Unlike the eat and grow slim approach to diet books or the swinishly lazy approach to exercise books, the message here about physical fitness is tough -- Mr. Cureton says you have to work at it; that it can't be achieved on an occasional basis or in just a few minutes sneaked in isometric isolation. He recommends at least an hour every day for the series of exercises he's developed after years as Director of the Physical Fitness Center at the University of Illinois. Additionally, you should do a lot of walking and have daily plans for swimming, regular workouts etc. The exercises outlined in the book require no equipment beyond the general household furnishing and your own flabby muscles. They are listed in a series of ten for each day requiring at least five minutes a piece. The general tone of the remarks indicate an older audience for this short book. Mr. Cureton believes that it's never too soon to start keeping in trim and never too late, either. The time factor will not appeal to those seeking an easy way out but the statistical evidence on which these programs are based would be difficult to deny.