Please note that some of the links below are affiliate links and at no additional cost to you, I will earn a commission. Know that I only recommend products, tools and learning resources I've personally used and believe are genuinely helpful, not because of the small commissions I make if you decide to purchase them. Most of all, I would never advocate for buying something that you can't afford or that you're not yet ready to implement.
A fitness site can have numerous revenue streams. Create healthy eating plans and recipes and lock them away as premium content. Promote and sell a fitness training course, eBook, or a series of videos. Or advertise your own personal fitness services on your site. Topfithub is a good example of a fitness site with decent video content alongside product reviews.
In April 2008 the State of New York inserted an item in the state budget asserting sales tax jurisdiction over Amazon.com sales to residents of New York, based on the existence of affiliate links from New York–based websites to Amazon. The state asserts that even one such affiliate constitutes Amazon having a business presence in the state, and is sufficient to allow New York to tax all Amazon sales to state residents. Amazon challenged the amendment and lost at the trial level in January 2009. The case is currently making its way through the New York appeals courts.