"To make a muscle grow, you must force it to go beyond its capabilities. The most potent way to apply that force is to train to failure. Training to failure means...the muscles are forced to grow stronger and bigger"

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... what is really inspiriting and ennobling in the doctrine of freewill, is the conviction that we have real power over the formation of our own character; that our will, by influencing some of our circumstances, can modify our future habits or capabilities of willing.

— John Stuart Mill