Gymnesia 

When you have not been to the gym for an extended period of time due to laziness or any other poor excuse.

Donnie: Where you been homey, I haven't seen you in ages?
Greg : All this partying is really taking its toll. I have severe gymnesia!

Gymnesia by Gregsands August 22, 2012

Gymnesia 

A habitual or compulsive involvement in physical exercise in a gym or fitness centre that leads to the detriment of other aspects of the individual's day to day life.

I haven't seen Billy for a while. Where's he got to?
That guy's got a bad case of Gymnesia!

Gymnesia by BijomaruMogami September 1, 2017

gymnasia

when used in a husky voice, it can be used as the term to want to have sex in a gym

"I really want some gymnasia"
"Why, yes i will have sex with you in a gym!"

gymnasia by james-in-a-box May 15, 2008

gamnesia 

the loss of memory of events that occurred during the relationship after the relationship has ended.

Did I say that, I don't remember doing that with you. I never said or did such a thing. (but I could have gamnesia).

gamnesia by tydwell July 25, 2006