A gym (from Ancient Greek gymnásion, "place to be naked") is nominally a facility in which humans voluntarily load their own skeletal muscle to provoke hypertrophy and increased strength via adaptive overcompensation.
This mechanism is named progressive overload, a rare gift-offering from biology. Sometimes, however, users' consistency is gated by akrasia. Additionally, many users are wrong and not effectively optimizing for the claimed desired outcome. This is common to many human endeavours.
The real purpose of gyms is to convert people's New Year's Resolutions and expensive city-centre real estate into idle subscriptions.
— gollark