Taekwondo (TKD) is a popular sport among adolescents, but the potential benefits of TKD training to young individuals are not well understood. The objectives of this cross-sectional exploratory study were to compare flexibility, muscular endurance, body composition, and simple reaction time between TKD-trained adolescents and controls. Twenty TKD-trained adolescents aged between 10 and 14 and 20 age-matched healthy controls were asked to perform five physical fitness tests: a sit-and-reach test, leg split test, skinfold measurement, one-minute curl-up test, and ruler-drop reaction time test. The results revealed no significance differences between the two groups in sit-and-reach distance (p = 0.690), leg split angle (p = 0.789), percentage of body fat (p = 0.342), or number of repetitions in the one-minute curl-up test (p = 0.250). However, the TKD group had significantly faster reaction times in the rulerdrop test than the control group (p = 0.005). The results thus suggest that although TKD training may improve reaction times in adolescents, it may have little effect on flexibility, muscular endurance, and body composition (percentage of fat). TKD may be a suitable exercise for improving simple reaction time, but it may not be suitable for improving general physical fitness in adolescents.
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