On the reasonable premise that exercising with someone could be pleasanter than exercising alone, Gregor has designed a graduated series of warm-up, strengthening, stretching, and cool-down exercises that involve resistance work and/or interaction with a partner. Cardiovascular exercises are also included (jogging in place side-by-side, for instance), along with a program for solo exercise for the days he or she can't make it. There are a few tips on eating properly too. Some of the routines involve pretzel-like couplings (""Your partner lies flat on his back while you stand facing him, your feet tucked under his ankles. Keeping his upper arms on the floor, he reaches up. . .""). But this isn't just fun-and-games, Gregor reminds us: ""The program is a shared adventure toward excellence."" Fair enough, either way.