Development

Your Pitcher Throws More Than You Think

As summer ball ends and fall ball begins, the biggest arm-health risk isn't a single outing — it's the throwing volume nobody is counting.

August 10, 2026 · 5 min read
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Finding of the Month

The velocity era is measurable — and the danger starts young

Average MLB fastball velocity
91.3 mph
2008
94.2 mph
2024
MLB average four-seam velocity, league / Statcast data.
Most UCL injuries occur between ages 15–19 — not in the majors.

Average major-league fastball velocity has climbed nearly three miles per hour in fifteen years, and amateur arms are chasing it. But the research keeps pointing to where the damage actually happens: a majority of UCL (Tommy John) injuries occur between ages 15 and 19, when bones outgrow the ligaments trying to stabilize them. Our coverage lays out the realistic timeline for adding velocity without paying that price.

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