COMPARISON OF MUSCLE PATTERNING IN THE OVERARM THROW AND TENNIS SERVE

The muscular patterning of three skilled throwers who were less skilled servers, three skilled servers who were less skilled throwers, and three individuals skilled in both sport skills, was studied by means of electromyography and tri-plane cinematography during performances of the throw and serve. Surface electrodes were used to record electrical activity from two trunk, four shoulder girdle, and four shoulder joint muscles. Regardless of skill level, the nine female subjects used common joint and segment movements and employed, with minor exceptions, the same number of muscles during late preparatory and force production phases in the two skills. However, for the two skills, there were differences in the duration during which the muscles were active. The serve took longer to perform and involved a different sequential coordination of muscular activity than did the throw. Differences in muscle patterning between the two skills were greater during the force production phase in individuals judged to be skilled in both sport skills. The temporal differences between the two overarm skills suggested that, if performers can perceive time differences between 200 to 800 mseconds, then reference to or practice in the throw may not be a good method to gain expertise in the serve. © 1979 Taylor 8 Francis Group, LLC.