Energy supply is the release of energy that the body needs for the individual processes. It is released by oxidation of the energy-providing substrates or nutrients. These are mainly glucose (dextrose) and fatty acids or their storage forms glycogen and triglycerides.
All forms of energy production and energy supply have only one goal: they serve the resynthesis of adenosine triphosphate (ATP) to adenosine diphosphate (ADP), which was broken down during muscle contraction, so that this is available again for energy supply. The rapid resynthesis of ADP to ATP produced during muscle work is the central problem in training energy metabolism.
Only a relatively small part of the free energy becomes usable in the form of mechanical work or osmotic work (transport), the larger part is lost as heat.
A basic distinction is made between two types of energy supply. Energy can be provided by aerobic or anaerobic metabolism.
Depending on the intensity of the load, time periods with a dominant energy supply can be determined: