One of my coworkers had a bit of a bike accident. Pretty much exactly the same one I had a few years prior. Riding along, front wheel stops instantly, bike pivots around your front axle, and any residual energy is dissipated between the rider's head and the ground. So he walked in with a scraped up face. And one of my coworkers mentions that he's suddenly a lot less interested in biking. And so I told him that you can always die on your couch of a massive heart attack at age 40 if biking scares you too much.
Now, some people die, for no reasonably explicable reason, in their forties of a heart attack. And.. well, Jim Fixx popularized jogging and then died at age 52 of a massive heart attack. (And, besides, his dad died in his forties, so you can assume that it might have helped him some) One of my friends from high school died suddenly a few years ago, leaving a wife and kids, which still gets to me.
There's stupid unreasonable risks. Biking downhill at high speeds without a helmet. Scrimping on safety gear for a motorcycle. Trying to fly a hang glider without taking lessons on how to fly it. Going on a solo hike in the wilderness without even telling somebody to call the park rangers if you haven't called back before a certain date and time. Things like that. For most things, there's a reasonable amount of preparedness and safety gear that can be acquired to make them reasonably safe so you can leave the dirty job of hacking off your own arm with a pocketknife because you are so stupid as to go on a solo hike without telling anybody to the idiots. Avoid stupidity, and you've already done a pretty good job of not shortening your lifespan.
But being so seriously afraid of injury, being so ruled by your fears that you are unable to do anything other than sit inside your little cage all day... well, that's pretty much dying before you are actually dead.
As it turns out, if you take into account the risk of being hit by cars and the damage to your lungs and circulatory system from micro-particulate exhaust particles output by cars and things like that... the benefits of biking outweigh the benefits of hiding in fear on your couch with a nice BluRay playing.
Plus, real life is far more fun than TV. I can show you the pictures of a row of cyclists on a long ride towards Point Reyes.. but you'd have to be part of it to get the wind, the smells, the emotional impact of being with real people instead of TV characters, the feeling of accomplishment to really appreciate it. It's not even the same if you drive the same roads.
It also turns out that cycling gets safer when more people are doing it. Largely because cars suddenly realize they need to keep an eye out for cyclists instead of assuming that there won't be any cyclists.
So, yeah, sometimes it just happens that you die in your twenties or thirties or forties. And that's a tragedy. But I still think that you'll do a better job of living your life if you do it on your bike instead of on your couch.