The Highway

Consider the lanes on a highway. 
The lane for a healthy athlete is called training. The lane for an injured athlete is called rehab. It’s the same highway. Same destination. 
Along the path, the injured athlete will still merge onto the training lane at times, then merge back when necessary. But again, they’re still moving forward toward the destination.

Training - keeping someone fit and prepared. 
Rehab - keeping someone fit and prepared, while simultaneously recovering.

The destination is always the same.