How does fitness reduce the risk of injury?

There are several ways in which fitness reduces the risk of different injury's.

1. Increases bone density and strength.
2. Increases muscle fiber strength, your amount of muscle fibers doses not increase after you stop growing.
3. Your tendons also increase in strength.
4. Your also less likely to pull, tear or strain well exercised muscles.
5. Exercise also improves your metabolism which apparently helps your body repair any injury's faster.

I'm no expert, so don't quote me on anything, just telling you what I've been taught by some Olympic coaches and a bit of what I've read or learnt at A level PE which is not fun.

Hope this helps but I'm sure there's other benefits of fitness that I missed.