Glycolysis involved in glycolysis. The burning sensation in muscles during hard exercise can be attributed to the release of hydrogen ions during the shift to glucose fermentation from glucose oxidation to carbon dioxide and water, when aerobic metabolism can no longer keep pace with the energy demands of the muscles. These hydrogen ions form a part of lactic acid. The body falls back on this less efficient but faster method of producing ATP under low oxygen conditions. This is thought to have been the primary means of energy production in earlier organisms before oxygen reached high concentrations in the atmosphere between
Neural control of limb stiffness inherent stiffness. These variable stiffness acutators are able to control their inherent stiffness in multiple ways. Some vary their stiffness much like humans do, by varying the force contribution of antagonistic mechanical muscles. Other actuators are able to adjust their stiffness by taking advantage of the properties of deformable elements housed within the actuators. Neural control of limb stiffness As humans move through their environment, they must change the stiffness of their joints in order to effectively interact with their surroundings. Stiffness is the degree to a which an object resists deformation when subjected to a known force. This idea