Planet Fitness Inc. (NYSE:PLNT) has become something of a stock market juggernaut, up 370% since its 2016 IPO. The national chain of no-frills gyms and fitness centers continues to impress with steady growth and increasing profitability. The differentiation of the brand is an industry-leading low monthly membership fee from $10 which is made possible as the locations typically only feature workout equipment to maximize space with limited amenities. Planet Fitness now has 14 million members across 1,859 locations. The core business of selling gym members may seem simple, but a deep dive here