Doctors can't use a single blood test or scan to diagnose overtraining — instead, they have to rule out other health problems and see if an athlete's performance keeps dropping for no clear reason.

Overtraining isn't just being tired — it's when an athlete's body stops working properly and performance drops for a long time, even after resting, and it's different from regular burnout that goes away in a few weeks.

There's no single blood test or clear sign that doctors can use to diagnose overtraining. Instead, they rely on a mix of how you feel (like mood and fatigue) and lab tests (like hormones and inflammation), but none of these are very accurate on their own.

There's no single blood test or clear sign that can definitively tell if someone has overtraining syndrome. Doctors instead use a mix of mood surveys and lab tests like cortisol or testosterone, but none of these are very accurate on their own.

Some scores that combine health, hormone, and body measurements might help tell the difference between male athletes who are overtrained and those who aren’t — but right now, there’s only one small study showing this.

Most studies show that when athletes push too hard and start showing signs of overtraining, they're often not eating enough calories or carbs to fuel their bodies.