We may earn a commission from links on this page.If you're building out a home gym, the first piece of equipment you need is a set of weights. While I'm a huge fan of adjustable dumbbells as a savvy cost-saving hack, there's another place to turn to save money on your home gym arsenal: Your FSA/HSA funds. Thanks to Nike's partnership with Truemed, you can now use pre-tax dollars to purchase Nike strength training equipment, potentially saving you around 30% on your fitness investments. Here's everything you need to know about turning your health savings into home gym gains.How to get a Letter of Medical Necessity (LMN)Like with using your health funds to buy wearables and fitness trackers, the secret to unlocking FSA/HSA eligibility for fitness equipment lies in obtaining a Letter of Medical Necessity (LMN). Your LMN is basically a doctor's note required to classify certain purchases as qualified medical expenses under IRS guidelines, proving that it will be used to treat a legitimate medical condition, such as obesity or a heart condition. As long as you submit an LMN to your benefits administrator, it will most likely be covered. Without this letter, the IRS considers fitness equipment a general wellness expense, making it ineligible for tax-advantaged health account funds.Traditionally, obtaining an LMN meant scheduling an appointment with your primary care physician, explaining your fitness needs, and hoping they'd write the required documentation. This process could take weeks and wasn't guaranteed to result in approval. However, third-party apps have changed the game on this front. When you're checking out your eligible purchases on Nike's site, you'll see the option to “Pay With Truemed” at checkout. From there, as Truemed explains it, you'll be asked you a few questions about your health circumstances, and you’ll be matched with a provider to determine your eligibility. This covers your fitness goals, any relevant health conditions, and how the equipment will support your wellness objectives. If you qualify, you’ll get an LMN that will allow you to use your HSA or FSA funds to complete your purchase—all without ever having to meet with your primary doctor. This typically happens within 24-48 hours, much faster than scheduling a traditional doctor's appointment.Once approved, you can complete your purchase knowing it's fully FSA/HSA eligible. If you do not qualify, you may cancel your order at any time prior to delivery.These Nike weights qualify for FSA/HSA fundsNike Strength products are eligible for HSA/FSA purchases through Truemed. The eligible equipment includes:Alpha home gym setupNike barbell and plate setNike curl bar bundleNike grind dumbbellAgain, these products qualify because they support specific health outcomes including muscle building, cardiovascular health improvement, and joint stability enhancement. The key is proving you need them for some specific health and fitness purposes, rather than general recreation.While your FSA/HSA-funds won't cover the full $2,819 cost of that home gym set-up, an average of 30% savings could be enough to justify clicking "add to card" in the first place. The bottom lineYour FSA and HSA funds were designed to support your health and wellness, and if you play your cards right, that support could extend to building the home gym with Nike strength equipment. Nike and Truemed clearly mark which products qualify for FSA/HSA funds, but you do need to prove your eligibility. Some employers' FSA administrators may scrutinize purchases more closely, but Truemed's LMN system could be your saving grace. Just remember: The most important aspect of shopping with HSA funds is record-keeping. Make sure to keep every receipt—and LMN—for every HSA purchase you make.