viewed as a major physical factor such as training and lifting weights, however the psychological aspect of sports performance often goes unnoticed. Athletes can begin to develop mental fatigue and anxiety which inevitably can decrease their ability to perform. The athlete’s internal suffering begins to go unnoticed, as the only tangible factor is watching their performance decrease. This causes the athlete to push themselves further in training resulting in greater mental fatigue. This paper emphasizes the numerous factors neurologically that play a role in athletic performance which should be focused on in adolescent athletes as they navigate the challenges and competition that are apparent within athletics. It is critical to understand the processes and hormonal changes the body undergoes with training and playing a sport, this information can change the way adolescent sports are approached and advanced.

Knowledge of body composition is essential for athletes for their sport performance. It has yet to be determined whether differences in body composition are present between international and non-international players playing in the same elite professional club competition. Similarly, it is not yet clear whether differences in body composition according to ethnic origin exist in the elite professional game, where relative homogeneity is to be expected among soccer players. There is no single anthropometric profile that guarantees sporting success, as the somatotype of football players differs according to their individual characteristics. The aim of this study was to assess the description and comparison of the body composition profile of latin american professional football players playing in european leagues. The sample was composed of 238 subjects football players from European professional football leagues. Differences were found in all variables measured. The present study shows that in Latin American professional football players playing in Europe, there are significant differences in different body composition variables such as weight, height, WC, skinfold and fat values. This means that the treatment of these data and the possible classifications of sporting performance carried out in football clubs should be different to other European or African-American football players.

Orofacial injuries are common occurrences during contact sports activities; however, there is an absence of data regarding the performance of hybrid occlusal splint mouthguards, especially during compressive loading. To evaluate the total deformation and stress concentration, a skull model was selected and duplicated to receive two different designs of mouthguard devices: one model received a conventional custom-made mouthguard (MG) with 4-mm thickness and the other received a novel hybrid occlusal splint-mouthguard (HMG) with the same thickness. Both models were subdivided into finite elements. The frictionless contacts were used, and a nonlinear analysis was performed simulating the compressive loading in occlusion. The results were presented in von-Mises stress maps (MPa) and Total Deformation (mm). A higher stress concentration in teeth was observed for the model with the conventional MG, while the HMG design displayed a promising mechanical response with lower stress magnitude. The HMG de-sign displayed a higher magnitude of stress on its occlusal portion than the MG design. The hybrid mouthguard (HMG) reduced (1) jaw displacement during chewing and (2) the generated stresses in maxil-lary and mandibular teeth.

The purpose of this study was to investigate the relationships among student athlete’s identity and mental health during the COVID-19 pandemic. In addition, this study aimed to clarify the relationship between perceived social support from teammates and mental health in student-athletes. Two studies were conducted to investigate to clarify the mental health states of student-athletes in Japan during the COVID-19 pandemic. In Study 1 conducted in April 2020, the participants were 402 male student-athletes, and examined the relationships among student-athlete’s identity and mental health. The results of correlational analyses indicated that there were significant negative correlations between degree of student-athlete’s identity and depression and sports helplessness. In Study 2 conducted in March 2021, the participants were 136 male student-athletes, and examined the relationship between perceived social support from teammates, student-athlete’s identity and mental health. The results indicated that there was significant correlation among social support, student athlete’s identity and mental health. These results suggested that mental health may be improved if student-athletes are strongly aware of their social identity, which is their social role, when unforeseen events such as the COVID-19 pandemic occur. In addition, social support provided by significant others such as teammates may contribute to the improvement of mental health.

