When athletes or soldiers train too much, their bodies can go into overtraining mode, which causes hidden inflammation that weakens the immune system, makes muscles shrink, messes with blood sugar, and makes them more likely to get sick.

Paralympic athletes who train too much without enough rest or fuel might be more likely to get stress injuries in their bones, especially if they do endurance sports like racing or long-distance events.

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.

Overtraining in athletes might actually show up as low energy from sports, meaning that 'low energy' could just be one way overtraining looks, not a totally different problem.

If athletes push themselves too hard for too long without enough rest, they can develop a serious condition called overtraining syndrome, where their performance gets worse and just won't improve — even after taking time off.

To diagnose overtraining in athletes, doctors need to rule out other health issues like low nutrients, infections, or energy deficiency, because those can cause similar symptoms and often happen at the same time as overtraining.