If there is more dyspnea than normally should occur in the
individual patient after walking rapidly or climbing a hill or going
upstairs, or if after a period of a little excitement one finds that
he cannot breathe quite normally, or that something feels tight in
his chest, the heart needs resting. If, after one has been driving a
motor car or even sitting at rest in one which has been going at
speed or has come unpleasantly near to hitting something or to being
run into, it is noticed that the little period of cardiac
disturbance and chest tension is greater than it should be, the
heart needs resting.

If the least excitement or exertion increases the cardiac speed
abnormally, it means that for many minutes, if not actually hours
during the twenty-four, the heart is contracting too rapidly, and
this alone means muscle tire and muscle nutrition lost, even if
there is no actual defect in the cardiac muscle or in its own blood
supply. If we multiply these extra pulsations or contractions by the
number of minutes a day that this extra amount of work is done, it
will easily be demonstrable to the physician and the patient what an
amount of good a rest, however partial, each twenty-four hours will
do to this heart. Of course anything that tends to increase the
activity of the disturbance of the heart should be corrected.
Overeating, overdrinking (even water), and overuse or perhaps any
use of alcohol, tobacco, tea and coffee should all be prevented. In
fact, we come right to the discussion of the proper treatment and
management of beginning high blood pressure, of the incipiency of
arteriosclerosis, of the prevention of chronic interstitial
nephritis, and the prevention of cardiovascular-renal disease.