Americans focus on trim waistlines.

Blame fashion with its cropped sweaters, T-shirts, and hip huggers or the navel-baring females of "Friends" and the buffed-body bathing beauties of "Baywatch." Whatever the reason, today's fitness-conscious Americans have their eyes on the midsection and are looking for "washboard" abdominal muscles. In a survey conducted by MarketFacts for NordicTrack Inc., 60% of respondents selected the abs as the area of the body they would like to tone the most. The rest of the body trailed by considerable margins, with 14% of the vote going to the legs, while the arms and buttocks received 9.5% and eight percent, respectively.

Fitness expert Gin Miller is not surprised by the results. "A toned abdomen is often seen as the sign of ultimate fitness," she points out. For men, the abdominal area can be a resting place for fat, while women seem to worry most about their lower abs--especially after child-bearing. In either case, strong abdominals can be the most challenging to maintain.

Beyond analyzing their own bodies, survey participants rated the abs of some male and female...