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 Effects of Exercise and Improved Circulation.—1. The skin is made fresh, pink, and smooth from the flushing of the capillaries; it is purified by the perspiration and the renewal of cells. 2. If the fat is too great in amount, it is burned up; if it is too small in amount, the better nourishment brought by the blood increases it. 3. The muscles are better fed (see Fig. 48) and grow firm, strong, and large. 4. The skeleton is held in proper position by the stronger muscles, and deformity is prevented. 5. The brain. The pure, fresh blood, loaded with oxygen from expanded lungs, flushes every capillary of the brain, clears the mind, and doubles or trebles its power to work. 6. The lungs are expanded by deep breathing if the exercise be rapid and vigorous. A slow stroll or saunter is not of value. 7. The circulation. Every contracting muscle aids the heart in its work. The deep breathing moves stagnant lymph. 8. The stomach. Exercise burns up the food and increases the appetite. 9. General effects. Exercise promotes good humor, decreases loafing, cigarette smoking, gossiping, and other vices.

The effect of tobacco on the heart, if cigarettes or cigars are used, is sometimes to cause attacks of irregular beating; the heart flutters faintly for a while, then palpitates strongly, then flutters again. This condition is called tobacco heart, or trotting heart.

Effect of Alcohol upon the Circulation.—After a person has taken an alcoholic drink his face and skin are likely to become flushed, and perhaps his heart beats faster. Most investigators have found that the alcohol itself does not directly increase or strengthen the action of the heart. Hence it is probably wrong to call alcohol a heart stimulant. The flushing of the skin is believed to be due to the relaxing effect of alcohol. It relaxes, it paralyzes, the