Abstract

In a cyclist, competing at national and international level, submaximal lactate concentrations were initially interpreted as improved endurance capacity. However, 2 weeks later, a test in which maximal lactate was measured showed that maximal lactate was decreased as well. Together with the complaints of deteriorating performance and subjective complaints of irritability and sleep disturbances, overtraining was diagnosed. After decreasing the training load, performance was gradually restored. This example indicates that athletes should be carefully questioned on their ability to perform their regular training programme, their motivation, possible sleeping disorders and eating problems. This case serves as a reminder to interpret lactate curves carefully and shows how important it is to obtain maximal lactate from a graded exercise test.