The dean of aerobics guides takes a salutary stand for balance. Cooper (Aerobics, The New Aerobics Way, Aerobics for Women) isn't downgrading the importance of exercise, aerobics in particular; rather, we shouldn't think of exercise as a be-all of existence or a cure-all for our ills. Citing his own studies (at Dallas' Aerobics Center), the research of others, and anecdotal reports (the marathon runner who drops dead at 40 from a heart attack; the slob who coasts to a laidback 95 years), Cooper convincingly maintains that nutrition and emotional factors are equally vital in reducing our risk of developing some of the major killer diseases. The three, he points out, are interrelated: aerobic exercise has well-known beneficial effects on cardiovascular health; it seems to change the cholesterol level in the blood (also affected by diet); it increases feelings of well-being and decreases sleep disorders (possibly by the release of endomorphins--morphine-like substances--during strenuous activity). Cooper sets out general guidelines for a healthy diet, and for stress reduction, and then concentrates on helping readers design their own aerobics workouts to support these measures. Clear explanatory charts and tables abound, with Cooper's formulas included (so that those who don't exactly fit can work out their own figures). Sane, authoritative advice on how to exercise without making a fetish of it--with some new findings and suggestions on the overall benefits.