Directly from ASMI's position statement on recommendations for youth pitchers. See #8:
Thus, the recommendations for preventing injuries in youth baseball pitchers are:
- Watch and respond to signs of fatigue (such as decreased ball velocity, decreased accuracy, upright trunk during pitching, dropped elbow during pitching, or increased time between pitches). If a youth pitcher complains of fatigue or looks fatigued, let him rest from pitching and other throwing.
- No overhead throwing of any kind for at least 2-3 months per year (4 months is preferred). No competitive baseball pitching for at least 4 months per year.
- Do not pitch more than 100 innings in games in any calendar year.
- Follow limits for pitch counts and days rest.
- Avoid pitching on multiple teams with overlapping seasons.
- Learn good throwing mechanics as soon as possible. The first steps should be to learn, in order: 1) basic throwing, 2) fastball pitching, 3) change-up pitching.
- Avoid using radar guns.
- A pitcher should not also be a catcher for his team. The pitcher-catcher combination results in many throws and may increase the risk of injury.
- If a pitcher complains of pain in his elbow or shoulder, discontinue pitching until evaluated by a sports medicine physician. Inspire youth pitchers to have fun playing baseball and other sports. Participation and enjoyment of various physical activities will increase the youth's athleticism and interest in sports.