The winter blizzard that rolled through the front range here in Colorado this past weekend was a great reminder of why we love to live here: it’s easy to get out and play, but not so easy to choose what to wear. And aside from the 300-plus days of sunshine and abundant access to parks and recreation, both serious endurance athletes and fitness-minded folks flock here for our relative proximity to the troposphere. For the altitude.
Higher elevations can not only provide fun, challenging terrain to play and train on, but the lesser availability of oxygen causes our bodies to adapt in ways that are beneficial for athletic performance as well as our general health.
But there are several misconceptions about how and why you should train at altitude.
Exercising at altitude does not burn more calories.
One exercise bout at altitude will not cause long-term adaptations like increased red blood cell production.
And here in Denver, it’s probably not the oxygen availability that makes it seem more difficult to play a game of football or basketball, or ride your bike across town.
What makes exercise so difficult at altitude above 8000 feet or so? While the percentage of oxygen is the same everywhere on planet earth (20.93%), there’s just less air at higher altitudes. As atmospheric pressure decreases, ambient oxygen decreases as well.
Since air gets into our bodies because of differences in pressure, it’s harder to get oxygen in at higher altitudes where there’s lower air pressure. It’s like a bike tire: if your tire is at 150 psi and you open up the valve, air will shoot out; if your tire is at 50 psi, air will leak out much more slowly. The same is true of getting oxygen into our lungs.
This change in oxygen availability at altitude is very stressful for our bodies! In order to get more oxygen into our lungs, we suck in more air. In order to deliver that oxygen to our working muscles, our heart rates increase and our ventricles pump harder. Our sympathetic nervous system (the one that sympathizes with you when you need to fight or take flight) gets extra active to give us a boost. All these changes also cause us to change our fuel source from fat to carbs.
Does it sound like we’re burning more calories at altitude?
Run an 8-minute mile at sea level. To keep things equal, let’s do it on a treadmill. (Waiting…)
Now run an 8-minute mile at the top of Pikes Peak (14,115 feet). Bring your treadmill with you. It’s much harder at the top of Pikes Peak, right? Your heart rate is higher, you’re out of breath, your rating of perceived exertion is up there, but your energy requirement is still the same.
Since there’s less oxygen available at altitude, your body has to work that much harder to burn the same amount of calories.
Sure, but probably not for the reasons you may think. One training bout at altitude is just not enough exposure for your body to adapt in terms of endurance capacity. But, there are many other reasons to do it. Altitude training could improve your sprinting ability. It could help sharpen your mental game. And it will definitely make you more comfortable competing at altitude.
However, the best research says you should live high and train low. That means live at a high altitude to get the metabolic benefits, and train at a lower altitude so you can go faster and longer.
But you should still try to get out and exercise at higher altitudes when you can! Even though you may not increase your oxygen carrying capacity in the one hour you spend trail running, you can get all the other benefits: fresh air, beautiful views, challenging terrain, spiritual experiences, or whatever other awesome feeling you get when you finish a tough workout.
And those intimidating signs in every visitor’s locker room around Denver? It’s probably the dry air that makes breathing a little more difficult for someone visiting the Mile High City.