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Updated: Sep 22, 2026

Determining the Contribution of the Energy Systems During Exercise
Published on: March 20, 2012
Metabolic and hormonal reactions during training in junior oarsmen
J M Steinacker1, R Laske, W D Hetzel
1Abteilung Sport- und Leistungsmedizin, Universität Ulm, Germany.
Abstract:
This study evaluated strain reactions in young athletes (mean age: 17.6 years). Of 35 male rowers, 21 were selected by rowing ergometer tests to take part in a 26-day training camp before the World Championships in 1989. Blood samples were obtained in the morning of the day after rowing ergometer tests and on the 16th and 26th day. Cortisol (C), testosterone (T), sexual-hormone-binding globulin (SHBG), urea and creatine kinase (CK) were determined in serum and free testosterone (FT) was calculated. In the nonselected rowers C was 10% higher, FT 20% lower, and CK 42% higher compared to the selected rowers. During training, C was related to the intensity of training. It remained constant in phase 1 (12 days, increased volume of training) and increased in phase 2 (10 days, decreased volume and higher intensity). FT decreased in phase 1 and increased in phase 2. Urea showed a close relationship to training volume. CK levels decreased during the training volume. CK levels decreased during the training period as an adaptation to the training. Despite a high training load, there were no indications of overstrain reactions in these young athletes.
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