Abstract

The purpose of this study was to examine the effects of short-duration exercise during different periods of a years training cycle on the activity of plasma creatine kinase, lactate dehydrogenase, and Gamma-glutamyltranspeptidase in cyclists and kayakers. A group of cyclists performed a Monark bicycle ergometer exercise until exhaustion, with the initial rate of 60 rpm being gradually increased by 10 rpm to reach 110 rpm. Every 4 min there was a 10 s maximum acceleration. A group of kayakers performed 16 min exercise on an EK-1 kayak ergometer, with 1 min interval after each 4 min exercise bout. The first exercise was performed with approx. 50 Vo2 max, followed by 80, 85, and 100 Vo2 max. The results have shown a slight increase of plasma enzyme activity, significant (p<0.05) only in the kayakers studied in March, as compared with the resting values. Analysis of mean resting CK activity values in both groups and of LDH in kayakers revealed significant (p<0.05) differences, depending on the period of the years training cycle. The incidence of increased CK and LDH activity above the physiological standard was found to decrease with the duration of training. The results suggest that analysis of resting plasma CK and LDH activity may be useful in evaluation of the athletes trained condition and adaptation; however, further studies are required to confirm this observation. Verf.-Referat