Background/Objectives: This study aimed to evaluate the effects of an 8-week combined plyometric and resistance training program on the physical fitness of adolescent girls aged 12 to 15 years. The objective was to determine whether combined training (CT) would yield greater improvements in performance measures compared to resistance training (RT) alone. Methods: Forty-seven adolescent girls were randomly assigned to either the CT group or the RT group. Performance measures such as the 20-meter sprint, squat jump, vertical jump, handgrip strength, and flexibility (sit and reach test) were assessed before and after the 8-week interven-tion. Changes in these measures were analyzed to compare the effects of the two training ap-proaches. Results: The CT group showed a significant reduction in sprint time (-6.5%) compared to the RT group (-4.1%), although the difference was not statistically significant. Squat jump height im-proved significantly by 5.6% in the CT group compared to 1.1% in the RT group (p < 0.05). Simi-larly, vertical jump height increased by 6.7% in the CT group and by 2.4% in the RT group (p < 0.05). Handgrip strength improved by 7.5% in the CT group and 4.6% in the RT group, with no significant differences between the groups. Flexibility showed slight, non-significant improve-ments in both groups. Conclusions: The findings suggest that combined plyometric and resistance training is more ef-fective in enhancing explosive power, specifically squat and vertical jump performance, in ado-lescent girls compared to resistance training alone. These results highlight the potential of com-bined training programs for improving overall physical performance in this population.

Post-exercise recovery is fundamental to optimizing athletic performance, focusing on muscle repair, glycogen replenishment, rehydration, and reducing exercise-induced inflammation. This review examines the evolving landscape of recovery nutrition, highlighting the transition from conventional supplements—such as protein, carbohydrates, creatine, and branched-chain amino acids (BCAAs)—to functional foods rich in bioactive compounds. Emerging evidence supports the efficacy of functional foods like tart cherry juice, turmeric, and omega-3 fatty acids in mitigating oxidative stress and inflammation, thus accelerating recovery. Additionally, probiotics and prebiotic-rich foods are gaining recognition for enhancing gut health, promoting nutrient absorption, and strengthening immune function, which are crucial in recovery processes. The concept of personalized nutrition, guided by genetic and metabolic profiling, is explored as a promising approach to tailor recovery strategies to individual physiological needs. Continued research into the long-term effects of supplements, the role of functional foods, and nutrient interactions is essential for developing more comprehensive and individualized recovery protocols. Integrating functional foods with personalized nutrition offers a holistic strategy to enhance recovery, optimize performance, and promote long-term health in athletes.

Cervical injuries from athletic activities are rare; they can have severe consequences if not diagnosed and managed promptly. The choice of diagnostic imaging modality is pivotal in ensuring timely and accurate diagnosis. We detail the case of a 19-year-old female athlete who sustained a C2 Durel Type II Subclass C fracture during a short-track speed skating championship. Initial evaluation using X-ray imaging at the athletic center medical facility did not detect the injury, allowing her to continue competing. Persistent pain led to further evaluation at our institution, where MRI and CT scans confirmed the fracture. Approximately 45 days post-injury, the patient underwent a successful surgical intervention utilizing O-arm CBCT navigation for C1-C2 dorsal fusion. Post-surgery, she embarked on a comprehensive rehabilitation program and fully recovered within 12 weeks. This case underscores the limitations of relying solely on X-ray imaging for diagnosing cervical fractures post-trauma. Our findings advocate prioritizing CT scans as a primary diagnostic tool in such scenarios, emphasizing the need for a robust diagnostic approach to ensure athlete safety and well.

Interviews from strength and conditioning coaches across all levels of athletic competition identified their two biggest concerns with the current state of wearable technology: (a) the lack of solutions that accurately capture data "from the ground up" and (b) the lack of trust due to inconsistent measurements. The purpose of this research is to investigate the use of liquid metal sensors, specifically Liquid Wire sensors, as a potential solution for accurately capturing ankle complex movements such as plantar flexion, dorsiflexion, inversion, and eversion. Sensor stretch linearity was validated using a Micro-Ohm Meter and a Wheatstone bridge circuit. Sensors made from different substrates were also tested and discovered to be linear at multiple temperatures. An ankle complex model and computing unit for measuring resistance values were developed to determine sensor output based on simulated plantar flexion movement. The sensors were found to have a significant relationship between the positional change and the resistance values for plantar flexion movement. The results of the study ultimately confirm the researchers' hypothesis that liquid metal sensors, and Liquid Wire sensors specifically, can serve as a mitigating substitute for inertial measurement unit (IMU) based solutions that attempt to capture specific joint angles and movements.