Broken legs and ankles heal better if you walk on them within weeks

It was hotly debated at the hospital, if my specific case should be operated on or not. Each time I had a checkup, one doctor would say "wait and see" while the other was saying "I can't believe we didn't operate on this".

At any rate, the outcome was as good as if they had operated on it, according to the doc anyway. Nice of them to test it out on me!

More related to this though, I have broken both my collarbones, the first time I had little direction and just held my arm still for 2-3 months. It took forever to heal, and my arm atrophied significantly. The second time, similar severity. I was guided through rehab and I was back using my arm within the first month, very little atrophy.

A lot of the injury risk when mountain biking is reasonably easily mitigated by controlling your speed and walking the bike through terrain that's above your skill level. There was a report out of British Columbia a few months ago about injury rates, and they were high, but BC is also a major downhill trail region.

Certainly, compared to road cycling, I know more people with major injuries from being hit by cars than from crashing solo on a mountain bike. And for my own cycling injuries - a few concussions, the worst of which was on the road bike (during a race) and a few torn rotator cuffs/mild AC joint separations.