A Basic Study on the Optimum Time to Learn the Crouching Start, Overhand Throwing, and Walking on Stilts - Effectiveness of the Practice in Different Ages -

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We did three investigations to clarify when would be the best time for children to learn the crouching start in sprinting, over-hand throwing with a tennisball, and walking on stilts, from the view point of effctiveness of practice. The results suggested that the crouching start became effective not so much because of increased muscle strength as because of manner in which the muscle strength was used. That is, the muscle were activated in a new way for an effective crouching start. We had 132 boys from fifth grade in elementary school through junior high school practice the crouching start 20 minutes a day over a seven day period. the practice was most effective in the first and second year junior high school students. We had 278 children from first grade in elementary school through junior high school practice the over-hand throwing a tennisball for four weeks (4 days per week). The efof practice on throwing ability was greatest in boys at seven and eight years of age, and in girls at eight to ten years of age. this corresponded well with the age ranges at which throwing distance was developing most rapidly. We had 252 children from kindergarten through elementary school practice the walking on stilts 20 minutes a day over a four day period. The number of practice, in which they become able to walk on stilts more than ten steps, decreased with age from six to nine years. From these three studies, we conclude that the best time to learn the crouching start is at about the 13 and 14 years for boy, the over-hand throwing is at about 7 and 8 years for boy, and 8,9 and 10 years for girls, and the walking on stilts is at about 9 years for both sexs.