An athlete completes a return-to-sport testing battery. Strength looks good. Hop testing looks good. Limb symmetry is above 90%. The athlete passes—and everyone assumes that means the athlete is ready.

Then the athlete gets hurt again.

In this solo episode, Lou Fullenkamp examines why passing return-to-sport testing does not guarantee safety. He breaks down the limitations of limb symmetry index, explains why the uninvolved limb can be an unreliable reference point, and explores what controlled hop and strength tests may fail to capture about actual sport.

The episode also examines fatigue, unpredictability, cognitive load, psychological readiness, and the often poorly managed transition between discharge from physical therapy and full reintegration into training and competition.

Testing remains valuable. The problem is the certainty we attach to it.

Instead of asking only, “Did the athlete pass?” clinicians should also ask, “What does this testing tell us—and what does it still leave unanswered?”