The four phases of heat‐production of muscle

Hill, A. V.; Hartree, W.

doi:10.1113/jphysiol.1920.sp001913

Cited by 88 publications

(22 citation statements)

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“…Thus, the contrast between these two possibilities and views is between a demand-driven system and a supply-driven system. The former, demanddriven system is consistent with the observations in fast versus slow types of muscle, with the original observations of muscle energetics by Hill in frog muscle (22,37) and with ADP control of mitochondrial oxidative phosphorylation. It is also consistent with the interpretation of the many observations that the initial reaction detectable by PNMR is breakdown of PCr and increase in Pi without detectable change in ATP.…”

Section: Organization Of the Muscle Energetics Systemsupporting

confidence: 76%

Skeletal muscle energetics with PNMR: personal views and historic perspectives

Chance

Nioka

et al. 2006

NMR in Biomedicine

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This article reviews historical and current NMR approaches to describing in vivo bioenergetics of skeletal muscles in normal and diseased populations. It draws upon the first author's more than 70 years of personal experience in enzyme kinetics and the last author's physiological approaches. The development of in vivo PNMR jointly with researchers around the world is described. It is explained how non-invasive PNMR has advanced human exercise biochemistry, physiology and pathology. Further, after a brief explanation of bioenergetics with PNMR on creatine kinase, anerobic glycolysis and mitochondrial oxidative phosphorylation, some basic and controversial subjects are focused upon, and the authors' view of the subjects are offered, with questions and answers. Some of the research has been introduced in exercise physiology. Future directions of NMR on bioenergetics, as a part of system biological approaches, are indicated.

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Section: Organization Of the Muscle Energetics Systemsupporting

confidence: 76%

Skeletal muscle energetics with PNMR: personal views and historic perspectives

Chance

Nioka

et al. 2006

NMR in Biomedicine

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“…Effect of temperature on the early stages of tension development. Earlier workers reported that exposure to low temperature delays the onset and reduces the rate of tension development in electrically stimulated frog striated muscle (Gasser & Hill, 1924;Hill, 1938Hill, , 1951 b; Hill & Hartree, 1920;Macpherson & Wilkie, 1954). In keeping with these observations, we have found that reduced environmental temperature produced pro-.…”

supporting

confidence: 78%

“…The separate contribution of each of these components to the mechanical performance of muscle has been estimated by means of quick-stretch and quick-release procedures (Gasser & Hill, 1924;Hill, 1949bHill, , 1950aHill, , c, d, 1951aHill, , 1953Jewell & Wilkie, 1958;Katz, 1939;Wilkie, 1956). Attempts to examine short-term changes in the state of the contractile elements are hampered by the relatively long interval of time required to produce controlled changes in muscle length, as well as by the aqsociated vibrations which are superimposed on tension records when muscle is abruptly stretched or suddenly allowed to shorten slightly (Hill, 1949a;Hill & Hartree, 1920). Low temperature (0-2°C) frequently has been used in an effort to slow the contractile process and thus to improve the time resolution of recorded changes in tension (Hill, 1950c(Hill, , 1951aJewell & Wilkie, 1958).…”

Section: Introductionmentioning

confidence: 99%

The time course of early changes in the rate of tension development in electrically‐stimulated frog toe muscle: effects of muscle length, temperature and twitch‐potentiators

