Does High Altitude Make You Sleepy? (Plus 6 Tips)

Does High Altitude Make You Sleepy

If you're on a high-altitude trek or vacation, you might be struggling with sleep and fatigue. As a company with over a decade of high-altitude experience, we'll delve into the question does high altitude make you sleepy and everything else you need to know including our best tips.

Does High Altitude Make You Sleepy?

Yes, in short high altitude can make you sleepy.

Along with being sleepy, most people can experience other similar symptoms including fatigue, difficulty breathing, and insomnia.

There's much more to understand behind why this happens, which we'll explore below, and give you our top tips to help avoid sleepiness.

Understanding Altitude Sickness

When you travel to high-altitude locations, the air naturally has less oxygen in the air. This is the kryptonite that can trigger altitude sickness with symptoms like sleepiness.

Julian Klapowitz MD states that altitude sickness can begin as low as 4,000 feet,¹ and much science shows that risk to significantly climb as you reach heights of 6,000 and 8,000 feet. Locations such as the Rocky Mountains in Colorado, the Andes in South America, and the Himalayas in Asia are famous examples of high-altitude regions with high risk of altitude sickness.

With the lower oxygen levels and increased physiological like oxidative stress, hypoxia can kick in and lead to symptoms beyond just sleepiness. These symptoms may range from fatigue and nausea to headaches and weakness.

Symptoms of altitude sickness may include:

  • sleepiness
  • fatigue
  • nausea
  • headache
  • vomiting
  • tiredness
  • weakness
  • dizziness
  • trouble sleeping
  • insomnia
  • loss of appetite
  • difficulty breathing
  • feeling ill

Be on the lookout for any of these signs as you travel to high altitudes. It's best to take precautions that can help you avoid a negative experience (mentioned below).

Can High Altitude Make You Tired?

Yes, high altitude can make you tired.

As explained in our section "Understanding Altitude Sickness", high altitude can make you tired, fatigued, sleepy, and even nauseous. This is a result of lower oxygen levels leading to physiological stress and altitude sickness.

Why Do I Feel Tired In The Mountains?

You feel tired in the mountains typically due to a combination of factors contributing to altitude sickness including oxidative stress, dehydration, and reduced oxygen levels.

One study out of Turkey highlights that exposure to hypoxia (lower oxygen in high altitudes) has negative effects on exercise capacity, sleep quality, and mental functioning.² What's most interesting is that cardiac output and resting pulse rate increases rapidly with initial high-altitude exposure,² which is most likely a factor leading to feeling tired and sleepy.

How Long Does Altitude Fatigue Last?

Based on high-altitude research, it most commonly says acclimatization can take 1-5 days.³

When it comes to fatigue, sleepiness, tiredness, and fatigue ― these are common symptoms of altitude sickness. While many factors play a role in each persons experience, by acclimating over a few days, you should see these type of symptoms start to subside.

6 Tips To Avoid High Altitude Sleepiness

Sleepiness at high altitudes can be a common challenge among other issues like weakness and dizziness.

As a company with over a decade of high altitude experience, we know with the right strategies you can minimize the impact of high elevations and better enjoy your time. We'll share our best knowledge below.

Here's 6 Tips To Avoid High Altitude Sleepiness:

1. Slowly Acclimate

Rather than rushing to your destination, take your time to slowly and gradually ascend. This allows your body to better adjust to the decreasing oxygen levels and can help minimize sleep-related issues.

For example when visitors come to Colorado, the best travel plan is to stay a few nights in Denver at 5,280 feet high before moving on to the mountains which on average can be 8,000 feet or higher.

2. Prioritize Sleep

High altitudes can disrupt your sleep patterns and sleep is key for recovery, so it's crucial to prioritize getting quality rest. Sleep is also stated to help blood flow and oxygen,⁴ which could have an effect on fatigue and sleepiness.

Shoot for 7-9 hours of sleep a night. You can further aid sleep quality by getting sunlight exposure during the day which can help support melatonin at night.

3. Limit Alcohol

Alcohol can exacerbate the negative effects of high altitude on your body, and in addition it can cause sleepiness and fatigue.⁵

While some alcoholic drinks on a mountain trip may be enticing, it's advisable to limit or completely avoid alcohol consumption until your feelings of sleepiness are gone.

4. Maximize Hydration

High altitudes, with the dry air and increased respiratory rate, has been shown to double the fluid loss found at sea level.⁶ And fatigue is one effect of dehydration noted by the National Library of Medicine.⁷

To maximize hydration, drink water regularly, even if you don't feel thirsty. Experts often recommend at least half your body weight in ounces of water per day.
TIP: Enhance your hydration by adding sea salt (naturally containing electrolytes) to your food/drink, and using Zaca's hydration supplement to support water absorption.

5. Reduce Strenuous Activity

Engaging in strenuous physical activity at high altitudes can further exhaust your body, making sleepiness and acclimatization even more challenging to combat.

Avoid overexertion and reduce strenuous activity, such as hiking and skiing, especially during the first few days at high altitude.

6. Fuel Yourself With Antioxidants

High altitudes are shown to increase oxidative stress,⁹ and increased oxidative stress has shown a potential link to fatigue.⁸ One study showed glutathione, the body's master antioxidant, to deplete by 45% in high altitudes.¹⁰

With antioxidants showing benefits in high altitudes,¹¹ take supplements containing glutathione or vitamin C to support healthy levels.

In conclusion, not only does high altitude make you sleepy, it can come with a wide range of other consequences. You can help avoid high altitude sleepiness with the right strategies ― including slowly acclimating, prioritizing quality sleep, limiting alcohol, maximizing hydration, reducing strenuous activity, and fueling yourself with antioxidants.

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1. High Altitude Illness
2. Effects of High Altitude on Sleep and Respiratory System and Theirs Adaptations
3. How Long Does It Take To Acclimate To Elevation: Plus 7 Tips
4. Sleep: The Secret Ingredient of Injury Recovery
5. Why Does Alcohol Make Me Sleepy
6. Why Do You Need to Drink a Lot of Water at a High Altitude?
7. Does Dehydration Cause Fatigue And Sleepiness? Here's What a Dietitian Says
8. A potential biomarker for fatigue: Oxidative stress and anti-oxidative activity
9. High altitude and oxidative stress
10. Effect of high altitude (7,620 m) exposure on glutathione
11. Oxidative Stress and Diseases Associated with High-Altitude Exposure
12. Why Do I Get Tired Faster in High Altitudes?