German biochemist Otto Fritz Meyerhof (1884-1951) shared the Nobel Prize in Physiology or Medicine for his discovery of the fixed relationship between oxygen consumption and the metabolism of lactic acid in muscle and for for establishing the cyclic character of energy transformations in the living cell.
In 1909 he graduated as a doctor of medicine at Heidelberg. Later he worked in the laboratory of the medical clinic at Heidelberg.
In 1906-1907 (Sir) Walter Morley Fletcher and (Sir) Frederick Gowland Hopkins proved that, when muscle contracts under anaerobic conditions, lactic acid accumulates in it and that when oxygen is supplied the lactic acid disappears. The chemical reactions involved or the way in which they release energy for contraction were not known until Meyerhof entered the field at the end of World War I. But in the physical field A. V. Hill since about 1910 had been investigating the heat produced in muscle on contraction. He showed that the heat was proportional to the work performed; he also demonstrated that about half the heat appeared during the anaerobic contraction phase, while the other half was evolved during the aerobic recovery phase.
In 1920, Meyerhof showed that in anaerobic conditions, the lactic acid was derived from glycogen in the muscle and that the amount of lactic acid formed was proportional to the tension produced in the muscle. And, in the recovery stage only between one-fifth and one-quarter of the lactic acid was oxidized, and the energy of this reaction was used to reconvert to glycogen the remainder of the lactic acid.
Meyerhof proved that in anaerobic fermentation, for the release of a given amount of energy, more carbohydrate is used up than is the case if the carbohydrate is oxidized (the Pasteur-Meyerhof effect). He introduced the term “glycolysis” for the anaerobic degradation of glycogen to lactic acid, and he demonstrated the cyclic character of energy transformations in the living cell. For these researches Meyerhof shared with Hill the 1922 Nobel Prize for Physiology or Medicine.