This (Gym-bike_and_thread-mill mod) is just an optional script , you may not need it... Made it as a quick edit just in case..
I save not cars in the garage, (I just go in the game, spawn a car and head out) Same way i almost never save the game, i just go in the game, hang out for a while then i just exit.. Which simple means that i would not have noticed this... I'm not sure when it started, if it is when i was testing the no hunger mod before the initial release or whenever but i realised that for some reason the player could no longer loose fat while working out on the gym machines (like the thread mill and stuff, so i made this as an alternative instead of relying on the scm for everything... You may not need it, but i just include it just in case and it can also be used for other purposes i guess.