 Thank you very much. I'm James O'Keefe. I'm a cardiologist from Kansas City. I'm going to talk to you about potential damage from excessive, endurance, extreme, cardiovascular exercise. So this is a topic that is very controversial. And I'm coming to you as a lifelong exercise aficionado. I love to exercise. I'm sort of a hyperactive kid. It's one of the reasons I went into cardiology in the first place. I really love exercise. It calms me down. And then when I'm in cardiology, I see all the problems that come up when people don't exercise. So to us, to cardiologists, this is sacrilege. And I've gotten a lot of feedback. I mean, a lot of negative flashback. We've published two or three papers in the last two or three months on this issue. But the science is really coalescing. And it's telling a really interesting story that I think you'll find interesting. So let's go back to the beginning of the marathon. Fadipides was the first marathoner. He was a Greek herald messenger runner and he ran for a living. He didn't use a horse. He would run messages back and forth. He was about 40 years of age. There was a big war going on, the Greco-Persian War, about 490 B.C. And it would have been a busy time. It was towards the end of the war and things were getting intense. And he was running 150 miles, about 48 hours, the 48 hours before the day of the first marathon. And on the day of the first marathon, he got up and he was a little sore and he was a little tired. But it's time to go to work. Well, it turns out that the Greeks beat the Persians that day in a battlefield outside of Marathon. And so he ran from Marathon back to Athens, which was about 26 miles. And when he got there, he said, victory is ours. He collapsed and died. Not an auspicious debut for the marathon, right? People seemed to forget that. Then they actually became a race in 1896 in the first modern Olympiad. And they decided, well, let's do a long distance race. And why not commemorate Fidipides with the marathon? And it's a strange place in America these days. In the last 30 years, while obesity has tripled, the number of people running a marathon has gone up 20-fold. Kind of like the old Dickens novel. It was the best of times. It was the worst of times. We tend to embrace extremes in America. And Marathon running, Hippocrates was one of the contemporaries of Fidipides. A few years younger. But I wonder if this was not influenced him, one of his quotes. He was the father of medicine, by the way, modern medicine. He says, the right amount of nourishment and exercise, not too little, not too much, is the safest way to health. He figured this out 2,500 years ago. This is not rocket science. This is perfect common sense. You would know this if you've ever run a marathon. Have you ever run a marathon? Yeah, most people, yeah. So I ran a marathon when I was in medical school a long time ago. And I was miserable. And I was like 23 at the time. My knees were sore. I was sort of hypothermic and confused by the end of it. And I thought, you know, even though I loved exercise, I thought this is not my favorite kind of exercise. I haven't run one since. And although I have probably been exercising too much, as it turns out. I'll tell you about that later. But so there's been these, you know, rash of marathon deaths that have runners on edge. And it's interesting to notice that 50% of the deaths in a marathon. And I went back up to say deaths in the marathon are not the big problem. That's sort of like the, you know, the tip of the iceberg. The bigger problem is this is not ideal for cardiovascular health or for longevity. This is kind of like the obvious catastrophe. And by the way, 50% of the deaths of these long-distance races like full-distance triathlons or marathons paradoxically occur in the last mile, the last few minutes of the race. I haven't really figured out why that is, but it probably has something to do with cardiac fatigue and then a burst of catecholamines, adrenaline, towards the end, you know, and it triggers an arrhythmia. But in any event, one of my good friends, like a lot of my social network is composed of people who over-exercise. But anyway, one of them is a girl named Megan. They're in the middle. And she was like one of the top female triathlons in America last year. And, you know, she's doing well this year, too. But she's 30, and I've been telling Megan, well, last year, for example, she did like 10 real high-level triathlons, mostly one full-distance triathlon and mostly were Olympic distance, about two hours of hammering it. So she won the female, overall female, in about six of them, and the other six, she collapsed before the end of the race. You know, so they start testing her up, and, you know, she can generate just ridiculously high, hyperthermia temperatures. I mean, she's just basically, I told Megan, you know, we got to, you got to find a better outlet for your over-achieving, you know, kind of nature. And she