Human beings are the only mammals that really stand up straight. Of course, some of the big apes make a pretense of doing so, but certainly none of them has achieved the human ideal - heels together, head up, shoulders back, chest out, and belly sucked in. Many persons in attempting this posture remind one of Dr. Johnson's description of preaching women and dogs walking on their hind legs: "It is not well done. The wonder is that it can be done at all."
This erect attitude has made it difficult for the circulation in man's legs. Hence dilated veins, stagnation of the blood within, and the tissues round about swollen with fluid; changes in the arteries, and many resulting troubles in the tissues. The muscles and tendons have a tough job with all the weight of the body to handle instead of the half which the quadrupeds have on each pair of legs. Then higher up, the balancing puts great strain on the bones, muscles, and tendons.
Inside the abdomen, gravity and the erect position combine to make more trouble for us. Any or all of the abdominal organs may sag down. This is known as visceroptosis, or dropping of the guts. A few swallows of barium and an X-ray examination of a thin, narrow person may sometimes show a most remarkable displacement downward of the stomach and intestines. This leads to one of the few arguments I know of for accumulating fat. As people plump up, they often overcome their visceroptosis.
There is one trouble in which the value of the horizontal rather than the vertical position has been often demonstrated, as is well known to many physicians. That is diarrhea. Many diarrhea mixtures have been used; nearly all of them, I think, have some opium in them which quiets the bowels. They also frequently contain some chalk-like material which, I believe, is supposed to coat the bowels. Abstinence from food combined with the horizontal position for a prolonged period is a simpler treatment but effective.
Now we have Dr. Richard H. Overholt telling us in the Journal of the American Medical Association that "septic bronchiectasis (pus in the small air passages of the lungs. Ed.) is another penalty imposed on modern man for his evolutionary assumption of an erect position." The infected secretions do not travel uphill freely from the lower part of the lung. Standing the patient practically on his head is a well recognized treatment.
We have now arrived at the head and my friend the rhinologist (he treats your nose) continues the sad tale by informing me that man is peculiarly subject to trouble in his sinuses because they do not drain well as he stands erect. We have not much data as to relative positions above the nose, but how often does one see a quadruped with a bald head?
We must retain a reasonableness in all things; not go to extremes as we so often do. But a moderate amount of lounging is good for most of us. (People with sick hearts and difficulty in breathing may be exceptions.) More time in the horizontal position is a common prescription. It may well be used before the onset of illness.