I. Cinematographical analysis of fast ball pitches of 6 Little League baseball pitchers (aged 9 to 11 years old) indicated that their pitched ball speeds, ranging from 19.2 m/sec to 28.2 m/sec, were similar to the values previously reported for non-athletic male adults. However, the peak torques during maximal elbow extension (constant angular velocity = 210°/sec) were the values from 12.03 Nm by 9-year-old players to 15.32 Nm by 12-years-old players and were less than half of that by university baseball players (32.10 Nm). Therefore, although Little league baseball players indicated high pitching performance, they were considered to have relatively low level of muscular output.
II. In order to identify the difference in the pitching motions between fast and curve ball pitches, muscle activations and joint angular velocities were recorded from the upper extremity of a university baseball pitcher. The following points were peculiar to the pitching motion of curve ball pitch compared to that of fast ball pitch;
1) Greater elbow flexion was observed sooner prior to ball release.
2) Angular velocity of wrist flexion was more rapidly increased after ball release.
3) Both m. biceps brachii and m. brachioradialis were markedly activated after ball release.

DESCENTE SPORTS SCIENCE Vol.1/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE