Resistance training is considered to be an efficient treatment for age-related sarcopenia and can improve muscle strength and quality in patients. However, there are currently no recommendations on resistance training parameters to improve muscle strength and quality in elderly patients with sarcopenia. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) and included 13 eligible RCTs. Resistance training significantly improved grip strength, gait speed, and skeletal muscle index in patients with age-related sarcopenia, and kettlebell was found to be the most effective modality. However, it is noteworthy that the elastic band is also a recommended form of resistance training considering that the kettlebell intervention was tested in only one study, while the elastic band was confirmed by multiple studies. Elastic band training (Hedges’s g = 0.629, 95%CI = 0.090–1.168, p < 0.05) (40–60 min per session, more than three times per week for at least 12 weeks) was the most efficient training method. Thus, resistance training can significantly improve muscle strength and muscle quality in elderly patients with sarcopenia. In addition, moderate-intensity resistance training using elastic bands may be the best training prescription for elderly patients with sarcopenia.

The aim of this study was to investigate the effect of different training modalities on improving the inflammatory response in adolescents with obesity. For the study methodology, the databases such as China National Knowledge Infrastructure (CNKI), Wanfang Data, Pubmed, Web of Science, and EBSCO were selected for searching. The methodological quality of the included studies was assessed using the Cochrane Risk of Bias (ROB) tool, and statistical analysis was performed by applying RevMan 5.4.1 analysis software. A total of 14 studies with 682 subjects were included. The results of this meta-analysis showed that aerobic training (AT) and aerobic plus resistance training (AT + RT) reduced the levels of IL-6 and CRP in adolescents with obesity. Among them, AT + RT was more effective than other training modalities in reducing IL-6 and CRP in adolescents with obesity. Different training modalities have no effect on the TNF-α level in adolescents with obesity. However, regarding the increase in IL-6, CRP, and TNF-α in adolescents with obesity, resistance training (RT) did not lead to significant differences. In conclusion, long-term regular AT, AT + RT, and HIIT are all helpful in improving the inflammatory state of adolescents with obesity, with AT + RT being the best training modality to combat inflammation in adolescents with obesity.

Torsional stiffness of athletic footwear plays a crucial role in preventing injury and improving sports performance. Yet, there is a lack of research focused on the biomechanical effect of torsional stiffness in badminton shoes. This study aimed to comprehensively investigate the influence of three different levels of torsional stiffness in badminton shoes on biomechanical characteristics, sports performance, and injury risk in badminton players. Fifteen male players, aged 22.8 ± 1.96 years, participated in the study, performing badminton-specific tasks, including forehand clear stroke [left foot (FCL) and right foot (FCR)], 45-degree sidestep cutting (45C), and consecutive vertical jumps (CVJ). The tasks were conducted wearing badminton shoes of torsional stiffness measured with Shore D hardness 50, 60, and 70 (referred to as 50D, 60D, and 70D, respectively). The primary biomechanical parameters included ankle, knee, and MTP joint kinematics, ankle and knee joint moments, peak ground reaction forces, joint range of motion (ROM), and stance time. A one-way repeated measures ANOVA was employed for normally distributed data and Friedman tests for non-normally distributed data. The 70D shoe exhibited the highest ankle dorsiflexion and lowest ankle inversion peak angles during 45C task. The 60D shoe showed significantly lower knee abduction angle and coronal motions compared to the 50D and 70D shoes. Increased torsional stiffness reduced stance time in the FCR task. No significant differences were observed in anterior-posterior and medial-lateral ground reaction forces (GRF). However, the 70D shoe demonstrated higher vertical GRF than the 50D shoe while performing the FCR task, particularly during 70% - 75% of stance. Findings from this study revealed the significant role of torsional stiffness in reducing injury risk and optimizing performance during badminton tasks, indicating that shoes with an intermediate level of stiffness (60D) could provide a beneficial balance between flexibility and stability. These findings may provide practical references in guiding future badminton shoe research and development. Further research is necessary to explore the long-term effects of altering stiffness, considering factors such as athletic levels and foot morphology, to understand of the influence of torsional stiffness on motion biomechanics and injury prevalence in badminton-specific tasks.

