Voluntary muscular exercise expends the energy of both the nerve centers and the muscles. Massage stimulates vital activity in the muscles without taxing the nerve centers. The muscles are constantly active under the influence of the nervous system, even when in a state of apparent rest. This insensible activity is known as muscle tone. It is very noticeable in the abdominal muscles, the tone of which enables the muscles to act in opposition to the diaphragm, aiding in expiration.
Massage increases muscular tone by improving their nutrition.
The large blood vessels , both veins and arteries, but principally the veins, the circulation of which may be readily accelerated or impeded according as the manipulations are applied in the direction in which the, blood runs in the veins, or in the opposite direction. The large lymph channels which usually accompany the larger veins are also brought directly under the influence of massage through appropriate manipulations. The heart itself may be reached by certain special-procedures, and is greatly influenced by nearly all forms of manipulation. The large nerve trunks , which, with the terminal nerve filaments, are influenced by all forms of manipulation, but especially so by certain procedures which are particularly efficacious in producing stimulating or sedative effects. The bones, joints, and ligaments must also be mentioned as structures which are directly affected by massage.