Book Review: Strength Deficit by Tim Caron — Why Most Coaches Are Training Athletes Wrong
Tim Caron’s Strength Deficit is one of the most important and, frankly, most challenging books a strength and conditioning coach can read today. In a field obsessed with numbers and weight-room achievements, Caron delivers a sharp, necessary correction: strength alone is meaningless if the athlete cannot express it in sport. The central concept of the book, “strength deficit,” represents the difference between an athlete’s maximal force capacity and the force they can access during actual performance. It’s a deceptively simple idea with massive implications. Many programs create incredibly strong athletes who cannot accelerate, jump, change direction, or produce force at sport-specific velocities. Caron argues that this disconnect, the inability to use strength, is the silent training failure coaches often miss.
One of the book’s strengths is how aggressively it challenges dogma. Caron dismantles the idea that bigger lifts automatically equal better athletes. He pushes coaches to stop pursuing numbers for the sake of numbers and instead evaluate whether their training is producing the qualities that actually matter. This requires better testing, and Caron provides a strong framework for doing so: force-velocity profiling, the isometric mid-thigh pull, jump testing, and velocity-based training all play a central role in identifying whether an athlete is strong-but-slow, weak-but-elastic, strong-and-fast, or simply lacking foundational qualities. The message is clear. You cannot guess an athlete’s strength deficit. You must measure it.
From there, Caron offers a practical and nuanced blueprint for training. If an athlete is strong but slow, heavy barbell work is not only unnecessary — it’s counterproductive. They need speed-strength, plyometrics, elasticity work, and low-load, high-velocity training. If an athlete is weak and slow, they need basic strength, hypertrophy, and structural development. If an athlete is strong and fast, you protect those qualities, not bury them under junk volume. And if an athlete is elastic but weak (rare, but real), their training becomes extremely targeted. The value of the book lies not just in defining strength deficit but in showing coaches how to apply the concept across scenarios.
Another standout theme is Caron’s repeated insistence that strength expression is a skill, not an automatic byproduct of lifting weights. Too many coaches assume that a stronger athlete is automatically a more explosive athlete, but Caron’s perspective, supported by both research and real-world experience, is that athletes must learn how to coordinate force, time force, and direct force efficiently. Intent, movement quality, and velocity zones all matter. This is the reason the strongest athlete in the weight room almost never becomes the best athlete on the court or field. Transfer doesn’t happen by accident; it must be coached deliberately.
The book shines in its ability to elevate the conversation within the S&C community. Caron’s writing pushes coaches to think deeper and move beyond cookie-cutter programming. It provides clear principles that can reshape how we approach athlete profiling and individualized programming. However, it is not a beginner's text. Coaches without a background in biomechanics, force-velocity relationships, or sport science may find it dense, especially in the earlier chapters. Some examples lean toward elite or professional environments, which can make translation to the high school setting challenging. Though the concepts themselves absolutely scale down. The book also would have benefited from more real-world case studies to help bridge theory into daily practice.
Despite those limitations, Strength Deficit is essential reading for any serious performance coach, sport scientist, or evidence-driven practitioner. It forces reflection: Are you building athletes who are strong on the field or just strong on paper? Caron’s thesis, that many athletes don’t need more strength but need better access to the strength they already have, is both accurate and overdue. In a field where tradition often outweighs science, this book brings clarity, precision, and a refreshing honesty. It will challenge your assumptions and likely change your programming. And that’s exactly why every S&C coach should read it.
