Let exercise alternate with rest.
Moderate exercise is indispensable; exercise till the mind feels delight in reposing from the fatigue.
It is exercise alone that supports the spirits, and keeps the mind in vigor.
A bear, however hard he tries, grows tubby without exercise.
The word aerobics came about when the gym instructors got together and said, "If we’re going to charge $10 an hour, we can’t call it jumping up and down."
Any workout which does not involve a certain minimum of danger or responsibility does not improve the body — it just wears it out.
My idea of exercise is a good brisk sit.