Training too much, which can be bad for your body.
Overtraining can lead to tiredness and not feeling good. It's important to rest and not overtrain.
Examples:
Overtraining can make you feel very tired.
He got sick because of overtraining.
Overtraining is not good for your body.
She learned the hard way about overtraining.
The coach warned us about overtraining.
I felt so bad from overtraining!