@Triste Joven,
Most of it is true... A used tool never rusts is the saying, but it will wear out, and often wear you out in the process... We know that it is not stagnation that causes a loss of purity, and stagnation is often used in the process of purifying water of sediments, and with calcium carbonate, a lot of chemicals, oders and flavors can be made to precipitate out...
None the less; I believe the conclusion is ultimately correct... Minds, if they be more than a moral form, need exercise as much as the body, and exercise for the body also is good exercise for the mind... I never hang onto a stair master or a treadmill... I often read while walking or walking backwards... Strength is nothing without balance and coordination, and if I cannot leave the gym more knowledgable as well as more fit, I feel my workout has been something of a failure...