First off lets start with knowing definition!! =D

Overreaching is a form of short term overtraining that is a part of training with overload and progressive resistance.

Overtraining is when a athlete trains beyond the level that is ideal for maximum benefit.

Staleness occurs when there is a lack of freshness of the sports, feeling bored, and an initial failure of the body to adapt to training.

Burnout is a psychological term for the experience of long-term exhaustion and diminished interest.