Hill and Meyerholf received the Nobel Prize for mapping how muscular tissues generate warmth and switch glycogen into lactic acid |Picture used for representational function solely
| Picture Credit score: Soumyadip Sinha
Archibald V. Hill and Otto Meyerhof studied how muscular tissues use chemical vitality to contract and get better. Hill measured the warmth produced by working muscular tissues, whereas Meyerhof traced the connection between oxygen consumption and lactic acid metabolism. Their work earned them the 1922 Nobel Prize in Physiology or Drugs.
The prize was divided equally. Hill was recognised “for his discovery regarding the manufacturing of warmth within the muscle”, whereas Meyerhof was recognised “for his discovery of the mounted relationship between the consumption of oxygen and the metabolism of lactic acid within the muscle”. The prize was awarded for 1922 however offered in 1923 as a result of the Nobel Committee had initially determined that no 1922 nomination met the required standards.
Measuring muscle warmth
Hill approached muscle physiology as an issue in physics in addition to biology. Working largely with frog muscular tissues, he developed exact strategies for measuring the very small quantities of warmth generated throughout contraction.
The adjustments had been tiny. In a single experiment described in his Nobel lecture, a single contraction of a frog’s sartorius muscle at 20°C raised its temperature by not more than about 0.003°C. Hill used delicate devices and punctiliously managed contractions to separate warmth produced throughout exercise from warmth generated throughout restoration.
His measurements confirmed that warmth manufacturing didn’t finish when the muscle stopped contracting. A second section, which Hill known as restoration warmth, continued after contraction and relied on oxygen. When oxygen was eliminated, this restoration warmth was abolished.
This was vital as a result of it confirmed that the vitality adjustments related to muscle contraction and restoration occurred in distinct phases quite than as one steady course of.
Meyerhof traces the chemistry
Meyerhof investigated the chemical facet of the identical drawback. In experiments on frog muscle, he measured warmth manufacturing and oxygen consumption and adopted the conversion of carbohydrates into lactic acid.
He confirmed that in muscle exercise, lactic acid was fashioned from carbohydrate. Throughout restoration, among the lactic acid was oxidised whereas the rest was transformed again into carbohydrate. These observations helped set up the connection between oxygen use and lactic acid metabolism for which he obtained the Nobel Prize.
Meyerhof’s work went additional. Between 1918 and 1922, he supplied proof that glycogen was transformed into lactic acid when oxygen was absent. He additionally discovered that solely a fraction of the lactic acid produced throughout anaerobic muscle exercise was subsequently oxidised within the presence of oxygen, with a lot of the rest being reconverted to glycogen.
Two sides of muscle metabolism
Hill and Meyerhof had been investigating completely different elements of the identical physiological drawback. Hill measured the bodily penalties of muscle exercise — warmth, work and vitality expenditure. Meyerhof examined the related chemical reactions.
Their findings related the bodily and chemical sides of muscle metabolism. Hill’s measurements of restoration warmth may very well be defined by Meyerhof’s observations on lactic acid and oxygen consumption. Hill himself acknowledged that Meyerhof’s biochemical work helped full the image that bodily measurements alone couldn’t present.
A hyperlink to fashionable metabolism
Meyerhof’s analysis contributed to the rising understanding of glycolysis, the pathway by way of which cells break down glucose and different sugars to acquire vitality.
His observations additionally led to what turned generally known as the Pasteur-Meyerhof impact: respiration can suppress the breakdown of carbohydrates by way of glycolysis. His work supplied early proof that vitality transformations in residing cells may contain cyclical processes, an concept that turned vital within the improvement of contemporary middleman metabolism.
The terminology and biochemical fashions have since modified considerably. Muscle metabolism is now understood to contain a number of pathways and vitality carriers, together with ATP, quite than being defined merely by way of lactic acid.
An attention-grabbing a part of Meyerhof’s scientific profession is that he didn’t stay dedicated to each interpretation that emerged from his early work.
The invention of creatine phosphate in 1926 led him to query the concept that lactic acid itself was immediately accountable for supplying the vitality required for muscle contraction. He subsequently revised elements of the mannequin that had grow to be related along with his work.
The Nobel recognition
Hill and Meyerhof delivered their Nobel lectures on December 12, 1923. Hill’s lecture was titled The Mechanism of Muscular Contraction, whereas Meyerhof’s was titled Vitality Conversions in Muscle.
Their work established quantitative approaches to finding out muscle metabolism, bringing collectively measurements of warmth, mechanical work, oxygen consumption and chemical adjustments.
Greater than a century later, the small print of muscle vitality metabolism are understood in far better molecular element. However Hill’s measurements of warmth and vitality and Meyerhof’s work on oxygen, glycogen and lactic acid had been vital steps in establishing muscle as a system whose mechanical exercise may very well be linked to measurable chemical and thermodynamic processes.
Printed – September 13, 2026 07:04 pm IST