Abstract

To induce an overtraining syndrome in 8 experienced middle- and long-distance runners training volume was increased from an average 85.9 km (wk 1) to 115.1 km (wk 2) and 143.1 km (wk 3) to 174.6 km/wk (wk 4). The influence of this training on cardiovascular, metabolic and hormonal parameters was examined with special respect to plasma and urinary catecholamines. Graded treadmill testing was performed on the days 0, 14 and 28. Stagnation in endurance performance capacity and decrease in maximum working capacity were observed in 6 and a stagnation in 2 of the 8 sportsmen. The athletes could neither improve nor could they even approximately reach their personal records during the subsequent competitive season. Glucose, lactate, ammonia, glycerol, free fatty acids, albumin, LDL, VLDL cholesterol, hemoglobin level (transient), leukocytes and heart rate decreased significantly. Urea, creatinine, uric acid, GOT, GPT, gamma-GT and serum electrolytes (except phosphate and Ca) remained constant, CPK was elevated. Noradrenaline plasma levels increased at the same submaximum workload during treadmill ergometry. Basal, nocturnal urinary catecholamine excretion fell to 28-30, the 24-h cortisol excretion to 70 of baseline values. The decrease in urinary noradrenaline excretion and the complaint index were correlated. We conclude, the increase in exercise-induced noradrenaline plasma levels during treadmill ergometry combined with a 70 in urinary catecholamin excretion may be of diagnostic value in short-term overtraining. Verf.-Referat (gekuerzt)