Creatine kinase (CK) is a highly sensitive marker for muscle damage. It is well known that a wide range of exercise modalities such as high-intensity, volume training, and especially weight-bearing eccentric exercise cause the greatest rises in CK. Usually peak values are seen 24-48 hour after such exercise. Therefore a daily monitoring of CK and other exercise relevant strain markers could facilitate coaches in controlling training load. Especially, middle and long distance runners perform training camps in order to increase performance. Within these, training volume and/or intensity increases considerably compared to "normal" training procedures. Until today no clear consensus exists on which threshold of CK elevation correlates with changes in performance as well as other monitoring parameters. METHOD: 9 (2 female) highly trained middle and long distance runners from the German National Track and Field team were monitored daily during a training camp at 2100m altitude. Values for CK, resting heart rate (HR) and body weight (BW) were collected in the morning hours between 7AM and 9AM. Additionally all athletes had to rate their overall body perception (BP) and quality of sleep (QS) on a six point scale (1=very good, 6=very poor). Running speed (V3) at 3 mmol/l blood lactate was assessed before and after the training camp. All middle and long distance runners performed the same amount of training session. Each athletes performed two to three training session per day. One day with less training volume and intensity was set after 3-5 consecutive days depending on training advancement. Training intensity was controlled by heart rate, lactate values as well as CK and perceptual values. One-two days of degraded BP and QS accompanied by elevated CK resulted in a reduction of intensity or training volume. RESULT: V3 increase form 4.4±0.2 pre to 4.6±0.2. Baseline values for CK in mean were 163.1±43.8 U/L ranging from 96-241U/L. Highest values during the three weeks were found at day 17 of 20 ranging from 233 to 679 U/L. Mean CK Values for all athletes in three weeks was 346.5±146.5 U/L. The individual CK kinetics over the complete period of time revealed individuals with generally lower CK values 223 vs. individuals with considerably higher CK values (501 U/L) but same work load. Despite clear mean increase in CK body weight remained unchanged from pre to post (66.7±10.6 vs 66.6±10.3kg). Mean SQ decreased by 0.5 points towards the end of the camp. Mean BP remained unaltered. Summary: The results demonstrate low as well as high individual CK values despite equal work load. In this study mean CK values of 346.5±146.5 U/L over three weeks did not affect performance enhancement negatively. In several cases elevated CK kinetics correlated with degraded BP and QS. BW remained unaltered. The results in this study confirm the necessity to perform individual profiles of different markers in order control training over time.
© Copyright 2009 14th annual Congress of the European College of Sport Science, Oslo/Norway, June 24-27, 2009, Book of Abstracts. Published by The Norwegian School of Sport Sciences. All rights reserved.