Letter to the Editor

Dear Editor

The recently published paper by Van Thuyne and Delbeke [[3]] presents relevant data about caffeine use after its removal from the WADA doping list. Because some were afraid that the misuse of caffeine might increase after its removal from the doping list, the urinary concentrations have been monitored since. The data presented by Van Thuyne and Delbeke [[3]] show that the misuse did not increase, although in some sport disciplines such as cycling some misuse of caffeine was still found. The authors conclude that if unfair play should be prevented it might be reconsidered to add caffeine to the list again with a urinary threshold level of 12 µg/ml. However, it should be emphasized that research has shown that caffeine has performance enhancing properties up to approximately 5 mg/kg [[1], [2]], above which no additional effect on performance was found [[2]]. However, when dosages up to 5 mg/kg are taken the urine levels generally stay below 12 µg/ml [[2]]. So, there is no scientific basis to support the statement that re-establishing a threshold of 12 µg/ml would avoid unfair competition. The misuse found in some sports may be attributed to lack of knowledge and education which appears to be supported by the facts in several doping cases. An important, but too often underscored aspect of the fight against doping is education of athletes and people around the athlete. The recommendation to add caffeine to the doping list again ignores the reasons why it was removed some years ago. Proper education in those sports where caffeine is still abused may be a more effective approach.

References

• 1 Graham T. Caffeine and exercise: metabolism, endurance and performance.  Sports Med. 2001;  31 785-807
• 2 Kovacs E MR, Stegen J HCH, Brouns F. Effect of caffeinated drinks on substrate metabolism, caffeine excretion and performance.  J Appl Physiol. 1998;  85 709-715
• 3 Pasman W J, van Baak M A, Jeukendrup A E, De Haan A. The effect of different dosages of caffeine on endurance performance time.  Int J Sports Med. 1995;  16 225-230
• 4 Van Thuyne W, Delbeke F T. Distribution of caffeine levels in urine in different sports in relation to doping control before and after the removal of caffeine from the WADA doping list.  Int J Sports Med. 2006;  27 745-750