According to the two cases mentioned below, the taxpayer would need to somehow prove that these expenses were different from or in excess of what he or she would have spent for personal purposes.
A gym membership fee is an inherently personal expense. It is desirable to be physically fit regardless of one's profession. Petitioner has not offered any evidence to show that his gym expenses were different from or were in excess of what he would have spent for personal reasons. In addition, petitioner has not offered any evidence to substantiate his remaining employee business expenses [Lorenzo Battle, TC Summary Opinion 2007-27].
Taxpayer who worked for Dept. of Homeland Security and suffered from cancer was denied medical expense deductions for cost of gym membership that he didn't show was different from what he would normally spend for personal purposes [Humphrey, Kenneth, TC Memo 2013-198].
At this point, we are unaware of any court cases where a taxpayer was actually allowed to deduct the cost of a gym membership.