EXS101 Energy Systems Demo
Energy Systems: Working Together
Choose an activity and observe how all three energy systems work together to regenerate ATP (adenosine triphosphate).
Explore Activity Examples
Select an example, then play or view its endpoint. Settings illustrate continuous activity, not individual physiological predictions.
Slow Walking
Qualitative teaching model: bar lengths are not measured energy percentages, ATP production rates, or values to add together. All three systems contribute; their roles overlap rather than switching on and off.
View research evidence and references
Published findings below are whole-bout estimates under specific study conditions. They are not values assigned to the activities above.
30-second maximal cycling [2]
Smith and Hill studied six men completing modified Wingate tests. Estimated whole-bout contributions were phosphagen 28%, glycolytic 56%, and aerobic 16%. Phosphagen power peaked in the first 5 seconds, glycolytic power at 10–15 seconds, and aerobic power in the final 5 seconds. These are study findings, not universal crossover times.
Simulated running events [3]
Spencer and Gastin studied 20 highly trained athletes. Estimated whole-bout aerobic contributions were 29% for 200 m, 43% for 400 m, 66% for 800 m, and 84% for 1500 m. A pathway's contribution at one moment differs from its accumulated contribution across the whole activity.
- Baker, McCormick & Robergs (2010). Interaction among Skeletal Muscle Metabolic Energy Systems during Intense Exercise. Review supporting overlap, rapid onset responses, and capacity limits.
- Smith & Hill (1991). Contribution of energy systems during a Wingate power test. DOI: 10.1136/bjsm.25.4.196.
- Spencer & Gastin (2001). Energy system contribution during 200- to 1500-m running in highly trained athletes. DOI: 10.1097/00005768-200101000-00024.