Here is the science study I carried out during my research master degree.


Altitude training consists of living and training at some height where oxygen partial pressure is lower than sea level so the oxygen concentration that is breathed is lower. Hypoxia is a state where oxygen-deficient air is breathed (at sea level) through a device that simulates a high altitude atmosphere. The aims of these training methods are: improve sports performance, high altitude acclimation, and wellness. In the past, athletes had to travel to certain heights to achieve these benefits; nowadays there exists technology that allows these athletes to obtain the same results even at sea level. After half a century of research on how to improve sports performance on high altitudes, focusing mainly on aerobic sports, and after discovering several methods of training, a revolutionary method is born: IMIHT (Intermittent Maximal Intensity Hypoxic Training). This method intends to bond the benefits of HIIT (high intensity interval training) with benefits of high altitude training. There are only 3 research studies from 2013 that discuss this new method and the most interesting aspect is its application to team sports and intermittent & repeated bouts sports. A single-blind study was conducted with 3 groups: hypoxic (HIP) who trained under hypoxic conditions, normoxia (NOR) who trained under normal conditions and control (CON) who did not train. Several aerobic and anaerobic tests in addition to some tests that measure physiological parameters and hematological values were carried out. The training consisted of 8 IMIHT sessions (2sessions/week). A single session consisted of: 2 sets of 5 maximum intensity sprints, 20s recovery between sprints and 10m rest between sets. According to the results obtained, there is a controversy on the effect of hypoxia on HIIT programs. It has been investigated that 8 HIIT sessions produce improvements on hematological level, body composition and the tests conducted, however 8 IMIHT sessions (FiO2 = 14,5%) do not show a greater improvement evident on any of values stated. IMIHT is a very new method that may guarantee improvements and benefits on team sports and repeated bouts performance but more studies are needed to confirm its effect and applicability.


  • A learning test may improve pre-test results (the subject already knows about the test). In addition, results may be more acceptable and reliable (there will not be such large variation between pre and post-test results). Moreover, a learning test will avoid the error of a learning effect.
  • 8 sessions of HIIT may improve hematological levels of hemoglobin in untrained subjects; a greater and longer effect can be achieved when training is made under hypoxic conditions FiO2 (fraction of inspired oxygen) =14.5% (as if it was 3400 m altitude).
  • 8 sessions of IMIHT may improve hematocrit levels in untrained subjects. This effect can be prolonged after finishing the training period (minimum 2 extra weeks).
  • 8 sessions of HIIT may positively affect fat loss and body mass, thus an improvement on body composition is achieved. These findings are not as great under hypoxic conditions.
  • HIIT may improve intermittent and repeated bouts performance in untrained subjects and this effect may be prolonged after 2 weeks of having completed the training period. While under hypoxic conditions the improvement is not as great and the effect does not last very long after training is finished.
  • HIIT may improve mean power in first sprints (repeated sprints test) while IMIHT may improve sprints’ peak power.
  • Due to the controversy shown, more studies about IMIHT are needed to prove its effectiveness on sport performance.

Research Master Degree. Dissertation 2013/14. University of Extremadura. “Effects of a Intermittent Maximal Intensity Hypoxic Training program (IMIHT) on Intermittent & Repeated bouts”.


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