Simulated altitude training shows benefits
6 Jnuary 2005
Simulated altitude training shows benefits
Groundbreaking research at Lincoln University, supported by the Canterbury Medical Research Foundation, has shown that intermittent, simulated altitude training for athletes can boost the formation of immature red blood cells, important for carrying oxygen around the body.
Under the leadership of sports scientist Dr Mike Hamlin of Lincoln University’s Environment, Society and Design Division, assisted by physician Dr John Hellemans of Active Health, QEII, Christchurch, the effects of “intermittent hypoxic training” (IHT) on athletic performance were investigated.
Hypoxic refers to lack of oxygen, such as that experienced at high altitudes, and athletes in many sports have long used altitude training as a way of building up the important oxygen-carrying red cells in the blood before launching into demanding, energy-sapping events. The All Blacks use the principle when they “acclimatise” on South Africa’s High Veldt before playing at Johannesburg, around 5500 feet above sea level.
“Acclimatisation can, however, be costly and time-consuming,” says Dr Hamlin. “To spend lengthy periods fulltime at high altitude training camps ahead of an event can drain budgets and strain relationships. How much better if the same physiological effect can be achieved intermittently in simulated circumstances close to home, at a fraction of the cost.”
Simulated altitude training devices have become a popular alternative for many athletes but whether they are beneficial or not has been a matter of debate. Lincoln University’s research has come up with the first randomised double-blind, experimental data indicating that the devices may be an effective, cheaper and more convenient method of applying an altitude stimulus to endurance athletes.
The regimes the athletes were exposed to were the equivalent of oxygen levels in the air at the top of Mount Cook and even higher.
Twenty-two multi-sport endurance athletes were randomly assigned to either a placebo or hypoxic group. The subjects were similar in age, height, weight and competitive level. Over three weeks in daily 90-minute sessions on an average of five days per week, the two groups breathed through hand-held facemasks connected to a commercially available hypoxicator device.
For the IHT group the intermittent breathing was administered in a ratio of five minutes hypoxic air followed by five minutes of normal air. The oxygen concentration in the hypoxic gas was progressively reduced in the IHT group from 13% in day 1-2 to 10% by week 3.
Blood samples were taken at intervals and analysed. The subjects were also put through running time trials to determine the effect of IHT on performance.
All in all the researchers were able to conclude that the use of intermittent normobaric hypoxia in five-minute intervals for 90 minutes a day, five days a week for three weeks, was sufficient to elicit blood changes that suggest an acceleration of red cell formation. They were also able to show that this type of training was successful at increasing endurance performance.
“We have used IHT in Christchurch since 1999 with good success,” says Dr Hellemans.
“It is used not only by athletes to improve endurance but also by mountaineers and high altitude trekkers to acclimatise before arriving at altitude.
“There is now convincing evidence that IHT is an effective and convenient tool for acclimatisation, thereby reducing the chance of altitude sickness greatly.
“IHT is also effective as a complementary treatment for chronic illness, in particular heart disease, fatigue and asthma. IHT has a similar effect on bodily functions as exercise and can therefore be used for treatment and prevention.”
Dr Hamlin says that while it seems that red cell production probably plays a part in the performance enhancements found with this type of training, other mechanisms are undoubtedly at work and he and Dr Hellemans are keen to conduct further research in this field.
ENDS