1. Introduction
2. What is blood doping?
3. How does it work?
4. Respiratory physiology
5. The physiology of endurance sports
6. Ventilation during endurance sports
7. Cardiac output during endurance sports
8. Aerobic metabolism during endurance sports
9. Conclusion - blood doping kills
10. References

In order to understand the mechanism of EPO as an ergogenic aid it is necessary to understand the limiting factors for maximum oxygen uptake during endurance performance. Maximal oxygen uptake (VO2max) was first defined by Hill et al (1922) who stated:

1. There is an upper limit to oxygen uptake
2. There are interindividual differences in VO2Max
3. A high VO2 Max is prerequisite in endurance performance
4. VO2max is limited by the cardiorespiratory system to transport O2 to the muscles.

Bassett and Howley (2000) described four limiting factors of VO2Max. They were:

1. Pulmonary diffusing capacity
2. Cardiac output
3. Oxygen carrying capacity
4. Skeletal muscle limitations

The first three can be described as central limitations and the fourth peripheral. It is the third of these which is affected by EPO and haemoglobin levels. The use of recombinant EPO has been shown to increase VO2max (Ekblom and Berglund 1991).

Respiratory physiology >