Injuries occurred while young will often haunt you when you’re older. For example, I tore a muscle in my back snow skiing and still feel it in the form of weakness and pain in my back. So, try to avoid injuries! Sounds obvious, but it’s easy to forget.
Two things to do: (1) prevent injuries NOW with strengthening and limbering exercises (look them up); (2) do rehab work soon after. Don’t wait until you’re too old!