Background: This study investigated quadriceps femoris muscle activity by comparing concentric and eccentric contractions with self-selective squat speed. Objectives: Study participants agreed in advance and included 30 male college students in their 20s without musculoskeletal system disease. Design: A randomized controlled trial. Methods: Participants who participated in this study agreed in advance and recruited 30 male college students in their 20s who had no disease with musculoskeletal system to conduct this study. When squatting at a self-selected speed, the subjects were evaluated using one-way ANOVA to compare concentric and eccentric contraction muscle activity. Results: There were significant differences between the rectus femoris, vastus medialis, and vastus lateralis regarding concentric contractions.contractions. There was a significant difference in vastus medialis but no significant difference between rectus femoris and vastus lateralis for eccentric contractions. Conclusion: During concentric contraction, all muscles and eccentric contractions indicated significant improvement in the vastus medialis. Therefore, to minimize knee joint injury and maximize efficient muscle activity, self-selected slow and moderate speeds based on self-selection speed when performing the sit-down motion during a squat and moderate speed with fast motions when performing the standing motion should be considered as high muscle activities.

Background: Elastic and non-elastic taping are widely used in clinical practice, but there are various methods of attachment. Objectives: To investigate the effect of the type and intensity of taping on the muscle strength and muscle endurance of healthy adults. Design: Experimental research. Methods: 38 healthy adults participated in this experiment. Before applying the taping to each participant, the muscle strength and endurance of the quadriceps femoris were measured. After applying three different taping intervention methods, muscle strength and muscle endurance changes were measured. Muscle strength and endurance were measured through CSMI. Repeated measures ANOVA was used for statistics on participant measurements. Results: All intervention methods influenced the muscle strength improvement of the quadriceps femoris. Elastic tape with 50% elasticity had a greater impact on muscle strength than 33% elastic tape and non-elastic tape, and secondly, elastic tape with 33% elasticity was effective, and non-elastic tape had the least impact. Muscle endurance improvement was affected by the order of 50% elasticity taping, 33% elasticity taping, and non-elastic taping. Conclusion: All three taping intervention methods showed significant effects on improving muscle strength and muscle endurance of the wide-legged quadruple muscles, but the best effect was to apply 50% elastic taping.