As people age and find their mobility limited, or perhaps are recovering from an injury or surgery, is there an activity that they can enjoy and reap health and fitness benefits from without risk of injury or discomfort? Yes, says Jack Bolger, coach of the Stingrays, who has been in aquatics as a competitor, water polo player, life guard, and coach for more than 50 years, and the answer lies under the water, or at least in a pool.