Page:Popular Science Monthly Volume 48.djvu/700

628 in gain of chest girth, forty-two per cent; and in gain of lung capacity, seventy-five per cent. It is probable that alcohol and other poisons have similar effects.

Exercise of the skeletal muscles is contraindicated in hæmorrhage, fever, inflammation, certain toxæmias, and serious injuries. Pain is an uncertain indication; if it result from inflammation or local injury, exercise is contraindicated, otherwise not necessarily. In acute local inflammation exercise is very injurious, since it increases the local congestion. Severe or sudden exertion should not be permitted in cases of aneurism, atheromatous arteries, cardiac vegetations or extreme cardiac weakness, but systematic training may be beneficial in the latter condition. Severe exertion should also be avoided soon after eating and in states of great physical and mental fatigue. Nothing will break down the system more quickly than the combination of mental worry or strain with physical prostration, though gentle exercises are often of value in resting the brain by bringing new centers into play, and thus effecting a better distribution of cerebral activity. It is futile to add to the burden of individuals already overworked, and the proper remedy in such cases is the reduction or proper proportioning of their total work, better hygiene, and provision for adequate periods of rest, repose, and recreation, which are the efficient antidotes for the toxic effects of excessive exercise. Well-chosen exercise may often be made to minister to mental poise, and thus to restful effects. It has been pointed out that the individual patient usually needs not exercise or rest exclusively, but exercise and rest in the proper proportions and in the proper order. The beneficial effects of treatment may often be enhanced by placing the two in sharp contrast. Exercise produces a better impression on a background of rest, and rest on a background of exercise; and particular attention should be paid to securing variety of action by contrasting one set of exercises with others involving different groups of muscles, or the same groups in a different manner. The level road may be the harder to travel in the long run. Neither its specific effect in any named disease, still less the piling up of enormous masses of muscle, is the therapeutic object of exercise, but the production of definite local or general physiological effects. Increased muscular power is usually an incidental result, but marked remedial effects are often produced with very moderate muscular development. The too dominant idea of "gymnastics" should not make us lose sight of the vast therapeutic importance of the nervous reactions associated with muscular movements, and of the systematic culture and training of the involuntary neuromuscular apparatus, which certainly depends in large degree on the activity of the skeletal muscles, but is often best elicited by massage, passive