[Testimonies for the Church 2:525-527 (1870).]
The chief if not the only reason why many become invalids is that the blood does not circulate freely, and the changes in the vital fluid, which are necessary to life and health, do not take place. They have not given their bodies exercise nor their lungs food, which is pure, fresh air; therefore it is impossible for the blood to be vitalized, and it pursues its course sluggishly through the system. The more we exercise, the better will be the circulation of the blood. CH 173.1
More people die for want of exercise than through overfatigue; very many more rust out than wear out. Those who accustom themselves to proper exercise in the open air, will generally have a good and vigorous circulation. We are more dependent upon the air we breathe than upon the food we eat. Men and women, young and old, who desire health, and who would enjoy active life should remember that they cannot have these without a good circulation. Whatever their business and inclinations, they should make up their minds to exercise in the open air as much as they can. They should feel it a religious duty to overcome the conditions of health which have kept them confined indoors, deprived of exercise in the open air. CH 173.2
Some invalids become willful in the matter and refuse to be convinced of the great importance of daily outdoor exercise, whereby they may obtain a supply of pure air. For fear of taking cold they persist, from year to year, in having their own way and living in an atmosphere almost destitute of vitality. It is impossible for this class to have a healthy circulation. The entire system suffers for want of exercise and pure air. The skin becomes debilitated and more sensitive to any change in the atmosphere. Additional clothing is put on, and the heat of the room increased. The next day they require a little more heat and a little more clothing in order to feel perfectly warm; and thus they humor every changing feeling until they have but little vitality to endure any cold. CH 173.3
Some may inquire, “What shall we do? Would you have us remain cold?” If you add clothing, let it be but little, and exercise, if possible, to regain the heat you need. If you positively cannot engage in active exercise, warm yourselves by the fire; but as soon as you are warm, lay off your extra clothing and remove from the fire. If those who can, would engage in some active employment to take the mind from themselves, they would generally forget that they were chilly, and would not receive harm. You should lower the temperature of your room as soon as you have regained your natural warmth. For invalids who have feeble lungs, nothing can be worse than an overheated atmosphere. CH 174.1