admits, and, you know, she's going to quit this year. But in any event, anybody ever had born to run? This is like the Bible. I read this, too. This is the Bible. And even when I read it out, you know, this is glorifying ultra-distance running. It's really accurate. It's saying that we're born to run. In fact, we're born to walk. The latest science would suggest we're really born to walk, and running was meant to do on an intermittent, you know, chasing a monkey for a few hundred yards or running away from a tiger for a quarter of a mile or something. But under no circumstances would we be running 26 miles at a time. Not in our paleolithic ancestry. So the star of born to run is going to be Micah Tru, the mythic epic runner who'd run a hundred miles in a day and in the Copper Canyons with the Tahirumara Indians in northern Mexico. And so he died at the end of March this year. He was out on a little 12-mile training run, which is like a walk in the park for him in sort of the backwoods in the mountains of New Mexico. Took him four days to find his body. When they found it, they did an autopsy, and they said, he died of idiopathic cardiomyopathy, which in cardiac language means a weak, thickened, stiff heart muscle, a diseased heart of unknown cause. But I looked at the pathology report and, in fact, his heart was a poster child for what we've dubbed Phadipides cardiomyopathy. Okay? His heart was enlarged, stiff, thick, especially the right ventricle and the two atrio. Stiff, thick, sort of like accelerated aging. His heart was irritable. He was out on a training run. He was 58 years of age. That's when this starts kicking in. You can get away with it when you're 15 or 20 or 25 or 30 or 35 or 40. Things start, you know, happening around 40, 45. It's about when I started noticing palpitations and problems when I'd really hammer it. And in fact, I have a bunch of friends. One of my best friends is a cardiologist from down in New Orleans. And he has been running 50 miles a week forever. Cardiologists tend to be, you know, exercise addicts. But, and these days when he goes out to do even a 5K or 10K run, he has to take fleckenheit which is an anti-rhythm because it gets atrial fibrillation just before it starts. Atrial fibrillation is epidemic among endurance athletes. A lot of them don't even know they're having it. It's a rapid irregular heart rate that can predispose to stroke. So there are signals out there and that this might not be healthy. But in any event there's no doubt, and this is what I really want to make sure you understand, is that exercise is among the very most important things you can do for your health. Let's put that right out there right now. This is not an excuse to sit on the couch. Okay? This, you know, this is fitness. This is like fitness level better than 10 mats. If you can skip rope you can do 10 mats. If you can jog at 6 miles an hour that's about 10 mats. Okay? A 10 minute mile. If you can do that that plateaus out. You have half the mortality over the next 20 years of somebody who can't do 5 mats. Which is a pretty low level exercise. Have a hard time, you know, doing more than two flights of stairs that I'm going to stop and catch your breath. So, but the point is, and we just wrote an article that was published in Lancet on this topic, but this was an article in the same journal of half a million Chinese and this is physical activity for an hour, up to an hour. This is, the red line is moderate activity, light to moderate activity. Vigorous activity is here and even vigorous is less than 10 mats. But you can see this is mortality reduction. You get the most benefit at about 40 to 50 minutes and then there's a rather sort of sudden plateau. And like a lot of things in life, there's a U-curve. This is an upside down U-curve, but it's the U-curve of life. We see it with alcohol. You see it with all sorts of things. You see it with exercise. So, when you're sitting here still you're consuming about 1.5 mats. If you're sleeping it's 1 mat. If you're watching TV it's 1 mat. If you're thinking hard, hopefully like you are now, it's about 1.5 mats. So, it's the resting metabolic rate. It's the energy you're burning to keep the lights on and your furnace running. So, a well-trained athlete can do 25 mats. So, the point is that the dose, like a lot of things makes the poison and exercise benefits, if we had a pill that was exercising a pill, I'd be out of business. Exercise is so great for so many things. I mean, it will have, if you exercise for 30 to 45 minutes a day, sort of moderate to vigorous exercise, it'll cut your risk of dementia, early death, diabetes, heart disease, stroke, in half. Not to mention depression and improving quality of life. In half there's nothing else that gives you those kinds of benefits. But like any potent drug, too little is not enough. If you get up and just walk back and forth to the refrigerator from time to time, that's not going to do it. You need to