Anaerobic exercise

[2] The biochemistry of anaerobic exercise involves a process called glycolysis, in which glucose is converted to adenosine triphosphate (ATP), the primary source of energy for cellular reactions.

An example is high-intensity interval training, an exercise strategy that is performed under anaerobic conditions at intensities that reach an excess of 90% of the maximum heart rate.

[7] Some methods estimate the anaerobic component of an exercise by determining the maximum accumulated oxygen deficit or measuring the lactic acid formation in muscle mass.

The benefits of adding anaerobic exercise include improving cardiovascular endurance as well as build and maintaining muscle strength and losing weight.

Anaerobic glycolysis exclusively uses glucose (and glycogen) as a fuel in the absence of oxygen, or more specifically, when ATP is needed at rates that exceed those provided by aerobic metabolism.

The consequence of such rapid glucose breakdown is the formation of lactic acid (or more appropriately, its conjugate base lactate at biological pH levels).

Strength training belongs to anaerobic exercise.
Fox and Haskell formula
As muscles contract, Calcium ions are released from the sarcoplasmic reticulum by release channels. These channels close and calcium pumps open to relax muscles. After extended exercise, the release channels can begin to leak and cause muscle fatigue.