6–8 minutes, the same every time. About a third fewer injuries.

Two or three times a week, add 6–8 minutes of landing control, single-leg balance, hamstring and groin strength, and shoulder and wrist prep. It only works if people actually do it, so keep it short and the same every time.
S Evidence: strong. Large trials or many studies, pointing the same way.
E Evidence: built from practice. What works for coaches and practitioners. Labelled that way.
Ding et al. 2022 · Al Attar & Alshehri 2019 (youth sports: injuries cut by about a third). Calisthenics hasn't been studied, so this is by analogy.
Not medical, legal or financial advice.
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