Now, fitness is such old hat that it's even had a backlash or two. Lots of the original ideas have been called into question, including the preeminence of aerobic exercise. But flexibility is bigger than ever; Pilates and yoga are two of the fastest-growing fitness programs in the U.S. in the early 2000s. The type of stretching Anderson recommends--called "static," meaning you sit in one place and hold the stretch for a specified amount of time--isn't exactly trendy, but it remains the most accessible way for entry-level exercisers to improve their flexibility. (Or, perhaps more important, to keep from losing whatever flexibility they have as they get older.)

Those who already have the version of the book that's been put out by Shelter Publications since 1980 won't find a whole lot that's new in this 20th-anniversary version. Some of the simple drawings by Anderson's wife, Jean, have been updated to show athletes in sport-specific outfits doing stretching routines, and there are more routines than before. The new edition includes routines for children, stretches to do in front of the TV, and some exercises to do before and after gardening. Plus, the old staples remain--stretching routines for all muscle groups, and pre- and postplay sequences for common sports (football, baseball, basketball) and a few uncommon ones (equestrian, motocross, rodeo). He's also created routines for sports that barely existed in 1980, such as snowboarding, triathloning, and inline skating.

The constant in Stretching is ease of use. Anderson doesn't need a lot of complex explanations because the drawings are so easy to follow. He makes it clear that stretching should make you feel better, not worse, and that it's not a competition. Any little bit you can do is better than not doing anything. That's a timeless message, which is why his book has been such an valuable reference for the past 20 years. --Lou Schuler