Does Altitude Training Increase Red Blood Cells?

The Science Behind Altitude Adaptation

Altitude training has long been used by endurance athletes, mountaineers, and professional sports teams to improve performance. One of the most commonly discussed benefits is the potential for increased red blood cell production, which can improve oxygen transport throughout the body.

But does altitude training actually increase red blood cells? The short answer is yes — under the right conditions.

Understanding how altitude affects the body helps explain why simulated altitude systems are widely used in endurance sport and expedition preparation.

Why Red Blood Cells Matter for Performance

Red blood cells are responsible for carrying oxygen from the lungs to working muscles.

The more efficiently oxygen can be delivered throughout the body, the better muscles can perform during endurance exercise.

Higher red blood cell levels can improve:

• aerobic endurance
  
  

• oxygen delivery to muscles
  
  

• fatigue resistance
  
  

• high-altitude tolerance.
  
  

Because of this, many endurance athletes look for training strategies that support improved oxygen transport.

How Altitude Affects the Body

At higher elevations, the air contains less available oxygen compared with sea level.

When the body is exposed to lower oxygen levels, it responds by activating several physiological adaptations designed to improve oxygen delivery.

One of the key responses is the release of a hormone called erythropoietin (EPO).

EPO stimulates the body to produce additional red blood cells, which increases the blood’s capacity to carry oxygen.

This adaptation is one reason altitude training has been used for decades by endurance athletes.

How Long Does It Take to Increase Red Blood Cells?

The body does not increase red blood cell production instantly.

Altitude exposure typically needs to occur over several weeks to stimulate measurable changes.

Many altitude training programs involve:

• 3–6 weeks of altitude exposure
  
  

• 6–10 hours of exposure per day
  
  

• gradual increases in simulated altitude.
  
  

Athletes often use altitude sleeping systems that allow them to sleep in reduced-oxygen environments overnight while training normally during the day.

This strategy is known as sleep high, train low.

What Is Sleep High Train Low?

The sleep high train low method involves:

• sleeping at simulated altitude
  
  

• training at normal oxygen levels.
  
  

This approach allows athletes to gain altitude adaptations while maintaining high training intensity.

Because training quality can decrease when exercising at altitude, sleeping at altitude while training at sea level allows athletes to benefit from both environments.

Altitude simulation systems make this approach possible without travelling to mountain training camps.

Do Altitude Training Tents Work?

Altitude tents and hypoxic systems simulate high-altitude environments by reducing the oxygen concentration in the air.

This creates conditions similar to those found at elevation.

When used consistently over several weeks, altitude exposure may stimulate adaptations associated with endurance performance and altitude acclimatisation.

Altitude sleeping systems are now widely used by:

• endurance cyclists
  
  

• triathletes
  
  

• marathon runners
  
  

• mountaineers
  
  

• ultra endurance athletes.
  
  

Altitude Training vs Altitude Masks

Altitude masks are often marketed as altitude training tools, but they function very differently from true altitude simulation systems.

Altitude masks

Altitude masks increase breathing resistance but do not reduce oxygen concentration.

Altitude systems

Altitude generators and sleeping systems reduce the oxygen level in the air, creating a genuine hypoxic environment.

This allows athletes to experience physiological responses similar to those seen at altitude.

Who Uses Altitude Training?

Altitude training has been used across endurance sports for decades.

Common users include:

• professional cyclists
  
  

• marathon runners
  
  

• triathletes
  
  

• ultra endurance athletes
  
  

• mountaineers preparing for high-altitude expeditions.
  
  

Many Olympic training programs and sports science laboratories also study altitude adaptation.

Altitude Training at Home

Modern altitude systems allow athletes to simulate altitude environments at home.

These systems typically include:

• altitude generators
  
  

• altitude sleeping tents
  
  

• hypoxic training systems.
  
  

By integrating altitude exposure into everyday training environments, athletes can implement altitude training strategies without travelling to high elevation.

RedCel Altitude Training Systems

RedCel develops altitude systems designed for athletes, explorers, and performance-focused individuals seeking to integrate altitude exposure into their training.

Our altitude systems support training approaches such as:

• sleep high train low
  
  

• altitude acclimatisation
  
  

• endurance performance preparation.
  
  

Conclusion

Altitude training can stimulate physiological adaptations related to oxygen transport and endurance performance.

When used consistently over structured training blocks, altitude exposure may support the body’s ability to adapt to lower oxygen environments.

For athletes seeking to incorporate altitude training into their routines, modern altitude simulation systems allow these strategies to be implemented at home.

Explore RedCel Altitude Systems

Discover how RedCel altitude training systems can support endurance preparation and altitude adaptation.

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