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
Vacuum exercise Vacuum exercise The vacuum exercise is an exercise which involves contracting some internal abdominal muscles, primarily the transverse abdominal muscle, and not as much the diaphragm. Repetitions of the exercise may be used as a form of endurance training, and light strength training. There is difficulty building strength in the muscle, as it is not easy to apply resistance training to the deeper internal muscles. The reasons for performing this exercise vary. It has been done for aesthetic purposes in bodybuilding competitions (to suck the abdomen in, making it appear less bulgy). It can be done to enhance overall core