When I get a runner in with a chronic running injury, something like sore knees, shin splints or back pain (brought on by running) then my course of action will probably be to do something like strength training.
I say this not because the injury is due to some nonsense diagnosis like weak glutes or core, I may decide to do a yoga based, stretchy type block of sessions but not because the (insert random muscle here) is too right and needs a magical release, I just do something that is not running because the evidence would suggest that most running injuries tend to come from overuse and if I take running away from a runner I need to be ready to replace it with something else.
This little space of training that definitely isn’t running is where the magic happens. I use other forms of training to give my client skills they can potentially transfer into their running, I can increase their ability to create tension in their core, I can develop their movement skills so they have more power in short ranges, I may give certain joints more range, some less depending on the client so when I start introduce running when the pain subsides or the injury heals my client is not only more resilient to further injuries but usually performing at a higher level than before they were injured.
So why wait till you get injured to get a performance enhancement?