The IRS treats general health, fitness, and appearance costs as personal, even when they arguably help you perform at work. So a typical freelancer cannot deduct a gym membership simply because being healthy makes them more productive.
There are narrow, fact-specific exceptions. A personal trainer or fitness instructor who must pay for gym access to actually deliver sessions to clients may have a legitimate business cost, but that is different from a general personal membership. These situations are specific and worth confirming with a tax professional.
If you are a fitness professional, track the costs that are genuinely required to deliver your service separately from your personal fitness spending, since only the former has any chance of being deductible.
A useful gut check: would you keep paying for this whether or not you were self-employed? For a gym membership, the answer for most people is yes, which is a sign it is really a personal expense. Equipment or certifications a trainer needs specifically to run their business are a different story and belong in their own records.

