Everyone is wrong about exercise, Wiener contends--until all America swims 40 minutes a day, we're robbing ourselves of the ""most perfect, safest, most relaxing and most rewarding exercise we could ever hope for."" This is a why-to, not how-to book; and physical considerations are skimmed over while the author gives us page after page of personal testimonials to the mental and psychological benefits of swimming. Wiener's approach is relaxing (""You're in the water for fitness and peace of mind. So what if your kick is lopsided"") and he sticks to his subject; but he makes his point over and over again. ""Fluid in Mind"" (""Why You'll Like Yourself More""), ""Swimming to the Inner Self"" (""Sensory Dialectic""): for Wiener it all comes back to the psyche--readers may prefer more about the physcal. Some of this is homey (what Wiener carries in each compartment of his swim bag); some of it is awful (""water bristles with sexuality""). And some of the information on physical conditioning (he pooh-poohs the danger of overstress) is debatable. The main attraction here is the emphasis on mental benefits, and it gets very tiresome.