The other factor is the increase in body temperature due to the formation of a salt layer on the skin which prevents evaporation of water from the skin. With sodium chloride baths such a rise in temperature is more prminent than with the other bath salts (e.g.magnesium). The rise in skin temperature, in turn leads to dilation of capillaries in the skin, increase in circulation, increase in consumtion of oxygen by the skin, and an increase in glandular activity. The increase in the blood flow to the skin is followed by an increase in the volume of circulating blood (from the "blood depots"), increase in the blood flow to the heart which in turn stimulates cardiac activity. This allows to "exercise" the heart muscle.