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Fitness & Athletic Development

Build the athlete, not just the player.

The physical side of development, done right. How to build strength, speed, power, and movement for baseball and softball players from first-ball through the pros. Bodyweight-first, matched to age and maturity, and grounded in the research, not the trends.

Baseball & Softball Ages 6 to Pro Bodyweight First Evidence Based
The Playbook

The Development Guide

The full, plain-language guide to physical development at every age. What to build, what to avoid, and the three things that matter most. The thinking behind everything here.

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Quick Tool

Stage Finder

Answer two quick questions and see what good, safe training looks like for your athlete's stage, and what to avoid. A guide for understanding, not a prescription.

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The three rules that govern every age

Educational resource only. Not medical advice. These pages explain general principles of youth athletic development. They are not a personalized training prescription and do not replace a qualified strength coach, athletic trainer, or physician who can see your athlete. Around a growth spurt or with any pain, check with a professional first.