Defiant, Sarah says she continued with her workout regardless - but was forced out by the manager.
She wrote: "So I just got kicked out of the College of Charleston student gym for wearing this outfit. Like not allowed to work out.
"Not allowed to because of THIS OUTFIT THAT I BOUGHT SPECIFICALLY TO WORK OUT IN.
"I've worn this same outfit all day. Went to three classes and spoke personally with each of my professors today and they didn't have a problem.
"But when I walked into the gym they asked me to put on a different shirt.
"Obviously I didn't bring an extra shirt to the gym and wasn't about to wear my flannel while working out.
"So I just said mhm OK and went about my work out pretty p***** off that they even asked me to change.
"Then, when I'm in the BACK CORNER of the gym doing abs on the floor, another staff member comes up and asks me to 'put my shirt back on.'
"I said, 'I have a shirt on.' They say, 'no that's not a shirt. You have to wear a whole shirt'.
"I say 'how is this not a shirt?'
"And she [member of staff] says, 'You need full coverage. If you have a problem, we always have our boss here.'
"I laughed and said, 'Alright bring him over here if he has a problem.'
"A few minutes later while I'm doing more work outs on the floor, the 'boss' comes up.
"He says 'I'm gonna need you to put a shirt on.' Again, I tell them, 'I am wearing a shirt.
"He says, 'I need you to put on a shirt or I'm gonna have to ask you to leave.' I said, 'But I HAVE A SHIRT ON.'
"He says, 'Are you gonna put a shirt on?' And I said, 'Well if this isn't a shirt ... no. I'm not gonna put a shirt on."
"What is the issue? Why can't I work out in this outfit? Is my belly button distracting to the general 85 per cent male demographic that your gym serves?
"I'm forced to leave, WHY? Honestly I'm so floored that I just got kicked out for this. DO BETTER COLLEGE OF CHARLESTON."