get out and get like 20 minutes of exercise. Too much medicine can be harmful. This is a potent drug. You go out and exercise for 6 or 10 hours a day, you're going to be in trouble. It might take a decade or two or three or four, but there's a lot of veteran, extreme endurance athletes out there who are getting in trouble right now because we're just figuring this out. So, the big thing to keep in mind is that there's a totally different thing between performance, peak performance and peak fitness, and exercise for conferring, longevity and overall health. And when you're an athlete you think more is better, harder is better. The more fit I can get, the more I can go. If I can do a full distance triathlon wow, then I know I'm really bulletproof. Wrong. That's the wrong pattern. So, the truth is exercise conferred powerful benefits. The belief is more is better, but we now are coming to understand that exercise conferrs unique and potent benefits, but you can overdo it. Believe me, you can overdo it. All right, so a really interesting study that I was part of and my best friend from down in New Orleans was the lead author on this study was very insightful in this regard. This is the U-shape curve we're talking about and so they looked at 50,000 people in the Cooper Clinic and they followed them for up to 35 years, like 20 years of follow-up. And they found among the runners they had a 19% lower risk of death than the non-runners. But among the runners, those who ran at moderate speeds, moderate distances and moderate frequencies did the best. And so that means 2 to 5 times a week did better than people who did this at once, or 7 times or 6 times. People who ran at speeds around 10 minute miles did the best. That's a pretty slow jog. I mean, you know, if you're a runner you're thinking come on, this is a warm-up, I need to get going. But this is like 20 years of follow-up. This is pretty darned good data. And people who were the distances, what do you think the best distance was? More is not better. It's like how many miles a week you think? Not more than 20. Yeah, 5 to 20. You could run a mile and a half 3 times a week and you'd be at the bottom of that U-curve. It's amazing. And so when you run faster, longer, more often you don't get more benefits. You get less benefits. And if you start running marathons, you start getting to look like the non-exercises with respect to your cardiovascular risk. So, let's just talk a few minutes about what happens when you go out. When you're sitting here, we're talking about METs, your cardiac output is 5 liters a minute. When you go out and you're a trend athlete and you're hammering up a hill full speed or you're running a marathon, you're, this is about a gallon a minute at rest, it's more like 6 times that. A trained athlete, Lance Armstrong Miguel Enderain, you know, the best athletes in the world will generate 35 to 40 liters a minute. This is massive cardiac output and you can train up to do it but after a while it takes its toll and what happens is this volume starts stretching the heart out and the myocardial cells start getting pulled apart. After a few hours and a few decades of doing this every day it starts pulling the muscles apart and causing tears in the muscle and you see troponin elevations in up to 50% of people after a marathon even trained marathoners, half of them. A troponin is what I measure if we come in and you have a heart attack, we measure the troponin to see if there's been heart damage. It's a synachquonone. If you have a high troponin, you've had heart damage. Half of marathoners have heart damage by the end of the race and you can replicate this perfectly well in running rats, running mice. You have to run them for like over an hour day hard, really hard for about four months and you'll see this scar tissue form and it makes the heart. These are MRI images as hard to see but you get these scattered fibrosis in the right ventricle in the atria from this volume sort of stretching the heart causing accelerated aging in the heart. Training goes like this. This is big like a marathon or a full distance triathlon or a 100 mile bike ride through the mountains really hard. The kind of thing where you're really shot afterwards. It takes you days to recover. A really hard effort. What happens is it's an acute reversible injury. Your proponents are up, we did echo in your heart your right ventricle wouldn't be contracting as well. Your age would be a little bigger. By seven to ten days it's all back to normal if you've been recovering. But when you do this you're stronger to these bouts when you're 20 or 30. But when you start to get middle age what happens is you don't fully recover. Before you know it you have this overtrained hypertrophied stiff accelerated aging heart. That's not what we're looking for when we're trying to get in shape right? We don't want an accelerated aging heart and in fact chronic marathoners after 25 these people who've