Background: Normative foot kinematic and kinetic data with different walking speeds will benefit rehabilitation programs and improving gait performance. The purpose of this study was to analyze foot kinematics and kinetics differences between slow walking (SW), normal walking (NW) and fast walking (FW) of healthy subjects. Methods: A total of 10 healthy male subjects participated in this study; they were asked to carry out walks at a self-selected speed. After measuring and averaging the results of NW, the subjects were asked to perform a 25% slower and 25% faster walk, respectively. Temporal-spatial parameters, kinematics of the tibia (TB), hindfoot (HF), forefoot (FF) and hallux (HX), and ground reaction forces (GRFs) were recorded while the subjects walked at averaged speeds of 1.01 m/s (SW), 1.34 m/s (NW), and 1.68 m/s (FW). Results: Hindfoot relative to tibia (HF/TB) and forefoot relative to hindfoot (FF/HF) dorsiflexion (DF) increased in FW, while hallux relative to forefoot (HX/FF) DF decreased. Increased peak eversion (EV) and peak external rotation (ER) in HF/TB were observed in FW with decreased peak supination (SP) in FF/HF. GRFs were increased significantly with walking speed. The peak values of the knee and ankle moments in the sagittal and frontal planes significantly increased during FW compared with SW and NW. Discussion: Limited HF/TB and FF/HF motion of SW was likely compensated for increased HX/FF DF. Although small angle variation in HF/TB EV and FF/HF SP during FW may have profound effects for foot kinetics. Higher HF/TB ER contributed to the FF push-off the ground while the center of mass (COM) progresses forward in FW, therefore accompanied by higher FF/HF abduction in FW. Increased peak vertical GRF in FW may affected by decreased stance duration time, the biomechanical mechanism maybe the change in vertical COM height and increase leg stiffness. Walking speed changes accompanied with modulated sagittal plane ankle moments to alter the braking GRF during loading response. The findings of foot kinematics, GRFs, and lower limb joint moments among healthy males may set a reference to distinguish abnormal and pathological gait patterns.

The aim of this study is to review the valuable lower limb biomechanical contribution to table tennis topspin forehand. Databases included Scopus, PubMed, and Web of science. In this case, 19 articles were selected for the systematic review. The mechanics of the plantar, lower limb joints kinematics and kinetics, muscle activity, and racket-joint relationship are described through gender, performance level, and footwork. The study found that the hip movement characteristics and the hip muscle group activity following a proximal-to-distal sequence strategy significantly contributed to the maximum acceleration of the racket. Optimizing the motion strategy of the ankle and plantar as well as the ankle muscle group activity is beneficial for the transmission of energy in the kinetic chain. Muscle groups around the ankle and subtalar joints are heavily activated during landing to maintain foot stability during the landing phase. Lower limb muscle development plays an important role in movement control and stability as well as sports injury prevention in table tennis footwork during the performance of the topspin forehand. Furthermore, physical development levels and anatomical differences (such as hip and lower trunk muscle strength differences), maybe the main reasons for gender differences observed during the topspin forehand. Systematically summarizing this valuable information can contribute to athletes’ and coaches’ knowledge to enhance topspin forehand performance and training regimes. We suggest that future research could consider the joint contact forces, ball movement, and ball-racket impact during a performance of topspin forehand.

A coronavirus pandemic has recently become one of the greatest threats the world is facing. Older adults are under a high risk of infection because of weaker immune systems. Therefore, the purpose of this review is to summarize the recent scientific evidence that outlines the effects of exercise on influenza or pneumonia in older adults. An electronic literature search was conducted using the WEB OF SCIENCE, SCIENCEDIRECT and GOOGLE SCHOLAR databases using the following keywords, “Exercise,” “Older adult,” “Influenza,” and “Pneumonia.” Any randomized control trials, cross-sectional and observational studies that related to this topic were all included. Twenty studies met the eligibility criteria for this review. Thirteen randomized control trials investigated the effects of exercise on the immune responses to influenza or pneumonia vaccination: seven trials employed moderate aerobic exercise, three employed resistance exercise, and the remaining three used Asian martial arts or special home-based exercises. Five cross-sectional and two observational studies examined the associations between exercise/physical condition and influenza/pneumonia. Most of the current studies suggested that prolonged moderate aerobic exercise may help to reduce the risk of influenza-related infection and improve the immune responses to influenza or pneumonia vaccination in older adults. In addition, training in traditional Asian martial arts was also found to be beneficial. Future research should focus on the different effects of moderate and vigorous exercise on influenza-related diseases.

