ERGOMETRIC AND PSYCHOLOGICAL FINDINGS DURING OVERTRAINING - A LONG-TERM FOLLOW-UP-STUDY IN ENDURANCE ATHLETES

In the present prospective longitudinal study 17 male endurance traine d athletes (cyclists and triathletes; age 23.4 +/- 6.7 years, (V) over dot O(2)max 61.2 +/- 7.5 ml.min(-1).kg(-1); means +/- SD) were invest igated both during a state of overtraining syndrome (OT: N = 15), main ly induced by an increase of exercise intensity, as well as several ti mes in a state of regular physical ability (NS: N = 62). Cycle-ergomet ric and psychological data were compared for a period of approximately 19 months. On 2 separate days, each subject performed a maximum incre mental graded exercise, two anaerobic tests (10 s and 30 s) as well as a short-endurance ''stress test'' with the intensity of 110% of the i ndividual anaerobic threshold until volitional exhaustion. The mood st ate was recorded by a psychological questionnaire including 40 basic i tems. During OT the submaximal lactate concentrations were slightly de creased. The performance of the 10 s- and 30 s-tests was unaffected. I n contrast, the duration of the ''stress test'' decreased significantl y by approximately 27% during OT compared to the individual NS. The su bmaximal oxygen uptake measured during the incremental graded exercise was slightly higher during OT as compared to NS, whereas the submaxim al and maximal respiratory exchange ratio, maximal heart rate and maxi mal lactate concentrations were decreased. At the 10 th minute of the ''stress test'', ammonia tended to be increased during OT (P = 0.048). The parameters of mood state at rest as well as the subjective rating of perceived exertion during exercise were significantly impaired dur ing OT In conclusion, the results indicate a decreased intramuscular u tilization of carbohydrates with diminished maximal anaerobic lactacid energy supply during OT. Neither the lactate-performance relationship during incremental graded exercise nor the anaerobic alactacid perfor mance showed alterations. The duration of the short-endurance ''stress test'', the maximal lactate concentration of the incremental graded e xercise as well as the altered mood profile turned out to be the most sensitive parameters for the diagnosis of OT.