Question

which sports - training principle refers to how long the body takes to heal and rest before being ready to \work\ again?

injury prevention
frequency
recovery period
specificity

Explanation:

In sports - training, the recovery period is the time the body needs to heal and rest before resuming activity. Injury prevention is about avoiding injuries, frequency is how often one trains, and specificity is about training relevant to a particular sport or activity.

Answer:

recovery period