The purpose of this study was to determine the differences in technical characteristics between top-elite and sub-elite male weightlifters performing the snatch style in the 69-kg category. The obtained results can provide valuable information for lower level lifters and coaches to achieve better competition performance by altering their training methods accordingly. Six top-elite and six sub-elite weightlifters participated in this study. The heaviest successful snatch lift from the three attempts of each subject was analyzed. The video data were recorded under competition conditions at China National Weightlifting Championship and China Olympic Trial, which were analyzed by SIMI°Motion7.50 3D analysis system. The results showed that the maximum vertical- and relative vertical height (normalized by athletes' height) of the barbell, the maximal vertical linear velocity and acceleration of the barbell were significantly greater in top-elite lifters (p < 0.05). In addition, the flexion angles of the knee joint were significantly greater in top-elite lifters during the first phase and the third phase of the snatch lift. Sub-elite lifters showed less flexion and significantly slower angular velocity in knee joint than top-elite lifters during the second phase of the snatch lift (p < 0.05). The findings of the present study demonstrated the differences in technical characteristics between the two levels. According to these findings, coaches of sub-elite lifters should focus on exercises suitable to the strength characteristics of the first and the third phase of the snatch lift. In addition, the flexor muscles of knee joint among the sub-elite lifters should be strengthened and the ability of generating and utilizing elastic energy during the second phase of the snatch lift should be improved.

This study presented a systematic review of recent advancements in the application of finite element (FE) methods to running and running shoe biomechanics. It focused on outlining the general approach to build foot-running shoe FE models, exploring their current applications and challenges, and providing directions for future research. The review also aimed to highlight the gap between theoretical mechanical responses in simulations and real-world manifestations of running-related musculoskeletal injuries (RRMI). A comprehensive search of electronic databases, including Web of Science, PubMed, and Scopus, identified 12 eligible articles for inclusion in this review. Current studies have examined the effects of various running shoe design features and conditions on the mechanical response of internal foot tissues using foot-running shoe FE models. These models have gradually evolved from simplified local representations to more realistic and comprehensive models, with the incorporation of experimental data enhancing simulation accuracy. However, to further improve simulation outcomes, key advancements are proposed to reduce development time and enhance model robustness. These include high-fidelity 3D model development, personalized shape transformation, AI-driven automated reconstruction, comprehensive dynamic running simulations, and improved validation methods. More importantly, future research needs to bridge the gap between FE simulations and RRMI risk by addressing the complexities of bone fracture criteria and conducting localized assessments of bone properties. Overall, this review provided valuable insights for biomedical engineers, medical professionals, and researchers, facilitating more accurate investigations of foot-running shoe FE models. Ultimately, these advancements aim to improve footwear design and training programs to reduce the risk of RRMI.

Although various sports footwear demonstrated marked changes in running biomechanical variables, few studies have yielded definitive findings on the underlying mechanisms of shoe constructions affecting running-related performance and injuries. Therefore, this study focused on examining the effect of basic shoe constructions on running biomechanics and assessing the current state of sports shoe production in terms of injury and efficiency. Relevant literature was searched on five databases using Boolean logic operation and then screened by eligibility criteria. A total of 1260 related articles were retrieved in this review, and 41 articles that met the requirements were finally included, mainly covering the influence of midsole, longitudinal bending stiffness, heel-toe drop, shoe mass, heel flare, and heel stabilizer on running-related performance and injuries. The results of this review study were: (1) The functional positioning of running shoe design and the target groups tend to influence running performance and injury risk; (2) Thickness of 15–20 mm, hardness of Asker C50-C55 of the midsole, the design of the medial or lateral heel flares of 15°, the curved carbon plate, and the 3D printed heel cup may be beneficial to optimize performance and reduce running-related injuries; (3) The update of research and development concepts in sports biomechanics may further contribute to the development of running shoes; (4) Footwear design and optimization should also consider the influences of runners’ strike patterns.