On Wednesday, I spoke with Mebrahtom Keflezighi, perhaps the most successful American marathoner of all time. He won the New York City marathon in 2009 and the Boston Marathon in 2014. He won an Olympic silver medal and was internationally competitive until the age of 42, in a sport where people tend to peak much younger than that. On Monday, he will be the grand marshall of the Boston Marathon. Keflezighi possesses a wealth of running wisdom, much of which he shares in his book 26 Marathons. We spoke mainly about the science of running fast in difficult conditions and about how to keep a career going as one ages.

Nicholas Thompson: As someone who ran lots of difficult courses and many marathons, tell me the factors that mattered most to you in a course?

Mebrahtom Keflezighi: The first thing is that a marathon is going to hurt no matter what. People need to understand that. But you want to hurt as late as possible, and knowing the course helps. If you know the course is going to be hilly, then you need to do more hills training in your preparation. You should also visualize yourself doing hills. When you come to a hill, what do you need to do? You need to do short strides, more arm action, lean forward a little bit, and conquer it. If you do that for two months or three months, it becomes second nature.

NT: What about weather? How much would you focus on the weather forecast in the days before one of your races?

MK: I mean, the weather’s the weather. I was just talking to Geoffrey Kirui, who won the Boston Marathon two years ago, and he was asking me for some advice: the weather, this and that. And I was like, “You know, it’s going to rain on everybody!”

What do I need to do to run myself really well in nasty, wet conditions? I don’t want to be cold or get hypothermia. So I need to layer up. What material do I need? I need to wear a beanie, or I need to wear a cap, or I need to wear both. So I worry about that versus, “Oh man, it’s going to be bad weather.”

NT: But when you think about your splits, how much are you adjusting them for the weather? If your plan is to go out at 5 minutes per mile or 4:55, and then you know it’s a rainy day or a windy day or a hot day, do you and your coach say, “OK, let's go out at 5:05”?

MK: At the elite level, you go with the group. If they go out on 4:50, you have no choice but to go at 4:50. If just one person goes at 4:50, you’re like, “You know what, I can catch them later.” But if six people go, you know they’re going to help each other. So three of them might come back and three of them might survive. So you have to make that conscious decision. You know the coach only can get you ready for the starting line.

NT: What were you thinking about the course and weather when you made your big move the year you won, in 2014, one year after the Boston bombing?

MK: In preparation, and in my visualization, I thought it was going to come down to the last 500, 600 meters on Boylston Street. But when I made that conscious decision about the course, was when Joseph Boit and myself were running, we separated ourselves from mile 5 to 8 and we wondered, why are they letting us go? Personally, I’m thinking, “Hey, I won New York; I won a silver medal; you’re making a mistake.” And then I just said, you know what, I need to control my destiny here. I know the course, and I need to monitor my pace and conquer the hills one hill at a time by myself. I ran 4:31 that 16th mile to get away.

And it was risky and painful! And we had ten more miles to go. But you just carry what you’re doing it for: you know, you’re carrying the [bombing] victim’s name on your bib, you’re carrying the initials on your shoulder. Every step that I made, did I think about dropping out? Absolutely. But then I’m like, no I can’t do that. And then the crowd amazingly wakes you up and makes you realize how special this is and they’re chanting “USA! USA!” or “Go Meb! Go Meb!” doing the wave, and you get emotional, you want to give your energy. I mean you just get a spark of energy and you’re like, “I’m going to do this, I’m going to do this.”

NT: That was one of the greatest races I ever watched. But back to more general strategy for a minute. On a windy day, how much are you thinking about drafting? On a sunny day, how much are you thinking about staying in the shade?

MK: When it’s hot, if you can stay in the shade, absolutely. You think about that instantly, you’re thinking about, OK there’s shade on the right. And everybody is on the right but the tangent’s on the left. So you just follow the crowd. On a windy day, it’s difficult. I try to tuck in as much as I can, but a bunch of the runners are cramped in and the chance of falling is higher. So I try to tuck in and stay back as much as I can. Then I sometimes switch to the side. People’s legs pop out and they’re not always mechanically up-and-down, up-and-down, front-and-back. I never ran and fell in a marathon but I’ve been bumped into many times, so I say, you know what, I just need to be on the side or stay far back and use them as a little windshield.

NT: I understand staying far back. You would stay on the west side if the wind is blowing from the east?

