Post-Injury & Post-Surgical Rehabilitation
Whether it's surgery or a footy injury, the body needs to heal from trauma.
While (depending on the injury) this tends to have a minimum time-frame (there is nothing in the world that will get you doing one-legged squats three days after a knee reconstruction!), we want that recovery to be as uncomplicated and rapid as possible.
Certain activities and behaviours promote tissue repair and 're-abilitation' (as one of my foreign-accented tutors used to say it, and it always struck me as a wonderful mispronunciation that really encapsulates what the word should mean, 'making one "able" again!), while others slow the process down.
An early [as possible] graded return to pre-injury/surgery activities is very important in this, and must be closely supervised to avoid re-aggravating the issue.