Members at Curves, a fitness center designed exclusively for women, rotate around a circuit of hydraulic resistance machines that have been designed to work with female bodies and promote weight loss, protect against osteoporosis, and deal with arthritis. An experienced trainer is always nearby to help manage participants’ machine maneuvering and muscle making. Instead of fiddling with weight stacks and losing momentum, the hydraulic machines use your own body weight, fitness level, and aerodynamic water bottle to create resistance that matches abilities, decreasing the risk of soreness or injury. Because traditional lift-and-lower motions create bulky muscles, each machine uses push-and-pull motions to create toned, lean muscles perfect for crushing a grapefruit without looking like you can.