Muscles require ATP (the energy currency of cells) to contract and produce movement.[1] Depending on the type, intensity, and duration of exercise, the body will make ATP primarily from one of three energy systems: the creatine-phosphate system (fastest), glycolysis, and fat oxidation (slowest). All three energy systems are always working, but some will work more than others under certain conditions. Through greater activity and training, the efficiency and effectiveness of each of these systems can be increased.
What are the different bioenergetic systems that fuel muscle?
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•Last Updated: May 16, 2025
Muscles need ATP to contract and produce movement, which is generated primarily from 3 energy systems: the creatine-phosphate system, glycolysis, and fat oxidation. The contribution of each system varies based on the type, intensity, and duration of exercise, and training can enhance their efficiency and effectiveness.