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World-class cyclists on erythropoietin.

In response to the Letter to the Editors by van Breda et al. 1 ‘Little soldiers in their cardboard cells’, we would like to acknowledge the point that the authors make regarding medical malpractice. Indeed, because of the ‘omerta’ (code of silence) in the cycling culture, the possible harm or injury caused by use of erythropoietin (EPO) in cyclists rarely sees daylight, and medical malpractice cannot be proved. Interestingly, Dr Eufemiano Fuentes was recently found guilty in Operacion Puerto of endangering public health through his doping practices. This verdict was possible partly because of the testimony by Jesus Manzano about his injury in the Tour de France of 2003, mentioned by van Breda et al. The case report in our paper 2 underlines the dangers into which these physicians put the athletes, and we hope to show the negative risk–benefit in EPO use and to encourage them to make a stand against these physicians who are practising negligence at least. 
 
Regarding the second point the authors make, it is true that a gain in maximal oxygen uptake is seen in the published studies. However, these studies are performed with trained cyclists at best, which are incomparable to world-class cyclists, as we showed in the original paper. The effects of EPO on performance parameters in elite cyclists are therefore unknown, making any further conclusions about the benefits of EPO use in this population unjustified. Additionally, it remains unclear even in trained cyclists whether EPO has an effect on submaximal exercise parameters, including power output at submaximal exercise, which is indeed the best predictor of cycling performances such as time trials 3–5. An increase of maximal oxygen uptake or maximal power output does not necessarily indicate a positive effect on submaximal parameters and therefore performance. Thus, on the basis of the evidence available in the literature, we conclude that it is not proved that EPO has a performance-enhancing effect in elite cyclists.