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Updated: Mar 7, 2026

Determining the Contribution of the Energy Systems During Exercise
Published on: March 20, 2012
Energy systems efficiency influences the results of 2,000 m race simulation among elite rowers
Stefan Adrian Martin1, Valeriu Tomescu2
1Community Nutrition and Food Hygiene Department, University of Medicine and Pharmacy Tîrgu Mureş, Romania; Romania Rowing Federation, Bucharest, Romania.
Hypothesis:
Energy efficiency within an elite group of athletes will ensure metabolic adaptation during training.
Objectives:
To identify energy system efficiency and contribution according to exercise intensity, and performance obtained during a 2,000 m race simulation in an elite group of rowers.
Method:
An observational cross-sectional study was conducted in February 2016 in Bucharest, Romania, on a group of 16 elite rowers. Measurements were performed through Cosmed Quark CPET equipment, and Concept 2 ergometer, by conducting a VO2max test over a standard rowing distance of 2,000 m. The analyzed parameters during the test were: HR (bpm), Rf (b/min), VE (l/min), VO2 (ml/min), VCO2 (ml/min), VT (l), O2exp (ml), CO2exp (ml), RER, PaCO2 (mmHg), PaO2 (mmHg), Kcal/min, FAT (g), CHO (g), from which we determined the ventilatory thresholds, and the energy resource used during the specific 2,000 m rowing distance (ATP, ATP+CP, muscle glycogen).
Results:
We performed an association between HR (180.2±4.80 b/min), and carbohydrate consumption during the sustained effort (41.55±3.99 g) towards determining the energy systems involved: ATP (3.49±1.55%), ATP+CP (18.06±2.99%), muscle glycogen (77.9±3.39%). As a result, completion time (366.3±10.25 s) was significantly correlated with both Rf (p=0.0024), and VO2 (p=0.0166) being also pointed out that ≥5 l VO2 value is associated with an effort time of ≤360 s. (p=0.040, RR=3.50, CI95%=1.02 to 11.96). Thus, the average activation time among muscle ATP (12.81±5.70 s), ATP+CP (66.04±10.17 s, and muscle glycogen (295±9.5 s) are interrelated, and significantly correlated with respiratory parameters.
Conclusions:
Decreased total activity time was associated with accessing primary energy source in less time, during effort, improving the body energy power. Its effectiveness was recorded by early carbohydrates access, as a primary energy source, during specific activity performed up to 366 seconds.
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