Effect of Factories, &c., on the Health of Artisans Employment of Children: its Consequences Effect of Confinement, Sedentary Occupation, and Constrained Relative Effect of the Deficient, the Just, or the Excessive Use of the Propensities, Sentiments, and Intellectual Faculties, ERRATA. Vol. I., page 182, line 4 from bottom, for "Prout's," read" Proust's." A TREATISE ON DIET AND REGIMEN. CHAPTER III. On Muscular Exercise.-Muscular Action.-Expenditure caused by Muscular Action.-Mechanical Effect of Muscular Action.Effect of Muscular Exercise on Nutrition.-Effect of Muscular Exercise on Respiration.-Importance of using all the Muscles.— Different Means of Muscular Exercise: Hand-Swings, DumbBells, Hindostanee Clubs, the Skipping-Rope.-Exercise Neglected in an especial degree by Women.-Deductions as to Hereditary Predisposition to Physical and Constitutional Characters, and the consequent Healthiness or otherwise of the system, as illustrating and enforcing the importance of Muscular Exercise. -Peculiar Importance of Exercise in the Years of Growth.— Dancing, as a means of Exercise.-Use all the Muscles.-Exercise in the Open Air to be preferred.—Walking.— Walking versus Carriage-Exercise.- Riding.-Sailing.- Exercise of the Voice.-Adaptation of Exercise to Mental Character, Age, Sex, Habits, and Strength.-Effect of Mind on the Degree and Effects of Muscular Exercise.-Adaptation of Exercise to different Morbid Conditions of the System.-Effects of Systematic Training, in illustration of the Importance and Influence of Muscular Exercise. Summary. MUSCULAR action forms one of the principal sources of expenditure to the animal economy. The contraction of the fibres of the muscles of the body involves a proportional waste or expenditure of certain of their organic atoms, the resolution of such atoms into new and simpler forms of composition, and (having thus ceased to be an integrant part of the living system) the necessity of their excretion from the body; the loss thus sustained being compensated by the introduction of new organisable atoms, by means of the digestive or assimilating functions. The moving apparatus of the body is only second to the function of respiration in the amount of its expenditure; and yet much of the expenditure occasioned by muscular contraction appears to subserve immediately the respiratory function, by enabling the oxygen to derive the necessary carbon, in some degree, from the detached and excrementitious atoms of the living organism. Much of the carbon required for the calorifiant wants of the system appears, however, to be derived directly from the alimentary supplies, and their instant decomposition, and the consumption of their constituent carbon; and thus, although demanding and using the larger proportion of the alimentary supplies, the function of respiration does not appear to involve by any means so large a direct expenditure of the already organised atoms of the body, as results from the action of the muscular system. It is indeed true, that, if such aliment is not afforded to the body, as is capable of furnishing carbon to the function of respiration without the complete disintegration of its atoms, and the disengagement of a large proportion of nitrogen, EXPENDITURE CAUSED BY MUSCULAR ACTION. 3 muscular action may become almost needful to the calorifiant wants of the system, and largely subservient to them. Under such circumstances, muscular action may be greatly useful to the general economy of the body, not only by the expenditure and removal of the waste and redundant matters, but by a direct ministration of the needful carbon for the respiratory wants. When the carbon required for the purposes of respiration is in a great degree supplied by the use of non-azotised articles of food, muscular action becomes less needful as regards this particular; and its principal use may be, to ensure such an expenditure of the waste of the body, as may effect the timely renewal of the organic atoms, and secure the integrity and soundness of all the organs and structures, —and, moreover, such an expenditure, as may obviate either local or general plethora, and maintain the due balance of the different bodily functions. Muscular action, involving the contraction of fibres, and consequent movement of attached or adjacent parts or structures, comprises all the apparatus of movement possessed by the animal machine, and includes the muscles of involuntary as well as those of voluntary motion. It is principally to the effects of the exercise of the voluntary muscles, that I am now about to refer. It may be useful to attempt to specify more particularly the effects on the economy of the system, of the exercise of the voluntary muscles, preliminary to a practical consideration of the various kinds of exercise, and their adaptation to the various and varying requirements and conditions of the body. |