Runner’s High (with guest speaker Emily Nist)

A discussion about the biomechanics behind running at altitude, including the effects of altitude on the body, how to combat it, and how to utilize it to enhance running performance.


Caroline: Hi, Emily, thank you so much for joining us today. It’s great to have you.

Emily: Yeah, of course. Thanks for having me. I’m super excited to talk about our subject today.

Caroline: Yeah. So we have a really cool topic to talk about today, which has to do with running at altitude, which you have a lot of experience doing being a D one college athlete running and cross country and track in college, and also being from Idaho and living at altitude. So to start off, can you tell us a little bit about your experience with running and how you got into it? And how you would train?

Emily: You? Yeah, absolutely. So I started running cross country track when I was in middle school, probably around seventh grade, I wasn’t really good at any other sports. But for some reason, I could run pretty well. But it wasn’t until my freshman year of high school that I got competitive with it, and started to focus more on my trainings each season, throughout high school just because I was still growing. Yeah, looking back, I didn’t feel like my training was too intense. And we took a pretty reasonable approach to it to make sure that I wouldn’t burn out during my high school years and could still have fun with running and competing. And it was towards the end of high school, when I was starting to get recruited to do one programs that I started to take it more seriously.

Caroline: That’s awesome. Thank you for that introduction. So before we get more into the podcast, today, I will just give some background context on some of the effects that altitude can have on our bodies. So when we go up to a higher elevation, it feels can feel a little bit harder to breathe in the air might seem thinner. In a certain regard, this can be true, the higher up, you go in that atmosphere, the more the pressure decreases, and so therefore, the levels of the oxygen, levels of oxygen in the air also decrease. So this forces our bodies, specifically our hearts to work a lot harder. And it has to be more frequently in order to pump blood out at a faster rate and get oxygen to ourselves quicker.

Emily: Wow, that’s super interesting. What kind of effects would it have just like regularly, like while you’re just living it at altitude? 

Caroline: Yeah, so even if you’re living up there, or you go up there for a short trip, you can certainly notice the effects. I have personally experienced them. I went up to altitude, several, probably like 10 years ago, and I experienced altitude sickness, I got really sick. I was dehydrated, which made matters worse, I ended up passing out I’m never passed out. But I got sick. And I passed out and threw up and yeah, so definitely can have some pretty strong effects. If you’re not careful.

Emily: Oh, no, that does not sound good. One thing I have learned living at high altitude as that really the best way to adjust is by hydrating well, not only while you’re up there, but like as you go up to altitude as well.

Caroline: I very much agree. So what was your hardest part about your training?

Emily: I think the hardest part about training was just kind of the maintaining the balance of training really hard to obviously improve performance, but also resting to give your body and to, you know, have rest and give your body the ability to recover. There was a lot of professional runners I looked up to while I was in high school and college and honestly still continue to follow. And one thing that they did was they would go to altitude to have training books to get the best value of aerobic fitness. And so when I was at Syracuse, the women’s cross country team, playing a month long altitude training trip to Lake Tahoe one summer to help us prepare for that upcoming cross country season. And during this trip, we did a handful workouts but honestly our just main focus was getting in mileage at the altitude. And there were parts of that Tahoe area that were, you know, around 8000 and even 9000 feet, which honestly ended up being a really ideal altitude level for our training benefits. And it definitely took our teams, multiple runs over the first few days to get adjusted. We all thought the end run runners, we were in pretty good shape. But I think the first run we were wheezing and gasping for air. But then the other thing that we did not anticipate was kind of the fatigue we had feel. By the end of the trip we you know, felt like we’ve trained hard and we’ve reaped the benefits of getting in the mileage at higher altitude.

Caroline: Wow, yeah, that sounds really fun to go to Lake Tahoe but also very difficult, same time. So one of the main changes that happens to the body with altitude is tachycardia. So as I mentioned, your heart rate will increase and the cardiac output will also increase. But so because your body isn’t getting as much blood, as I said, it’s trying to compensate as much oxygen from blood, it’s trying to compensate by pumping out more blood. So over time, your body does acclimate. And the ratio of blood pumping out to the speed of your heart rate kind of levels out and you end up getting a cardiac output that would be about the same level is when you’re at sea level. So at first, it does feel very taxing on the body. But there have been studies that explain how, after a long period of time, this does not end up being a detrimental effect to the physical or running performance. So luckily, this does work to help runners and acclimation, our bodies really work and get better at that. So you run marathons now, correct?

