Nutrition at Altitude

It was great watching all the action at the Winter Olympics, but have you ever thought how the nutrition requirements might change for these athletes compared to when they come back down the mountain?! Moving to a higher altitude (moderate to high altitude = 2000–3000m, high altitude > 5000m) increases your carbohydrate and fluid requirements. This is due to several reasons:

• There is an increased use of blood glucose (carbohydrate) as fuel at rest and during exercise. This means that fatigue and low blood sugar levels will occur more quickly at the same intensity of activity at altitude compared to sea level if increased carbohydrate needs are not met.
• Air at altitude is cold and dry. Each time you breathe out in this environment, water is lost to the environment therefore increasing your fluid requirements.
• Also, short term exposure to altitude causes an increase in sodium and water losses from the body

An altitude of greater than 3500m above sea level can often cause your appetite to decrease. This can be a problem especially for people that already have high energy needs. Some people find they suffer from mountain sickness. It has been shown that a carbohydrate rich diet can help with decreasing these symptoms.
At altitude, the oxygen levels are lower, so your red blood cell production (which helps in carrying oxygen around the body) is increased. Iron is an important component of red blood cells, so it is very important to have adequate iron stores before reaching altitude to allow for the greatest production of red blood cells. Finally there is some evidence that oxidative damage from exercise is increased in sudden exposure to high altitude. It may be worthwhile taking extra anti-oxidant supplement such as vitamin C and E for first 7 – 10 days on exposure to altitude.

TOP NUTRITION TIPS AT ALTITUDE:

• Have a carbohydrate rich diet (focusing on foods such as bread, cereal, rice, pasta, fruit, potatoes etc.)
• Remember to drink plenty of fluids (preferably including sports drinks as this will help with carbohydrate as well as fluid replacement.)
• Make sure your iron levels are within the normal ranges before you move to high altitude.
• Increase your intake of high antioxidant foods.