Abstract
This chapter explains the physical principles involved in the interpretation of the heat produced by muscle, i.e. the meaning of internal energy, enthalpy, entropy, free energy and efficiency. After a short description of the methods used to measure heat production on the isolated muscle specimen, this is divided into resting heat of the relaxed muscle, and initial heat developed during contraction with its components: (i) activation and maintenance heat during isometric contractions at different muscle’s lengths, (ii) shortening heat with its dependence on the applied load, (iii) the Fenn effect, i.e. the additional energy output during shortening, with its suggestive relationship between thermal and mechanical measurements, and (iv) the heat produced during stretching the contracting muscle at different velocities of lengthening. The heat produced after contraction, the relaxation heat, is shown to evolve on a much slower time scale than the initial heat with a trend that parallels that of oxygen consumption by muscle. Finally, muscular efficiency is defined in physical terms after the contraction-relaxation cycle, and distinguished from the improperly called ‘initial efficiency’ measured during shortening against different loads.
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During the fall in force taking place during relaxation it is also produced the thermoelastic heat which must not be confused with the degradation into heat of mechanical energy (Fx and elastic potential energy). The thermoelastic heat is produced (or absorbed) during the fall (or the rise) of the tension at which is subjected a body with a positive coefficient of thermal expansion. Its real nature in muscle is dubious.
References
Abbott BC, Aubert XM (1951) Changes of energy in muscle during very slow stretches. P Roy Soc Lond B Biol 139:104–117
Feng TP (1932) The effect of length on the resting metabolism of muscle. J Physiol (Lond) 74:441–454
Fenn WO (1923) A quantitative comparison between the energy liberated and the work performed by the isolated sartorius of the frog. J Physiol (Lond) 58:175–203
Fenn WO (1924) The relation between the work performed and the energy liberated in muscular contraction. J Physiol (Lond) 58:373–395
Hill AV (1931) Myothermic measurements on the frog gastrocnemius. P Roy Soc Lond B Biol 109:267–303
Hill AV (1938) The heat of shortening and the dynamic constants of muscle. P Roy Soc Lond B Biol 126:136–195
Hill DK (1940a) The time course of the oxygen consumption of stimulated frog’s muscle. J Physiol (Lond) 98:207–227
Hill DK (I940b) The time course of evolution of oxidative recovery heat of frog’s muscle. J Physiol (Lond) 98:454–459
Hill AV, Howarth JY (1959) The reversal of chemical reactions in contracting muscle during an applied stretch. P Roy Soc Lond B Biol 151:169–193
Hill AV (1964a) The effect of load on the heat of shortening of muscle. P Roy Soc Lond B Biol 159:297–318
Hill AV (l964b) The efficiency of mechanical power development during muscular shortening and its relation to load. P Roy Soc Lond B Biol 159:319–324
Hill AV (1965) Trails and trials in physiology. Edward Arnold Publ. Ltd., London
Huxley AF (1957) Muscle structure and theories of contraction. Prog Biophys Biophys Chem 7:257–318
Huxley AF (1973) A note suggesting that the cross-bridge attachment during muscle contraction may take place in two stages. P Roy Soc Lond B Biol 183:83–86
Solandt DY (1936) The effect of potassium on the excitability and resting metabolism of frog’s muscle. J Physiol (Lond) 86:162–170
Wilkie DR (1954) Facts and theories about muscle. Prog Biophys Biophys Chem 4:288–324
Wilkie DR (1960) Thermodynamics and the interpretation of biological heat measurements. Prog Biophys Biophys Chem 10:259–298
Woledge RC, Curtin NA, Homsher E (1985) Energetic aspects of muscle contraction. Academic Press, London
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Cavagna, G. (2017). Muscle Thermodynamics. In: Physiological Aspects of Legged Terrestrial Locomotion. Springer, Cham. https://doi.org/10.1007/978-3-319-49980-2_5
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DOI: https://doi.org/10.1007/978-3-319-49980-2_5
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