Emily: I do. Yes.

Caroline: So how’s it been going from Idaho, which where you were born raised, which is at a higher elevation to Syracuse, which is lower, and now you’re living in Colorado, so you’re back to hire again?

Emily: Yeah, the, you know, as I said, I love marathons. I think they’re really fun, the race is super challenging. But honestly, the training segments that lead into a marathon are really challenging, but really rewarding. And so, you know, I hadn’t spending time in Syracuse, which was honestly as good as sea level, kind of, I think took out, you know, that kind of, like you said, your body adjusts to being an altitude, so I lost that adjustment. So upon moving to Colorado, I felt like it definitely took me almost two months to kind of get adjusted to the altitude again. And, you know, once I did get adjusted, I do think it led to being a great training perk. So being here in Colorado, I could, was able to travel to even higher altitudes than what Denver was located out to get a value for some of my long runs and prep for the marathon. So I could drive to Neverland, which is 7500 feet where Denver’s that, you know, 5000 feet. And so when I ran the Boston Marathon this past October, I did I definitely feel the difference and the benefit of coming down to sea level for that race.

Caroline: Awesome. Thank you. So living in Denver, I’m sure you’re gonna be able to go on some really cool runs. And so when you go on quick trips up to the mountains go on runs or any hikes up there? Do you notice any change in your breathing or your leg muscle if the your legs get fatigued quicker? And just any overall running performance?

Emily: Yes, so can as I just mentioned, I do love to venture out to some higher oil or higher elevation towns to explore trails for my rounds. Last summer actually did a trail race in Aspen, where the elevation of the race ranged from 8000 feet and the highest point was over 10,000 feet.

Caroline: Wow, that is extremely high up.

Emily: Yeah, I actually never done a race at altitude before. And even like, this is like super high altitude. So even with months of training beforehand, racing, you know, racing is a much diff grant type of speed type of intensity than just going out for a run. So that was a big challenge for me, and I felt the altitude, but most of my lungs, but also in my legs, they definitely fatigued quicker that was in our running the same that’s in Denver.

Caroline: Yeah, that sounds really fun to go up to altitude. But I don’t know if I could personally run a long race up at altitude. So some pretty other interesting effects that the altitude has on us besides our cardiac output and breathing is the effect it has on our muscles, and specifically our legs. So while you’re running, obviously, your legs are going to be the muscles that are affected the most and that feel the most tired. And so the legs kind of have a little bit of a harder time getting blood flow to them. So it’s pretty common that we feel a lot of muscle fatigue since they aren’t getting as much oxygen as they used to. So there are studies that have looked at this and the effects where runners go to altitude for several weeks, two months. And they compare it to when they’re at sea level and the results show that the blood flow to the legs. The muscles in the legs was about a liter less than while sea level so there was a significant difference there.

Emily: Yeah, I definitely feel the difference in my leg. So kind of, I guess, for example, if I run, you know, seven foot, three per mile pace and Denver, it doesn’t really fatigue my legs that much, it’s a very comfortable piece for me. But at altitude, my legs definitely feel like bricks from lactic acid at 730 pace, much quicker than they would here in Denver.

Caroline: So is there anything that you tried to do to combat this muscle fatigue and failure?

Emily: The biggest thing, kind of like we had mentioned earlier in our conversation is just staying hydrated, but it’s not, you know, staying hydrated, just before or after it’s before, during and after runs. It’s a longer more intense run than I use noon, electronic tablets to get a little bit more value from my hydration. You know, for the leg purpose, you can use a foam roller to kind of almost just like roll out that lactic acid and ice baths are another tool that I use on. You know, another thing as far as recovery is making sure to get a lot of sleep than I after a big run in altitude.

Caroline: Awesome, that all seems like very key steps to help with that. muscle fatigue. So moving on to the next subject, future research on this topic. So you have an experience using an altitude right, tell me a little bit more about that.

