I don't want this thread to turn into a debate over helmets and parenting.
I'll just add that I used to be a long distance cyclist. Training rides added up to 300-500 miles per week. I've done several double "centuries" (200 miles). I've also had numerous "offs", including 2 concussions from cycling. Both were before I started wearing a helmet. (Didn't learn the first time)
I had an ER doc ask if I rode my bike faster than I could run. I said of course. He asked if I would put my head down and run into a wall as fast as I could. I said, I may have a concussion, but I'm not stupid. He then asked how come I wouldn't wear a helmet if there was a chance I'd be running my head into a wall (or the ground) 3 or 4 times faster than I can run.
I started wearing a helmet after that and make sure DS wears his.
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