Done correctly, water workouts can give you gains similar to those on land, including aerobic fitness, muscular strength and endurance, flexibility and better balance. Darcy Reber, family medicine provider at Mayo Clinic Health System in Cannon Falls, Minn., recommends aquatic exercise because: Water's buoyancy supports your weight. When you're submersed up to your neck, the water cancels out about 90 percent of your body weight, significantly reducing stress on your weight-bearing joints, bones and muscles.