Students who with limited time and means are struggling to gain an education should realize that time spent in physical exercise is not lost. Those who continually pore over their books will find, after a time, that the mind has lost its freshness. Those who give proper attention to physical development will make greater advancement in literary lines than they would if they devoted their entire time to study. TEd 126.3
Physical inaction lessens not only mental but moral power. The brain nerves that connect with the whole system are the medium through which Heaven communicates with humans, and affects the inmost life. Whatever hinders the circulation of the electric current in the nervous system, thus weakening the vital powers and lessening mental susceptibility, makes it more difficult to arouse the moral nature. TEd 126.4
Again, excessive study, by increasing the flow of blood to the brain, creates morbid excitability that tends to lessen the power of self-control. Thus the door is opened to impurity. The misuse or nonuse of the physical powers is largely responsible for the tide of corruption that is overspreading the world. “Pride, fullness of bread, and abundance of idleness” are as deadly foes to human progress in this generation as when they led to the destruction of Sodom. TEd 126.5
Teachers should understand these things, and should instruct their pupils in these lines. Teach the students that right living depends on right thinking, and that physical activity is essential to purity of thought. TEd 127.1