been marathoning for 25 years at least more than one marathon a year for 25 years these are veteran endurance athletes they had twice the coronary plaque in their coronary arteries as sedentary controls. It's not good and there have been three or four studies like this. Again it's very controversial. So not only did they have more plaque but they had twice as many events as the sedentary people. Again I'm not telling you to be sedentary. Remember the bottom of that curve is exercise but you just have to be moderate about it. Atrial fibrillation five-fold increase incidence like in my best friend I see it all the time. I can feel it myself not atrial fibrillation but I can feel my heart getting irritable if I overdo it. If I run too hard run too hard if I don't allow myself to recover and AFib is a big stroke risk. So just to summarize what happens. Strenuous exercise and a lot of this is still evolving so I'm not going to be able to really tack it down and people say well how much and what kind and you know we really don't know the common sense. All right. So high catechol. Your adrenaline is high. Your oxygen is die. You know the volume is massive. You get some damage to the heart. It dilates up. You get cardiac fibrosis. It scars down. It gets rigid. It gets stiff. It gets enlarged. It gets accelerated atherosclerosis. All right. Great book. Gretchen Reynolds, she interviewed me for a New York Times article after this. The first of these articles came out in early June. I was in the Amazon rainforest with my 12 year old daughter and we were hiking and canoeing very moderately in the rainforest. But it was kind of fun because we had there was no electricity around there. We found a link up to a satellite and we were talking to the BBC World News and Gretchen. She published an article in the New York Times about and she has a book recently out about the first 20 minutes saying that exercised better, trains smarter, live longer. And her point is the first 20 minutes you get most of the benefits. 30 to 45 minutes you'll get full benefits from a cardiovascular standpoint. If you want to do more than that you have to this is kind of a funny story. But rats, you can train rats. If you're talking to somebody today who's telling me a story he does research on rodents and they find that they can get rodents to get addicted to running on the wheel and the thing. And they actually set it out in the desert and the mice actually would find it and the wild mice would come and get so that they would get addicted to running on the wheel out in the desert. So I ask people all the time they say, they come to me as a cardiologist and say I want to do a marathon. I say you can do one and cross off your bucket list and find a healthier exercise pattern. And then I say, by the way why are you doing marathons? Because if you're doing it for your health it's like climbing Mount Everest. You do it once, you have boasting rights, move on to something healthier. You're not going to climb Mount Everest once a week or something ridiculous like that thinking that it's good for you. But there is the stress reduction and a lot of people, a lot of their social network is around exercise. But still we need to think about healthier exercise patterns. We did an interview with Ambi Burfoot and he said, well what's this? This is like everything else. It doesn't happen to you when you get out of bed in the morning. I said well, you know first of all, a lot of bad things can't happen when you get out of bed but there are nothing compared to things that happen to people that don't get out of bed. Exercise is good but just like our ancient ancestors did they walked a lot four to ten miles a day. Walk everywhere. Stand up rather than sitting down. Stand up more. Take the stairs every chance you get. That's the kind of exercise we're meant to do. Be a hunter-gatherer and these are Frank Francis' slides by the way. So to summarize I would, and some of this is my intuition based on the research we've done and coalescing the data but there's a lot more to learn admittedly. But I would say if you're going to do strain use exercise which I hardly endorse and I do myself try to limit it to about 45 minutes a day. Up to an hour. Not more than seven hours a week. It's going to be hard especially if you're over 40 or 50 because then you start getting in trouble. Try to spend as much time as you can during the day with moderate light to moderate activities. If you want to do a marathon or a full distance marathon do it once and move on to a healthier exercise pattern and cross train. Swim Pilates, yoga, weight training very important. Fitness is multifaceted. If you're training for life, for longevity for vigor, for mental capacity marathons are not the way to do it. Two hour, four hour, six hour runs and rides are not the way to do it. Exercise for 30, 40 minutes with aerobics then start doing stretching and strength training. Thanks for your attention.