The Royal Road to Health - C.A. Tyrrell

Having striven to explain in an intelligible manner the true nature and cause of disease, and to point out the inadequacy of the drug system of treatment to combat pathological conditions successfully (not from any lack of intention on the part of the drug practitioners: but from the unreliability of their methods), I shall now proceed to lay before you the system of treatment which it is proposed to substitute in its stead...

An Iron Will - Orison Swett Marden

To prosper you must improve your brain power; and nothing helps the brain more than a healthy body. The race of to-day is only to be won by those who will study to keep their bodies in such good condition that their minds are able and ready to sustain that high pressure on memory and mind, which our present fierce competition engenders. It is health rather than strength that is now wanted. Health is essentially the requirement of our time to enable us to succeed in life. In all modern occupations—from the nursery to the school, from the school to the shop or world beyond—the brain and nerve strain go on, continuous, augmenting, and intensifying.

Dare to Be Healthy, Or, The Light of Physical Regeneration - Valere Aude, Louis Dechmann