Gyms Move From Machines to Fitness Playgrounds Gym members receive instruction on the two-story tower at a Life Time Fitness center in Vestavia Hills, Ala. Simple exercises with no-tech equipment (call them paleo or playground exercises, depending on how much fun they are) have long found disciples at niche gyms and in movements such as CrossFit. But in the last year and a half, major health-club chains have begun making hefting sandbags and shaking 25-pound ropes the standard, ditching the fancy weight machines that have dominated gym floors for more than 30 years. "I wouldn't say obsolete, but there is a huge downtick in traditional strength-training equipment," said David Harris, the national director of personal training for the Equinox chain. The company, based in New York, has thinned its ranks of chest press, leg press and leg extension machines to clear floor space so members can move freely. Treadmills and other cardio machines aren't going anywhere. Or as Monkey Bar Gym, which has its headquarters in Madison, Wis., states on a T-shirt: "Rage Against the Machines." In the race to make space for so-called functional fitness training - which encourages people to push, pull, squat and generally move their bodies as they might naturally - the first machines out the door are usually the ones that lock the body in place, working a single muscle. Adam Campbell, fitness director for the Men's Health brand, wrote in an e-mail that machines like the leg press strengthen muscles, but asked: "What's the real logic in sitting or laying down to train your legs?" Functional fitness is "far more bang for your buck" because it works multiple muscles simultaneously, he said, providing better overall strength and mobility, and a higher calorie burn. That makes it a faster route to today's most-wanted bodies, like those of the actors Bradley Cooper, Kellan Lutz of "Twilight" and Ryan Kwanten and Joe Manganiello of "True Blood." "Lean, athletic as opposed to highly muscular," Mr. Campbell wrote of that group, a description that could apply to some of the most-wanted bodies for women, too. Josh Bowen, until recently the quality control director for the seven-state Urban Active chain, referred to the sweeping revisions the company made last year as swapping "Arnold machines" (as in Schwarzenegger) "for AstroTurf." Mr. Bowen, who left Urban Active when it was acquired by LA Fitness, said, "Gyms are way out of the times if all they have is machines." People spend all day sitting with machines, he said. When they come into a gym, they don't want to be sat down at another one doing three sets of 12. At Life Time Fitness, the Minnesota company that has clubs in 23 states, roughly half of them have removed some machines and banished the rest to the corners to make way for what a spokeswoman referred to as "jungle gyms," essentially seven-rung ladders the width of a small room from which people can push, pull and otherwise suspend themselves. This month, the chain's 106th club opened in Alabama with a two-story steel structure big enough for some 40 members to run up stairs, climb rope walls and hoist themselves up poles. "It looks like a prison guard tower," Jason Stella, Life Time's national training developer, said with pride. (Mr. Stella isn't sure how many clubs will get a replica. "We won't get planning permission everywhere," he said.) The 160-branch Town Sports International, which includes New York Sports Clubs, has removed up to eight machines a club - biceps, triceps, leg extensions and leg curls are the first to go - and replaced them with 800 square feet of artificial turf. Some potential members may still judge gyms on the number of machines, said Ed Trainor, vice president for fitness services at Town Sports International, yet many locations have been rearranged so visitors are greeted not with the sight of treadmills and TVs, but with green space the size of a the racquetball court. "It's the money shot," Mr. Trainor said.