"It is a good, whole-body exercise that has low impact for people with arthritis, musculoskeletal, or weight limitations," says Robergs, director of the exercise physiology laboratories at The University of New Mexico in Albuquerque.
Water's buoyancy accommodates the unfit as well as the fit. Water cushions stiff joints or fragile bones that might be injured by the impact of land exercises. When immersed to the waist, your body bears just 50% of its weight; immersed to the chest, it's 25%-35%; and to the neck, 10%.Athletes use water to rehabilitate after injury or to cross-train. People with arthritis or other disabilities use water to improve fitness and range of motion and to relieve pain and stiffness.
Swimming is also desirable for people with exercise-induced asthma, humid air [around the pool] causes less irritation to the airways
