Sport specializations with regular, repeated throwing motions cause increase of the shoulder internal rotator muscles produced torques and power in a dominant (prevailing throwing) arm in comparison with a non-dominant arm muscles. An aim of our investigation is to determine an asymmetry of the dynamometry characteristics in the dominant and non-dominant arm muscles, and a relationship between the shoulder rotator muscles isokinetic dynamometry characteristics and the ball throwing speed in the adolescent handball players. Fourteen elite adolescent handball players participated in the investigation detecting by an isokinetic dynamometer system the muscles characteristics in the shoulder external - internal rotation movements. The eccentric – concentric muscles contractions obtained by the dynamometer system partly reproduced the handball throwing movement. The throwing speed of the ball was measured by a reflected light method. A difference between dominant and non-dominant arms muscles characteristics in the concentric contractions is none significant. After the eccentric contractions of the shoulder external rotator muscles the average and maximal power production of the shoulder internal rotator muscles significantly increases. The best correlation is determined between the ball throwing speed and the average power of the internal rotator muscles in concentric contractions after concentric contractions of the external rotator muscles, where r = 0.78 and p = 0.0009.

Latvian Academy of Sports Education Dpt of Anatomy Physiology and Biochemistry

Adaptace svalů ramene na hod u mladých házenkářů

Lit.: 18