Every time I hear someone say that running is bad for my knees, I want to knee them where it hurts to prove that my knees are actually just fine, thankyouverymuch.

But then other days, weird stuff happens. Meteorites fall on earth, a new Die Hard movie comes out, it rains spiders somewhere, the pope resigns like being the pope is just another office job, and I… I wake up all understanding and nice and stuff. On those weird days, I try to make sense of where those ideas come from.

It’s really easy to assume running is bad for your knees. Look at those hot runners pounding the ground like nobody’s business. It looks like hard work and those knees are getting the impact. But guess what? That’s what they’re designed to do.

Here’s a quick list of things that are bad for your knees: endless hours of sitting on the couch watching episodes of the Real Housewives of Whogivesacrap, getting attacked by a swarm of bees and having some of them sting your knees (now say that last one really fast), getting into a bar fight and getting a bullet right on the knee cap, wrestling a bear and having the bear grab you by the knees and crushing your knee caps with its own giant bear paws. I could go on but I think I’ve made my point. Notice anything missing from that list? Exactly.

What really gets me is that it’s always those with no real health credentials that seem to have instant PhDs in this topic – they are always the outspoken, know-it-all ones. If it’s okay with you, I’m only going to take medical advice from people who actually know what they’re talking about. Like my doctor, for example, who actually went to medical school and who has his own medical practice and who has even run a marathon. If the extent of your medical knowledge comes from about.com type sites or hours of watching Dr Oz, then I suggest you keep that advice to yourself because you might just be causing more harm than good.

The fact is that your body is not designed to be sitting around doing nothing. Moreover, doing that is precisely what causes damage to every single bone, tendon and muscle. Modern society has made it all really easy for us. Don’t get me wrong, I’d also love to have a robot that can pick up my ice cream from the freezer and bring it to me while I sit on the couch watching re-runs of How I Met Your Mother, with my knees safely tucked under the blankets. But if I ever get a robot like that (please, science, please please please!), then it better come coded with a function to also automatically turn on and off the oxygen mask I’ll soon be needing to help me breathe.

Exercise is not bad for you and I’m always shocked to find people spreading this stupid idea around, especially when obesity is at an all-time high (and you can’t tell me that carrying all the extra weight from all those burgers isn’t bad for your knees). “Oh but remember so and so, who died right after the marathon?” Hmm, yeah, thanks for that reminder. Also, exercise-related deaths are publicized precisely because they’re a rare occurrence. Don’t quote me on this statistic, since, other than my kilometers on the road, I have the health credentials of a hedgehog who drank too much Makers Mark (before they started diluting the stuff) but I’m pretty sure you are far more likely to die in your sleep than while exercising.

The key to this is the same key to everything else in life: moderation. A glass of wine won’t kill you (unless it gets thrown at you really hard, maybe). A lifetime as a raging alcoholic will probably cause a fair amount of damage. A marathon won’t kill you. Run double-digit miles every day for the rest of your life without a moment’s rest and, yeah, you might actually collapse.

If done in moderation, running is pretty much the best cardiovascular exercise you can possibly get. Not only that, your knees, like everything else in your body, can get stronger through exercise, if exercise is combined with the right amount of rest. It’s that rest period that strengthens everything, it completes the workout and makes sure you get the full effects of the exercise (and I’m not just saying this because I’m on day #2 of not running).

When was the last time you heard of research showing you that couch potatoes live longer and healthier lives than people who exercise? I don’t watch much daytime TV but I’m pretty sure that “Steve dramatically improved his health just by spending a mere two hours a day sitting down with a bowl of chips” isn’t a sentence that comes up very often. So where do these ideas come from?

Running looks like hard work (because it is). Hard work scares people. Except people don’t like admitting they’re scared of hard work so they come up with other reasons why they’re not doing it. “I’d love to run but it’s so bad for the knees” is a cop out. If you can’t run because you already have knee issues, that’s a different problem – but, in that case, running can’t be blamed for it anyway. It’s easier for people to find an excuse and pretend that there’s a higher reason they choose not to exercise, aside from their own laziness.

If it turns out that, by some miracle, they are right and all logical thinking along with everything we know about the human condition is actually flawed, then that’s okay. I’d rather live a long life with bad knees than a life that gets cut short because my sedentary lifestyle translated into heart and lung problems.

Now I better go get my own ice cream since science is stalling on that robot idea.

(If you want to read more from people who actually know what they’re talking about, I suggest reading stuff like this or this.)