An adventure in the hills or prairies, the point a bull elk takes his last step into bow range, all western hunts start with a dream. With that dream, a plan forms. The search for a piece of public dirt for a "do it yourself hunt" or choosing a guide is often the starting point. Follow those decisions with options for gear, food, and travel. That's all you need to plan a trip, right?
It would be easy if a trip were made of all the fun plans. But there are other things to think about, like contact devices, first aid, safety plans, and predator defense. If you're planning an adventure that will take you to soaring heights, now is the time to think of an approach to combat the effects of high altitude or acute mountain sickness (AMS).
What Happens at High Altitude?
In a two-man tent in northern Colorado, at 10,500 feet, I learned that elevation was no joke. I'd find later that week that it would take a few days to really feel myself again, but fortunately, I was prepared.
At altitude, there is less pressure. At sea level, the partial pressure of oxygen is 159 mmHg, but around 5200 feet; the pressure can be as low as 53 mmHg. Because of the change, there is less oxygen with each breath taken.
In seconds, breathing rate rises in an attempt to get more air. Recall there is less oxygen in the air, so even though breathing is faster, it's still less than your body needs. Hypoxia, a lack of oxygen, sets in and hinders sensory and motor function.
Within hours, water loss and metabolism rise. Hunger and thirst in high country add to the symptoms of AMS and can leave you feeling a lot like a used dish rag. The adjustment could take days to weeks.
At What Height Does AMS Start, and What are the Symptoms?
Often symptoms of AMS start at around 8000 feet, but some people are more sensitive. For those people, AMS may start are 5000 to 7000 feet.
Signs and Symptoms of AMS usually begin in 6 to 48 hours. Minor warnings are headaches, nausea, fatigue, dizziness, and trouble sleeping. More severe is becoming short of breath without relief when resting. Elevation can cause fluid to fill your lungs or, in extreme cases, cause swelling in your brain, so it's important to learn the warnings. The faster the ascent, the more effect the symptoms have. Because of this, a good plan is to spend one to three days between 5000 and 7000 feet to acclimate.
Is There a Way to Know Who Will Be Affected?
Unfortunately, the only true way of knowing if you are prone to AMS is when you're at a higher altitude. But a few predictors can help give you an idea!
- Medical risk. If you have known heart or lung disease, there's a chance of risk involved with altitude. Of course, that seems obvious, but you should speak with a doctor about a plan to acclimate. Most people with heart problems can run into very sticky situations around 9300 feet, so consider a plan that involves a hunt below that level.
- Medical advice. If you aren't happy with what your family doctor tells you, consider asking for a referral to a cardiac (heart) and pulmonary (lung) specialist. A lung doctor can help by doing a pulmonary function test (PFT). This test can't tell who will get AMS and who won't, but it can tell you if your lungs are healthy at your normal altitude. A heart doctor can run tests to check on heart function. A stress test is done by walking or running on a treadmill until the heart feels stressed. While the heart is under stress, your heart rhythm and blood pressure are watched closely for changes impacting how well your heart works.
- VO2 Max. This is the one most people want to hear about, but rightfully so. If you do not have any of the conditions above (or need to be sure), VO2 max is a good predictor. This test will accurately tell you how well your body uses oxygen while working out. It is similar to a stress test and can be done in an exercise lab or by one of the doctors listed above. Higher VO2 max means more efficient use of oxygen and can tell you if you've got room to improve your training plan. This test isn't required, but it could prepare you to face the obstacles caused by AMS.
Can Training Plans Help?
Yes! Of course, you can hunt and not be fit, but you'll 100% never hear anyone say they wasted their time with fitness. As for high altitude, training plans will make your hunt much more of a success. Focused training around your cardio is vital, but building muscle and strength are also important.
- HIIT training (high intensity interval training). These workouts are great for mountain training and take minimal time to perform. Some are intense enough to make you feel gassed after 15 minutes, but you should find workouts that last at least 20-30 minutes three to five times weekly.
- Low intensity training. This type of exercise includes things like running, biking, rowing, or even rucking. The main focus is cardio, and these workouts can often take more time to be effective for altitude training.
- Kettlebells. I'm not eager to jump on trends too fast, so it took a while to warm up to kettlebell workouts. But kettlebells do it all for someone looking for fast, practical training that can be done even as often as every day. They will increase strength, endurance, and cardio. You'll only need one or two sizes, they can be taken anywhere, and you can make the workout as easy or hard as you need to meet your training goals. Of course, they aren't as sexy as a bench press or dumbbell curl, but I doubt that will matter much when you've caught up to a herd bull.
What Devices Make Acclimating Faster?
As a short answer, there are none. There are some tricks for people who use a machine for sleep apnea, but they can be dangerous, even more so if a doctor isn't guiding you. Another popular thing on the market is a high altitude mask. This is a tight fitting mask that makes it harder to breathe. There is no benefit in depriving your body of oxygen. It's equal to running a car on old oil; fresh oil is the way to go if you want that engine to purr. Purposely depriving yourself of oxygen is not a good way to "teach" your body to use oxygen efficiently.
What Nutrition, Supplements, or Medications Aide in Acclimation?
Nutrition and supplementation is where we humans can get some help with AMS. We can discuss a few things that may make your experience better.
- Hydration. Being hydrated is a top priority for a mountain hunt. But surprisingly, a lot of information can lead you the wrong way. At altitude, you may only need slightly more water than usual to make up for the extra loss.
On average, a person needs about half an ounce of fluid to stay hydrated. That means if you're 160 lbs, 80 ounces (about 2.5 liters or 2500 ML) is about right, and to make up for the elevation, a 160 lbs person might want to drink at least 32 more ounces. Too much water can dilute your sodium levels and make you feel like a slug. To make it simple, you'll need at least 3 liters of water, but for hard effort, you may need 4-5 liters.
You also want to consider losses. If you've hiked in 90 degree weather and you're a person who sweats a lot, you'll need to replace that loss. The thing about sweat is that there is more than just water loss, so make sure you have electrolytes or some salty snacks!
- Sodium. Unless you have a medical condition where salt can become a problem, it can be very helpful for how well you function in altitude. Because of the increased urination and loss of sodium in altitude, your body needs it to work.
- Iron. Iron is what your body needs to make blood cells. Your blood cells have a protein called hemoglobin that contains iron. That protein attaches to oxygen and makes its way around your body. Your diet should have plenty of iron rich food before and during your hunt. Many of these foods also have good amounts of protein to help feed your muscles in high country.
- Ginko Bilboa. Ginko has some studies behind it that show its usefulness in preventing AMS. It's an antioxidant that can increase circulation by dilating your blood vessels. That can mean more oxygen to your muscles and tissues. If you have problems with bleeding, you should ask your doctor if this supplement is ok because it can increase your risk of bleeding.
- Diamox. You will have to get this prescription med from your doctor, but Diamox (FDA approved for use) can lower the chance of AMS. It can cause water, sodium, and potassium loss, so you'll need to account for that in your diet at height. This med is taken twice daily and should be started one to three days before your trip. After you reach altitude, it can be stopped after a few days. Keep in mind it can change the taste of some food and may have minor side effects. It is important to take this when directed instead of starting it when you're at your base camp.
There is plenty you can do to make your hunt an awesome experience. Educating yourself on altitude is a good way to make the challenge a zero factor when you're at full draw during a hunt of a lifetime. Don't let it stand in your way.
Author: Aaron Hepler, Exodus Black Hat Team Member