MK: Right, right.

NT: Let me ask you about your career. The last time we talked, you spoke about the ice baths, the nine-day recovery, the training cycle. Now that you’re a little ways out from retirement and you look back at the secrets that made you last so long, what else do you say?

MK: Oh, I mean the nutrition was important. When you are up to 30 years old, you can eat anything and everything. Your metabolism is still functioning really well, you get away with it. But at 33 or 35 your metabolism slows down. Instead of having no leftovers when you go to a restaurant, you cut it in half and you have half for today and half for tomorrow.

But also I think part of my longevity has been running on soft surfaces. I never ran from home, really. I'll just drive to a softer surface with dirt or grass or, you know, especially in San Diego, it’s only 2.3 miles. You can say, “Oh I’m going to run 2.3 miles to the park and run 8 miles there and two miles back.” And you get your 12-mile run in. But half of it would be on pavement, so to avoid that I always drove there. And when I'm there, I do the drills, I get to do the stretching. When I get home, I get tempted to check my phones, and see a text or a call and get distracted easily. So for me it was finish what I have to do as work when I’m at the park, versus go home and get distracted and you shower and then, you know, all of a sudden you forget to stretch. The small details can be big and lead to injury.

In San Diego, where I live, it’s a hilly place. I would have my wife drop me off, or a neighbor. It’s only 400 meters, but 400 meters when you’re running is short, but when you walk it, it takes forever.

NT: Wait, you live up a hill that’s 400 meters? And so you would have your neighbors drive you to the bottom of the hill for the start of your run?

MK: I have done it a few times, yeah!

NT: That’s awesome.

MK: I mean, I say, “Hey, are you going down the hill?” or when we drop my kids off, I say, “Hey what are you doing? Let me know when you get ready to go to work and drop me at the hill!” I’ve done that a few times. But I don’t mind running up it at the end because my body’s warm. The impact is more on your body downhill than uphill.

NT: That makes sense. Another thing that makes people slow down as they get older, or makes people quit, is that they see themselves getting a little slower from 32 to 33 or a little slower from 31 to 32 and then they say, well that’s it, now I'm getting slower, I’m done. And that didn’t happen with you. You had some moments in your thirties where it looked like you were on the way out, but then two years later you’d come back and win a marathon. Tell me about that psychological process. How were you able to keep going even when it looked to the outside world and maybe to you that age had finally caught up with you?

MK: I always say that my God-given talent is to max out. For me, I was on this earth to be a runner. But I always think, you know, because of the investment in your body, if you do the small details it will help you for longevity, yes. I ran my PR two weeks before my 39th birthday but I always believed I could run faster.

Could I have run 2:06 or 2:05 at one point in my career if everything lined up the way it did in Boston? Absolutely. But, you know, I’m not saying, “Hey I’m a 2:05 guy, let me go get that now.” There’s no way. For me it was try to be the best runner that I could ever be at the national level and the world level, and fortunately I have accomplished those. But I still enjoy running. I still love getting out. You know, the hardest part for me right now is putting my shoes on and getting out the door. And I have to do it before 11:00 usually and if I'm traveling, because if I don’t do it before that, what I eat, what I drink, has an effect on my performance. But I like to have a tea and a bagel or half a bagel or toast some bread and go. If I can do that, I’m happy.

NT: And do you still have your neighbors drive you down the hill?

MK: Now I don’t mind. If my wife’s stepping out and I know she’s going that way, I’ll do that. But I’m more casual now. If I get injured—not that I want to get injured—it’s not like I’m getting ready for the Boston Marathon or the New York City Marathon. Still, even if you’re not going for the clock time anymore as you get older, you can still enjoy being healthy.

NT: What is your advice for everybody who’s going to be out there on Monday running into maybe the rain, maybe a headwind, definitely the hills?

MK: Oh the hills, we know they’re going to be there, but mother nature has its say with the wind and the rain. Just bundle up. I used to joke around with Deena Kastor and say, dance in the rain: “You know what, it is what it is. You know, we can’t avoid the puddles or jump around, I’m going to hurt myself. Just run through it, run through it.” You know, and just have fun. Make the most of it.

It’s not easy, it’s difficult. If it was easy, everybody would be doing it. But the Boston Marathon is unique. You have to qualify to get here. So go out there and celebrate your running, celebrate your life, and have fun! I know it’s torture, but make the most of it.

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