Emily: Yeah, so in high school, I was given a unique opportunity of using an out your tech during one of my cross country seasons. And the time was similar in structure to a camping tent, but it had this machine that would kind of generate air and give the same amount of oxygen as if you’re at 10,000 feet, the tank was customizable. So I had this setting where you could go you Oh, you’re at 10,000 feet or to 14,000 feet. So I was able to kind of put the setting that would almost best serve the needs of reaping the benefits of being at altitude. I would sleep in the tent every night. And it was helpful for recovery to sleep at that, at that kind of altitude or imitated altitude level because it would build up my red blood cell storage and, and really help with training.

Caroline: So when you were using the altitude tent, did you notice? Like what was it like going to bed? Like? Did you feel like it was hard to sleep at night like you felt a difference breathing? Or what were the changes you felt using that?

Emily: It definitely felt — it took a little bit of time to get used to I felt like I was kind of restless. At the first probably two weeks that I that I used it just because like yeah, you are breathing a lot thinner of air if you have this setting on, say 14,000 feet. And so you know, while you’re trying to calm down and fall asleep, they’re kind of, you know, almost taxed more by breathing a little bit harder because of the altitude level. It’s good. It took me a little bit of time, but I did eventually get obviously get used to it. And I did really feel like you know, sleep is the best way that your body recovers. So doing it altitude really did help me out.

Caroline: Yeah, also altitude tents are still pretty new. And I would say they’re not very common. I would say for probably very high level athletes and runners, they might be more common. But it’s very cool that you got to experience using one. So what they do is they really optimize the living high and training low method that has been studied, studied and research. So one of the main reasons for using this method is that it can help increase your body’s efficiency of sending oxygen, oxygen to the muscles by stimulating red blood cell production. So similar to how you said you would go on trips to Lake Tahoe during college and you’d build up that tolerance of training and altitude and acclimate and then that would make your runs and races down back at sea level. Feel almost easier in a certain regard or you just feel them go better because your body is used to the harder environment. And your body has acclimated so it’s getting like I said it’s more efficient I stimulating red blood cells so your body just feels like it endure a lot longer and more.

Emily: Yeah, exactly. And you explained it perfectly. The idea a red blood cells are huge for aerobic fitness and our muscles and building muscles and recovery and the best way to build up those red blood cells is throughout sleep and so that’s why the tent is just such a special train O’Toole.

Caroline: Awesome. Thank you so much for joining us. Emily, do you have any last remarks for us any tips?

Emily: Um, I mean, training altitude is obviously super bad of a show. But I think my favorite part about it is that takes you to beautiful trails in the mountains. And it’s, you know, trying to do on a trail run makes you feel like you’re not running it, which distracts you from the breathing hard because of the altitude, so it’s well worth it.

Caroline: Awesome. Yeah, one. One thing that I think would be cool to get a little bit more research done would be on taking supplemental oxygen before exercising to altitude. And I wonder if I know they’re for a different type of demographic than runners more for people, the older generation, and if they are on oxygen tubing or anything like that, or anyone who can get sick from altitude quickly, they have those cans of supplemental oxygen. And so I wonder if any runners use that or if there’s any studies on that. That could be a future topic that we could look at.

Emily: Yeah, that would be really interesting. And definitely research that I would find fascinating.

Caroline: All righty, that is all for today. Thank you so much, Emily.

Emily: Yeah, thanks for having me. This. This subject is awesome.

Caroline: All right. Well, I hope you all enjoyed and hopefully learn something. See you next time.

Transcribed by


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Mazzeo, R.S. “Physiological Responses to Exercise at Altitude.” Sports Med. Vol 38. 2008. Pg 1-8.

Robert Naeije.  “Physiological Adaptation of the Cardiovascular System to High Altitude,Progress in Cardiovascular Diseases”. Vol 52. #6. 2010. Pg 456-466.

Erica A.   Hinckson  and  Will G.   Hopkins, “Changes in running endurance performance following intermittent altitude exposure simulated with tents.” European Journal of Sport Science. Vol 5. #1. Pg 15-24. 2005. Pub. Routledge.

Featured image “mountain” by Kiwi Tom is licensed under CC BY 2.0.