Jun 15, 2018

Interviewer: Running from a doctor's perspective, that's next on The Scope.

Announcer: This is "From The Front Lines" with emergency room physician, Dr. Troy Madsen on The Scope. On The Scope.

Interviewer: When emergency room doctor, Troy Madsen, was thinking about running as his main exercise a few years ago, he was concerned about how it would affect his knees. So he did the research like any good doctor would do. And Dr. Madsen, what did you find out?

Dr. Madsen: Well, you know, like you said, my concern in running was, "Okay, great. I'm going to start running more." I said I'm going to run every day, do a couple miles every day, go from there, but in 10 years, I'm going to need a knee replacement. This is what I thought. This was what I grew up hearing. This is what people said. So I said to myself, you know, "I work in medicine, certainly I can look and see what kind of evidence there is for this. Are there any studies that have been done that show that runners have a much higher risk of needing knee replacements?" So the big concern here would be that you run a lot, you wear down the cartilage in your knees, you get osteoarthritis, which is bone on bone, and then at that point, it hurts too much, you need to have your knees replaced.

So it's a tough thing to study. You know, ideally, you would take a group of people and say, "You guys are going to run every day, you guys aren't. And then 10 years, we're going to see how your knees are doing." You can't do that. It's not practical. So you really just have to rely on people reporting how many knee issues they've had. Look at runners, look at non-runners.

Interestingly enough, at the time I looked, there were a few studies that had been done looking at this, and just this month, an editorial came out in the British Medical Journal that addressed exactly this question. So they summarize all the research that is out there. The bottom line is there is no convincing evidence that will tell you that runners have a higher risk of knee osteoarthritis and knee replacements.

The only thing they found, they said, okay, one study showed that in elite runners, they had a higher incidence of osteoarthritis where it was this bone on bone. This was one study that was done in the early 1990s. These were elite runners, meaning runners who had competed in Olympic marathons, and they had a little bit higher risk of this issue. I found studies that actually suggested in runners, they're 50% less likely to have any issues, meaning that maybe this running is actually helping the knees potentially helping build this cartilage up. You know, certainly, if you're having other injuries like ACL injuries or tearing ligaments, things like that, that's a different issue.

But just the whole wear and tear of running or this idea that you're just tearing your knees up, I can't find anything convincing that says, "Yeah, you're tearing your knees up, you're going to get bone-on-bone knees, and then in 10 years, you are going to need a knee replacement."

Interviewer: So had you found evidence to the contrary, would you be a runner right now?

Dr. Madsen: It's a great question. I don't know.

Interviewer: I'm trying to figure out if you're putting your money where your mouth is on this deal.

Dr. Madsen: Yeah, you know, at the time, and I think for a long time, that was my excuse for not running. I'll tell you the reason I ran is because my wife made me commit to run a marathon because we're moving, and that was part of the deal, "If we're moving, you have to run a marathon." I think she thought I was going to say that there's no way I'm going to run a marathon, but I committed to do it, and I've kept running since then. I think partly knowing that, "Hey, you know, this is a great exercise. It's a great sport. It's a great life-long sport. And the whole knee issue, I'm convinced that, you know, based on the evidence I can find that running isn't going to tear your knees up." I just can't find anything that absolutely says, "Yeah, you're going to have lots of knee problems because of this."

Interviewer: What about like somebody's weight or other issues like that? How is that taken into account in these studies?

Dr. Madsen: Yeah, it's tough. Again, these are not ideal studies.

Interviewer: Sure.

Dr. Madsen: I mean, they're small studies. They're combining these studies to create what's called a meta-analysis where you combine data from lots of different studies. I don't know that they can really control for those factors for weight and look at a person's weight. Because you're talking about people who've been running for 20 years, can you account for their weight 20 years ago versus now? What different effects are there? I don't even have an answer.

Interviewer: Yeah, yeah. I would imagine, too, something else maybe to keep in mind. So I think this is good that if running is something that you do, that's great, continue to do it. If it's something you want to do, there doesn't seem to be a lot of compelling evidence it's going to cause knee issues. But I'd imagine it would be smart to be safe and, you know, make sure that you're in with a reasonable weight, and maybe even make sure that you're running form is good, that you're not heel striking and doing some of those sorts of things. Because the runners in the study conceivably would be doing those things.

Dr. Madsen: Exactly. You don't want to force yourself into a sport. You want to make sure your heart is in good shape, that you're going to be able to handle it. Don't just go off the couch and go put in seven or eight miles. Like you said, you've got to consider all those factors. Find a sport you enjoy. But I think the bottom line from this is if you enjoy running, don't tell yourself you can't run or you can't run more because you're going to have major knee problems down the road. I just can't find anything that suggests that's the case.

Interviewer: And since you started years back, when you first started running, when you did this research, you've since run marathons, and how do the knees feel?

Dr. Madsen: Knees are great. Don't ask me that question after a marathon, but today the knees feel good. You know, after long runs, there's always the aches and pains.

Interviewer: Yeah, but not knees, right? It's usually muscular or . . .

Dr. Madsen: Yeah, it's usually muscular, it is. It is not the knees so much. Well, I'll take that back. I'd say usually about mile 24, 25, everything hurts.

Interviewer: Sure.

Dr. Madsen: And I'm telling myself, "I will never do this again." But, you know, you give it a day, you start to feel a little better, and then you're back at it.

Interviewer: And then for individuals that maybe currently run and they're thinking about wanting to run a little bit more, maybe they're kind of in this three to five-mile range, and they're afraid to go beyond that. Again, the research shows that probably not going to negatively affect you?

Dr. Madsen: Exactly. I think that's the big take home. But at the same time, keep in mind that if you're happy just doing three to five miles, keep doing it. You're getting the health benefits. And that's a whole different discussion. But if you're doing three to five miles, three times a week, you're doing great. And if you like it, if you're happy with it, keep doing it. If you want to increase those miles, maybe do a half marathon or something, feel free to do it.

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