Exercisign at Altitude

By Fitness/Wellness Contributor, Josh Cantor

Traveling to high altitudes is always something interesting, especially for a South Florida boy like myself. Unfortunately, there are multiple issues to consider that accompany a change in altitude stemming from a decreased concentration of oxygen in the air. This obviously affects a person’s ability to be active, but can bring about serious symptoms such as altitude sickness (nausea, lethargy, feeling uncoordinated) and in severe cases, can even lead to fainting. I wanted to shed some light on how this happens and provide some tips on how to avoid issues when exercising at altitude on your next trip.

It is commonly understood that your body needs oxygen for muscles, organs, and all bodily tissues to live and function.  At sea level, oxygen molecules comprise 21% of the air.  If you are accustomed to this concentration of oxygen, or something close to it, then you will most definitely feel the difference as you travel upwards.  At 5,000 meters (16,000 feet) of altitude, oxygen makes up only 12% of the air. This is a significant drop, and at this level, your breathing rate will increase, you will feel sluggish and will probably experience a dry throat.  To help offset this decrease in oxygen concentration, your body begins a cascade of events in order to regain homeostasis, i.e. “normalcy”.

Altitude will alter your metabolism.  The lack of available oxygen forces your body to work harder.  The diaphragm contracts at a faster pace to increase breathing rate.  This will make the muscles controlling inspiration and expiration, i.e. breathing, (mostly rib and thoracic postural muscles) work harder as well.  These changes push your body to a more acidic state where it will utilize predominantly carbohydrates for energy rather than fat or protein.  Upon arrival to a higher altitude,  your metabolic rate can alter by up to 20%! The problem is that most people don’t realize the significance of these changes.

When I traveled to Ecuador a few years ago, I was subjected to this truth.  I took a car service from Cuenca to Quito, which lies about 2,800 meters (9, 186 ft) above sea level and is one of the highest capital cities in the world. By the time I arrived in Quito, I had a pounding headache, lost my appetite and energy altogether (I almost lost my lunch because of the way our driver was taking those hairpin turns too).  I went to dinner that evening and didn’t even touch my food.  It took me a few hours to stabilize my condition and regain my appetite.  The next day, I was still feeling pretty out of it, but I managed to push through.

The general rule of thumb is to wait a few days upon arrival at a higher altitude before engaging in strenuous physical activity. Most people travel to these areas in hopes of either mountain biking, mountain climbing, or hiking, but immediate physical activity can be dangerous. High altitude regions are usually cooler and people often forget that your body still sweats when its cold out. So consider picking up a some active shorts if necessary.

The International Mountain Medicine society actually recognizes three distinct altitude regions. High altitude is defined between 1,500 and 3,500 meters (4,900-11,500 ft), very high altitude falls between 3,500- 5,500 meters  (11,500- 18,000 ft.),  and extreme altitude is anything above 5,500 meters (18,000 ft).  Obviously, the recommendations for acclimation are dependent upon which altitude region you are traveling from and what altitude region you are traveling to. General acclimation takes about 10 days. After this period, your body is able to work with the oxygen present in the atmosphere in a “normal” state. During this 10 day period, your body ramps up red blood cell production which transports oxygen around the body. With more red blood cells, the blood is able to transport much more oxygen to account for the decrease in oxygen concentration in the atmosphere. After the 10 day mark, your metabolism should be stabilized and you should be accustomed to activity in an elevated environment and be able to eat and exercise like normal.

It is important that this doesn’t ruin your trip.  Here are a few tips on how to compensate and get you exercising at altitude faster.

Rest early.

Be sure to allow time for your body to adapt.  This may be easiest to do during long periods of inactivity, like sleeping and relaxation. While you may be mentally ready to hit the trails, don’t overlook how important it is to listen to your body.  You may not perceive a calm and relaxing evening as important, but it is of great importance to your body.  It’s possible that you’re a marathon runner at sea level, but can’t hike 3 miles without feeling sluggish in the Rockies.

Stay well hydrated.  

This is vitally important for a number of reasons.  Your body will be losing fluids to offset the increase in demands from the body as less oxygen is available.  You will also be losing fluids to help humidify the air as it enters your body.  And finally, high altitude regions are usually cooler and people often forget that your body still sweats when its cold out.  Increasing your fluid intake will help to offset all of these problems and may even get you acclimated faster.

Increase your consumption of carbohydrates.

The quick energy that carbohydrates provide will help to offset the sluggish feeling that may arise.  Remember that the change to a more acidic pH will increase the body’s need for carbohydrates. This will also help to provide fuel for activities such as hiking or mountain climbing.  It’s not a bad idea to keep a granola bar or fruit on hand.  A “sugar crash” similar to that of a diabetic can occur and you want to prevent it at all costs.

Keep these things in mind when you head to higher ground, and you’ll be singing like Heidi from the mountaintops in no time!

Bonus Tip: After spending some time at altitude, and especially after exercising at said altitude, you’ll notice that you have much more stamina and feel much better when exercising at the altitude you live at. Think about a Kenyan runner!