Observations on the reactivity and on the elastic muscular strength of the lower limbs during the age of development.

The aim of this study is to search the relationship between antropometric parameters and muscular strength. During 1994-1996 we consider 563 children, 286 boys and 277 girls, age between 10 and 12 years. The group is evaluated by a jump test (drop jump test of C. Bosco): we pay particular attention to contact time to the floor (TC), to fly time (TV) and to different strategies of jump. Antropometric parameters analysed are height, weight, limb's and trunk's length. The results is analysed and compared each other with statistic analysis (variance e regression, significative value for p<0.05). No significant difference between male and female, in each age we consider. The only improve in TC and the higher value in TV is observed in both sport groups at the age of 12, when limbs are lengthier than trunk. The performance of eleven years old group (boys and girls) are worse than the other ones. In conclusion, in according to the literature, neuromotory ability of children practising sport is significantly better than sedentary groups, even if each subject uses, during jump, a different postural control and strategy of motion.