Foulks¹,

Perry²

1966

The Journal of Physiology

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SUMMARY1. An RC circuit employing a piezo-electric crystal was used to differentiate the tension output of electrically stimulated frog toe muscle.2. The rate of tension development curves (dP/dt) usually displayed an initial step-wise increase in the rate of tension development, and often showed further discernible steps in tension acceleration. The successive stages of tension acceleration tended to be equal in duration, and approximated the length of the latent period (ca. 4 msec at room temperature). These observations suggest a synchronous turnover of the links between the myofilaments during the initial interval following stimulation, with an over-all cycle time at room temperature of about 8 msec.3. Lowering the temperature produced proportionate alterations in the duration as well as the magnitude of each successive phase of tension development, with a Qlo of approximately 2.4. Characteristic changes in the pattern of tension generation were seen with alterations in muscle length, and at lengths greater than 120 % of the standard length the irregularities in the dP/dt curves disappeared and the rate of tension development increased in linear fashion. This behaviour could be accounted for by the hypothetical S-filaments connecting the free ends of the thin actin filaments across the H-zone.5. The effects of nine twitch potentiators were studied. Only perchlorate produced prominent increases in the earliest phase of tension development and in maximum tetanus tension-properties expected with an increase in the excitation-induced release of calcium ion into the sarcoplasm (increased intensity of the 'active state').6. The time of onset of the increases in tension acceleration which were produced by twitch potentiators did not correlate with their capacity to lower the 'mechanical threshold', indicating that the amount of calcium J. C. FOULKS AND FLORENCE A. PERRY released by the action potential is not necessarily altered by a shift in the membrane potential at which calcium release occurs.7. All potentiators studied proved capable of (a) augmenting the rate of increase of tension generation (slope of dP/dt curves) during their rapid phase, as well as (b) increasing the interval during which the dP/dt curves for twitch and tetanus coincide. These effects often occurred separately.

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“…The numbers given in the above table for the heat liberated during an isometric contraction show that the course of the heat production is very different from that arrived at in the earlier investigations by Hartre e and Hill (3). In view of recent improvements in the technique the results then obtained can now be regarded as little better than a first approximation.…”

Section: W Hartreementioning

confidence: 51%

“…Each result came from a series of observations in the order: (1) isometric "long," (2) isometric "short," (3) lifting load, (4) isometric "short," (5) isometric "long," with two or three readings in each case. The results of the analysis in the twelve experiments referred to were very uniform, showing that when the load was lifted, about 15 p.c.…”

Section: W Hartreementioning

confidence: 99%

An analysis of the heat production during a contraction in which work is performed

Hartree¹

1925

The Journal of Physiology

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RECENT experiments by Fenn(l, 2) have shown that when a muscle is allowed to shorten and do work there is a further output of energy beyond that liberated in an isometric contraction. When the load was held by the muscle during contraction only, and not during relaxation, the total extra energy liberated was approximately equal to the work done, so that the energy liberated as heat was constant. If the load rested on the muscle during relaxation then still more heat was given out. It seemed desirable to consider the matter in greater detail, and to make an attempt to follow the course of the heat production during the contraction by analysing the curve of galvanometer deflection usinag the method explained elsewhere(3). By such means it was hoped to determine in which phase the extra energy associated with work was liberated. With a view to this, and to other measurements of the kind, considerable improvements have been made in the technique.The thermopile, constructed by soldering, has been improved by making it in one sheet, zig-zag fashion, holding each outer junction by thread to the supports, instead of winding the wire either round a sheet of insulator or round the arms of a U-shaped frame. If the same wire were used the new method would give only half the number of junctions per unit length, but by using finer wire (36 S.W.G. iron and constantan) the number of junctions per unit length has been maintained (35 to 40 junctions per centimetre) without making the electrical resistance excessive. Using as little insulation as possible the thermal capacity of the part of the thermopile under the muscle is now much less than before, so that its temperature changes follow more quickly those of the muscle.A further great improvement has been made by introducing a new suspension into the Paschen galvanometer used. This magnet system was constructed, with much stronger magnets of cobalt steel, by

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The four phases of heat‐production of muscle

Cited by 88 publications

References 2 publications

Skeletal muscle energetics with PNMR: personal views and historic perspectives

Skeletal muscle energetics with PNMR: personal views and historic perspectives

The time course of early changes in the rate of tension development in electrically‐stimulated frog toe muscle: effects of muscle length, temperature and twitch‐potentiators

An analysis of the heat production during a contraction in which work is performed

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