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Updated: Aug 1, 2026
11:15
Determining the Contribution of the Energy Systems During Exercise
Published on: March 20, 2012
Energy system contributions in middle-distance running events
1Department of Kinesiology, University of North Texas, Denton 76203-1337, USA. dhill@unt.edu
Journal of Sports Sciences
|July 15, 1999
Summary
Middle-distance running energy demands were analyzed for male and female athletes. Anaerobic energy contribution is significant, especially in shorter races like the 400m, informing training strategies.
Area of Science:
- Exercise Physiology
- Sports Science
- Biomechanics
Background:
- Understanding energy systems is crucial for optimizing athletic performance in middle-distance running.
- Previous research has focused on elite athletes, with less data available for university-level competitors.
Purpose of the Study:
- To estimate the aerobic and anaerobic energy contributions during middle-distance running events (400m, 800m, 1500m) for male and female university athletes.
- To provide data that can assist coaches and sport scientists in developing tailored training programs.
Main Methods:
- Direct measurement of oxygen uptake (VO2) during exhaustive treadmill tests to assess aerobic contribution.
- Estimation of muscle mass using anthropometry.
- Measurement of blood lactate concentration post-race to determine anaerobic contribution via phosphocreatine stores and glycolysis.
Main Results:
- Anaerobic energy contribution was highest in the 400m race for both women (62%) and men (63%).
- As race distance increased (800m, 1500m), the anaerobic contribution decreased significantly for both sexes.
- Women's anaerobic contributions: 400m (62%), 800m (33%), 1500m (17%). Men's anaerobic contributions: 400m (63%), 800m (39%), 1500m (20%).
Conclusions:
- The anaerobic system plays a substantial role in middle-distance running, particularly in shorter events.
- These findings highlight the importance of anaerobic capacity development for middle-distance runners.
- Individualized training programs can be enhanced by considering these specific energy system contributions.
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