Are carbs the best fuel for high altitude running? How to prepare to run in the mountains
- Experiments on high altitude mice show that you should eat more carbs during your next high altitude running race
- Carbohydrates can help you get more ATP per unit of oxygen than using fats as fuel
Increasing your intake of carbohydrates when running at altitude could help you use more oxygen on your next high altitude mountain running race.
When running at high altitude, which is defined as anything over 2,500 metres according to medical website medicinenet.com, the lack of air pressure makes it hard for humans to extract as much oxygen from the air as we can at sea level.
A common misconception is that there is less oxygen at altitude than at sea level. In fact, the oxygen levels are basically the same. But the air pressure is less. The higher pressure at sea level makes it easier for the oxygen to pass through our vascular system. Without the pressure pushing the oxygen into our system, we take in less oxygen at altitude, making exercise harder because there’s less oxygen in our blood.
After a few days at altitude, our body acclimatises to the new conditions. We produce more red blood cells (to transport oxygen around our body) and more plasma (so the blood does not thicken too much). Utilising as much oxygen as possible is important when running, and that is especially true at altitude where oxygen intake is limited.
Carbohydrates may make oxygen use more effective at altitude, according to a 2012 paper in Current Bioldogy called “Increase in Carbohydrate Utilization in High-Altitude Andean Mice”.