Triathlon Coaching I Triathlon Training

Altitude Training - Hypoxia Type 2

This type of hypoxia reaction is characterized by a longer arterial saturation time (Td (time to descend ) in the range of 90-180 seconds) and a shorter recovery period (Tr in the range of 20 - 60 sec). 

This type 2 reaction is most commonly observed in generally healthy, sedentary people. After an IHT course it is reasonable to expect an extension of the Td and further shortening of the Tr intervals.

Altitude Training - Hypoxia Type 3

The graph below typically represents the reaction of those familiar with hypoxia , for instance mountaineers or athletes who regularly hold their breath e.g. free divers.

​The time to reduce arterial oxygen saturation in these people is often more than 5 minutes and the time to recover back to 95% SpO is very short (given that they do not hold their breath artificially during either interval). 

People with this type of reaction may further improve the functional state of their oxygen processing systems as the result of an IHT course.  

Altitude Training - Hypoxia Type 1

This reaction is a quick drop in SpO2 (short Td (time to descend) in the range of 30-60 seconds) and a relatively long recovery time (Tr (time to recover) in the range of 60-190 seconds). This is determined during a hypoxic test.  Our system analyzes your reaction while you're sitting in a relaxed position while wearing a mask. The mask is issued to you during your altitude orientation session. You'll bring your mask to each altitude training session (IHT - Intermittent hypoxic training).

Td - Time to descend - This is the number of seconds of hypoxia breathing (11% oxygen)  the person tolerated until arterial oxygen saturation (SpO2) reached the baseline of SpO2  = 85% .

Tr - Time to recover - This is the number of seconds it took to recover back to a typical (for sea level) arterial saturation of 95% when the mask was taken off and ambient air was inhaled. 



Type 1 is typical for those familiar with hypoxia episodes during their training and competition. These individuals tend to have a tolerance to hypoxia, their body does not rush to turn on the mechanisms of compensation (eg. increase in ventilation and heart rate) and therefore their SpO2 tends to drop quickly . People with this type of reaction may further improve the functional state of their oxygen processing systems as the result of an IHT (intermittent hypoxic training) course.  


For non athletes not familiar with hypoxia, a quick drop in SpO2  indicates their low hypoxic hypoxia sensitivity they and reduced oxygen processing functional status. These people will most likely be susceptible to AMS (Acute Mountain Sickness) should they travel to altitude, since their hypoxic chemoreceptors do not quickly signal to their systems that their is a lack of oxygen in their blood. The good news for these people is that after an IHT course that their Td tends to increase and Tr tends to shorten, ie, they'll benefit from IHT. 

identify your Hypoxia reaction Type

Are you a type 1, 2, or 3? 

Get the edge and boost your performance.

Swimming lessons in Houston - Pasadena - Clear Lake