Michael and Marc Grondahl founded Planet Fitness in Dover, New Hampshire, in 1992.
The brothers acquired and reorganized a struggling gym business, developing a low-cost membership model designed to appeal to casual exercisers as well as regular gym users. The company later became known for its “Judgement Free Zone” positioning and broad franchise expansion.
Planet Fitness clubs typically emphasize affordable access, extensive operating hours, and a less intimidating atmosphere. The brand’s “lunk alarm” and rules around certain gym behavior became recognizable parts of its marketing, although individual club amenities can vary.
Planet Fitness is not the same company as Gold’s Gym, Crunch Fitness, or LA Fitness. Those brands have different founders and histories. The 1992 founding date refers to the early Planet Fitness business in New Hampshire, before the chain developed its much larger national franchise network.