More athletes may have to get used to the sight of a doctor with a needle demanding blood from their bodies before a race following experiments at the recent World Nordic Skiing Championships.

Blood was taken from some of the cross country racers at the championships in Norway just before races and tested for high levels of haemoglobin, to see whether they were cheating by blood doping.

International Olympic Committee (IOC) doping expert Patrick Schamasch said yesterday that he was following the developments. It is possible that international skiing officials could ask for similar tests to be used for the first time at next year's Nagano Winter Olympics.

High haemoglobin levels boost endurance by enabling the blood to transport more oxygen to working muscles.