The survey also presented recommendations for the age at which a player could learn different types of pitches. These are listed below.
Survey - Age Recommendation for Learning Various Pitches
8 - 10
10 - 13
14 - 16
15 - 18
16 - 18
16 - 18
17 - 19
Pitch Count Plus Other Factors
Other factors to take into account as you determine, "How many pitches should I allow my player to pitch?".
Some Additional ASMI Survey Conclusions:
A pitcher should be limited to two appearances per week.
Participation in multiple leagues, playing other positions, and practice should be considered when defining and regulating rest.
Improper technique is a major factor in injury potential.
Conditioning of the throwing arm and entire body can reduce a young pitcher's risk of injury.
While the number of pitches should be limited, the young athlete should be encouraged to throw. This includes playing catch, playing other positions besides pitcher, and practicing pitching. When symptoms of arm discomfort or fatigue arise, longer periods of rest are recommended.