MAXIMISING OLYMPIC DISTANCE TRIATHLON PERFORMANCE ...

Intermittent Hypoxic Training: A Review*Dr John Hellemans*Dr John Hellemans is a Sports Medicine Practitioner in Christchurch NewZealand. He specialises in high performance endurance sport and exerciseprescription. He is a six times New Zealand open and four times World AgeGroup Triathlon Champion.____________________Intermittent Hypoxic Training (IHT)consists of exposure to alternatingperiods of hypoxia (9 - 14% O2inhaled through a mask) andreoxygenation with atmospheric air.1, 2The method originates in Russiawhere it has been studiedextensively in the areas of aviationand clinical medicine. 1Recently it has been applied in thefield of athletic performance as analternative to altitude training. 3For the purpose of performanceenhancement IHT sessions consistof six 5 minute periods of hypoxicair (9-10%) alternated with 5 minutesof exposure to atmospheric air. A fullcourse consists of 1 or 2 sessions aday for 15 - 20 days.Adaptations to IHT do not onlyinclude improvements in oxygenuptake, transport and utilisation butalso in neuroendocrine regulationand immunity. 4,7Kolchinskaye and others have donestudies on rowers, swimmers,cyclists, kayakers, skiers, track andfield athletes and volleyball players. 3A course of IHT showedimprovements in performance, VO2max, haematological values as wellas decreased heart rates andpulmonary ventilation, compared to aplacebo group. Athletes involved inthe studies also showed a lesserincrease in arterial O2 saturationduring exercise and an improvedlactate response.Of interest is that volleyball playersshowed a significant improvement inthe Vertical Jump test following IHT.One study showed a significantincrease in resistance to highphysical training loads measured byproducts related to activation of lipidperoxidation. 5It is acknowledged that theadaptation process to IHT is notnecessarily exactly the same asthose obtained during altitudehypoxia and that additional adaptiveprocesses might be responsible forsome of the more pronouncedeffects of IHT. 6,7Meerson describes the followingadvantages of IHT in comparisonwith continuous hypoxic exposure. 7:1. Avoidance of chronic stressassociated with continuousexposure to hypoxic air.2. Controlof the dose.3. The absence of thedisadaptation syndrome whichathletes experience when returningto sea level following altitudetraining.4. Increased activities ofantioxidant enzymes in the brain,liver, heart and other organs. (In62