For a health club, the major operating costs are personnel to run child care and group classes and sell memberships. In 2008, Rick Berks, founder of Planet Fitness, settled on a new model he called Youfit. His plan: Eliminate aerobics and spinning, child care and sales, along with swimming pools and ball courts, and instead offer what most people actually use — cardio equipment and weight machines. By slimming down his costs, he was able to slim down membership fees, eliminating an upfront fee and contracts. He charges $10 per month for access to a single club or — Youfit’s most popular membership — $19.99 to access all clubs, including the ability to bring guests and get perks such as half-off drinks. “People want value for their money,” Berks says. Berks’ Pompano Beach-based company is on its way to having more than 50 clubs nationally by year-end. He says the company is profitable but wouldn’t disclose revenue or profit numbers.