I wouldn't say it atrophies. It is maintained to some extent as an unconscious part of your being alive. It can and frequently gets clogged, twisted, blocked, and otherwise obstructed due to lack of cleaning.
What does seem to atrophy is your conscious command of it. Without some amount of use, your conscious mind gets rusty on how to active your various energy skills. Fortunately, its like riding a bicycle, its much easier to remember than to learn in the first place.
[grammer edit]
Sin nada (Nothing is impossible)
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