In this study, we examined the relationship between physical function and muscle strain of hamstrings in junior high school soccer players. The subjects were 29 junior high school soccer players. The muscle strength of knee flexors and extensors relative to body weight and the hamstrings/quadriceps muscle strength ratio (H/Q ratio) were measured, and a tightness test, general joint looseness test and the New Physical Fitness Test of Japanese Ministry of Education and science were performed. We contacted the trainer to confirm occurrence of hamstrings strain, and we compared the above measurement and test results in subjects with and those without hamstring strain. Differences were analyzed by the unpaired t-test. There were significant differences between the two groups in muscle strength of knee extensors, H/Q ratio and tightness of hamstrings (p<0.05). The results suggest that increasing the H/Q ratio and stretching hamstrings are important for preventing hamstrings strain in junior high school soccer players.

Objective: To assess the relationships between phase angle and muscle mass, strength, and physical function in patients with heart failure. Methods: This study used a cross-sectional design. The analysis included 51 patients with heart failure. The Short Physical Performance Battery, one-leg standing time, handgrip strength, phase angle, and skeletal muscle index were measured. To identify explanatory variables of phase angle, hierarchical multiple regression analysis was performed. Results: Handgrip strength was found to be an explanatory variable of phase angle independent of age, sex, and body mass index. This model was able to explain 30.4% of the model variance for phase angle. Conclusion In patients with heart failure, improving muscle strength rather than muscle mass or physical function might be more important for improving phase angle. Handgrip strength is an important outcome for improving prognosis in patients with heart failure.

Objective: This study aimed to characterize the muscle strength and skeletal muscle mass of patients with heart failure by investigating hand-grip strength, five times sit-to-stand (5STS) results, and skeletal muscle mass index (SMI).Materials and Methods: Muscle strength was assessed based on hand-grip strength and 5STS, while skeletal muscle mass was assessed using a bioelectrical impedance analyzer. Hierarchical logistic regression analysis was performed to explore the association between patients with heart failure and healthy elderly individuals.Results: Hierarchical logistic regression analysis was performed to examine the muscle strength and skeletal muscle mass characteristics in patients with heart failure. Hand-grip strength and 5STS responses but not SMI outcomes differed significantly between the two groups. The results of the hierarchical logistic regression analysis revealed that the hand-grip strength and 5STS were significant predictors of heart failure. The odds ratios for hand-grip strength and 5STS were 1.44 and 0.53, respectively.Conclusion: Our results suggested that upper and lower limb muscle strengths (handgrip strength and 5STS) in elderly patients with heart failure worsened significantly without a decrease in skeletal muscle mass.