Hypoxico - Training masks do not simulate altitude

5 May 2019

Training masks do not simulate altitude


There are many confusing training masks on the market for athletes. Some are advertised as “altitude” masks and some as “elevation” masks. But do they increase your red blood cell count like you are expecting them to?


Training at a high altitude is associated with two key environmental factors. First, a reduced partial pressure of oxygen (hypobaria). The second is a reduced concentration of oxygen (hypoxia). These factors are responsible for the physiologic changes associated with high altitude training, which can cause an increase in performance and improve endurance. Most importantly in relation to exercise performance is the hypoxic component, which cannot be mimicked by air restriction masks.


If you are researching the differences between workout masks and simulated altitude generators, it is important to keep in mind that “altitude” or “elevation” masks limit airflow in and out of your lungs. Simulated altitude generators limit or reduce the oxygen concentration or percentage being delivered to your lungs. This is why your body can go through a physiologic change even while living at sea-level.

The restriction of airflow or amount of oxygen associated with training masks is different than the hypoxic environment that is produced with a generator. Flow restriction simply limits the movement of air into the lungs, much like you would experience if you were breathing through a straw.

The restricted oxygen that is created with a training mask has the same concentration of the ambient air. This then diffuses into the bloodstream, unaffected by any changes in pressure or concentration. Meaning that any oxygen that enters the lungs diffuses into the blood which creates no physiologic change.


“Altitude” or “elevation” training masks are effective at one thing, restricting the flow of air into your lungs. There are studies that do show that flow restriction can improve inspiratory muscle training and improve exercise performance (Berry, et al. and Langer). However, in an athletic performance sense, the results are inconsequential and even more so, irrelevant.  

Air flow into the lungs is NOT a limiting factor for endurance performance, but rather it is the utilization of oxygen at the cellular level that is crucial for performance.


Training or sleeping in a hypoxic environment forces your body to respond to a reduced oxygen concentration (fewer molecules of O2 per same volume unit). Adaptation must occur in order for your body to maintain metabolic processes in this reduced O2 environment. Now you are utilizing oxygen more efficiently to help you perform at a higher level, with high intensity and more power output. Altitude Training For Endurance Athletes

Although altitude generators do not mimic the partial pressure of oxygen experienced at altitude, they do effectively mimic the hypoxia associated with high altitude. This carries more weight in promoting the physiologic and performance benefits associated with altitude training.

Created By: Kelsey Joyce, Lead Physiologist

kelsey joyce is the lead physiologist at hypoxico. kelsey is an energetic and enthusiastic physiologist with a passion for all things altitude. kelsey not only helps with identifying altitude training solutions for clients but also attends to the physiologic and research needs of hypoxico. she is an active researcher in the area of altitude physiology and carries out both chamber-based and field-based research.