Altitude masks work by providing the same conditions as a place that is high altitude on sea level. Altitude training and respiratory muscle training has been reported to improve performance in those that use them. Regardless of what type of workout you are doing wearing a mask or not you will see improvement in aerobic capacity (VO2max), endurance performance, and lung function. However, those who use an altitude mask have shown improvement in ventilatory threshold (the amount of work the muscles can maintain without fatigue), power output from ventilatory threshold, respiratory compensation threshold, and power output at respiratory compensation threshold.
When the ventilatory threshold is surpassed, the muscles don’t receive the necessary amount of oxygen and that is when we start to become fatigued. When the body is exposed to hypoxic conditions (lower oxygen) it stimulates the kidneys to create erythropoietin (EPO), which increases red blood cell production. In turn this gives your hard working muscles a better chance to receive the oxygen they need to reduce fatigue.
On top of the endurance metrics, altitude training has been shown to improve deep breathing and increase ventilatory efficiency throughout exercise when not wearing the mask. The mask works by covering your nose and mouth. You then adjust the valves to increase the resistance, making it more difficult to breathe.
A few side effects of altitude training include: lightheadedness, dizziness, fatigue, discomfort, anxiety, lower alertness and focus, hyperventilating, and fainting. REMEMBER that you are reducing the amount of oxygen you can breathe and these are normal side effects for a reduction in oxygen. Take it slow and listen to your body. If you have high blood pressure or cardiovascular disease it is NOT recommended that you use this type of mask.
Sources:
Porcari JP, Probst L, Forrester K, et al. Effect of Wearing the Elevation Training Mask on Aerobic Capacity, Lung Function, and Hematological Variables. J Sports Sci Med. 2016;15(2):379-386. Published 2016 May 23.
https://sites.udel.edu/coe-engex/2020/02/25/elevation-masks-for-endurance-training-stamina-or-scam/
