The old concept of altitude training does improve endurance performance. Or more to the point, living at altitude and training at sea level does! Back in 1997 and 1998 two studies (Levine and Stray-Gunderson, 1997 and Chapman et al 1998) showed that this concept of training at sea level and living at altitude produced an increase in endurance performance of 1.4%!
Their participants lived at an altitude greater then 2500m for 4 weeks trained at 1300m and on returning to sea level achieved this quite impressive improvement in a time trial performance. The study also tested another group of participants who lived and trained at altitude again above 2500m and this group showed no significant improvement in performance.
They concluded that this increase in performance was attributed to two necessary changes to the body. These were an increase in red blood cell count that increases the ability of the body to supply the working muscles with oxygen. They found that this occurred in both groups but it was only the group that trained at the lower altitude that gained in speed in the sea level trial. Secondly the athletes who trained at altitude train their muscles at the same speed as those at the lower altitude. This caused the motor recruitment of the train high group to become slower at their race pace and slowing the propulsion of the subjects.
The group that trained low and lived high was that they received a welcome boost to their VO2max (the maximum amount of oxygen utilised by the body at maximal intensity) by having a reduced cardiac output for a sub-maximal effort at sea-level. This meant that they were more efficient at utilising the oxygen in the blood. It was also found that no real change occurred to their muscles so the ‘improvement’ must have some from some other change in their bodies. Chapman et al (1998) put this improvement down to an increase in erythropoietin (EPO) (the hormone that controls the amount of red blood cells produced) produced by their kidneys and this resulted in the improvement in performance and VO2max.
The authors suggested that this effect would take place when three criteria are fulfilled,
1. Live above 2500m for a suitable amount of time (e.g. 4 weeks)
2. Have adequate stores of iron to allow for the increased production of red blood cells.
3. To be able to train at the same muscle contraction speed associated with their sport, at sea-level or around 1300m.
References
Chapman, R.F., Stray-Gundersen, J., Levine B.D. (1998) Individual variation in responses to altitude training. J. Applied Physiology. 85:1448-1456. Cited in Lore of Running. (2003) Noakes. Human Kinetics, Leeds. Fourth Edition
Levine, J. Stray-Gundersen, J., (1997) ‘Living high-training low’ Effects of moderate altitude acclimatization with low altitude training on performance. J. Applied Physiology 83: 102-112. Cited in Lore of Running. (2003) Noakes. Human Kinetics, Leeds. Fourth Edition