You can find a Release of Liability Waiver here: https://www.ideafit.com/files/Release%20of%20Liability.pdf
IDEA Health & Fitness Association
I agree with Shawn. It’s always a good idea to have an attorney look over any template form that you are considering using so that your particular circumstances can be taken into account. Having a template form to go over is a great way to short-circuit the time you spend with the attorney and his or her time since their not having to draft a form from scratch though. Good luck.