Haemoglobin, haematocrit and red blood cell indices in elite cyclists. Arethe control values for blood testing valid?

Background: In international cycling and cross-country skiing competitions, blood tests are used to unmask the performance enhancing misuse of erythro poietin. Haematocrit (cycling) and haemoglobin (cross-country skiing) limit s have been set by international sporting federations (haematocrit 50 %, ha emoglobin 18.5 g/dl). Athletes tested above these cut-off values are declar ed unfit for competition. To investigate the validity of these regulations, we studied haemoglobin, haematocrit and red blood cell indices of elite cy clists before erythropoietin became commercially available. Material and Me thods: We investigated 523 blood samples of 92 male elite cyclists (age 163 1 years) from 1978 to 1987. Haematocrit, haemoglobin and red blood cell cou nt were analysed automatically, erythrocyte indices were calculated. Result s: Haemoglobin (-0.3 +/- 1 g/dl), haematocrit (-1.2 +/- 2.8%) and red blood cell count (-0.2 +/- 0.4 x 10(6)/mm(3)) decreased significantly (p < 0.05) with increasing training workload. The erythrocyte indices showed no signi ficant change. Fifty-four blood samples (10.3 %) showed a haematocrit above 50 %, one sample presented a haemoglobin mass higher than 18.5 g/dl. Durin g periods of increased workload, less athletes tested above the haematocrit limit. Conclusion: The current haematocrit limit used in blood tests might lead to a high number of false positive tests.