This systematic review, registered in PROSPERO (CRD42025101243), aimed to evaluate how specific badminton shoe design features influence lower-limb biomechanics, injury risk, and sport-specific performance. A comprehensive search in six databases yielded 445 studies, from which 10 met inclusion criteria after duplicate removal and eligibility screening. The reviewed studies focused on modifications involving forefoot bending stiffness, torsional stiffness, lateral-wedge hardness, insole and midsole hardness, sole structure, and heel curvature. The most consistent biomechanical benefits were associated with moderate levels of forefoot and torsional stiffness (e.g., 60D) and rounded heel designs. Increased forefoot bending stiffness was associated with reduced foot torsion and knee loading during forward lunges. Torsional stiffness around 60D provided favorable ankle support and reduced knee abduction, suggesting potential protection against ligament strain. Rounded heels reduced vertical impact forces and promoted smoother knee–ankle coordination, especially in experienced athletes. Lateral-wedge designs improved movement efficiency by reducing contact time and enhancing joint stiffness. Harder midsoles, however, resulted in increased impact forces upon landing. Excessive stiffness in any component may restrict joint mobility and responsiveness. Studies included 127 male-dominated (aged 18–28) competitive athletes, assessing kinematics, impact forces, and coordination during sport-specific tasks. The reviewed studies predominantly involved male participants, with little attention to sex-specific biomechanical differences such as joint alignment and foot structure. Differences in testing methods and movement tasks further limited direct comparisons. Future research should explore real-game biomechanics, include diverse athlete populations, and investigate long-term adaptations. These efforts will contribute to the development of performance-enhancing, injury-reducing badminton shoes tailored to the unique demands of the sport.

Background: Body mass index (BMI) is routinely used in university health surveillance, but its sex- and grade-specific association with multidimensional physical fitness, including nonlinear patterns, remains unclear. Methods: Data from 16,292 university students (8,505 females; 7,787 males; aged 17–23 years) who completed the national standardized fitness assessment were analyzed in this cross-sectional study. Vital capacity, 50-m sprint, standing long jump, sit-and-reach, 800/1,000-m run, and muscular endurance were standardized within sex to derive a Physical Fitness Index (PFI), with time-based tests reverse-scored. Two-way analyses of variance examined associations of sex, academic grade, and BMI category with PFI. Sex- and grade-specific quadratic models were used to characterize BMI–PFI curves and estimate the model-derived BMI value associated with peak predicted PFI. Pearson correlations assessed associations between PFI and individual fitness components. Results: Academic grade was associated with PFI, whereas no overall sex effect was observed (sex: F (1, 16,284) = 1.51, p = 0.219, partial η ² = 0.000093; grade: F (3, 16,284) = 74.54, p < 0.001, partial η ² = 0.0136). The sex × grade interaction was statistically significant but small ( F (3, 16,284) = 20.44, p < 0.001, partial η ² = 0.00375). Within both sexes, normal-weight students showed the highest PFI; underweight students had higher PFI than overweight and obese peers, while PFI was lower in the overweight and obese groups. The BMI–PFI association was stronger in males (partial η ² = 0.1061) than in females (partial η ² = 0.0287). All quadratic models showed a concave BMI–PFI pattern, with lower predicted PFI at higher BMI values and model-derived peak estimates varying across sex–grade subgroups. These estimates should not be interpreted as physiological optima or recommended BMI targets. Correlations indicated that PFI integrated cardiorespiratory fitness, lower-limb power, flexibility, muscular endurance, and running performance. Conclusion: BMI was associated with multidimensional physical fitness in this large cohort of university students, with lower PFI observed at both low and high BMI values. BMI showed a stronger association with PFI than academic grade, particularly in males. These findings support BMI-informed and sex-sensitive fitness monitoring, but should be interpreted as cross-sectional associations because body-composition and behavioral measures were unavailable.