Michelangelo's statue of David -- created nearly 500 years ago -- still represents the ideal male physique -- tight waist, broad shoulders and a powerful chest.

When it comes to contemporary standards of male attractiveness, men are most dissatisfied with their whole upper body including the shoulders, biceps, triceps and pectorals, said Larry Tucker, director of health promotion at Brigham Young University in Provo, Utah. "For women, it's their lower body -- the waist, hips and thighs."

Not all men want the bulging, 55-inch chest of Lee Haney, who holds the professional body-building title -- Mr. Olympia. But clearly defined, well-sculpted chest and upper-body muscles that have some bulk are within the grasp of average men and women.

The chest muscles are divided into two categories. The pectoralis major -- a large, fan-shaped muscle --

covers the upper part of the front of the chest, and its main function is to move the arm across the body. The pectoralis minor -- a smaller, triangular muscle that lies under the larger chest muscle -- moves the shoulder blade up and down.

Although achieving taut, shapely pectorals is considered an exercise priority for serious body builders, health experts recommend more general muscle strengthening exercises for the average population.

"The idea of a big, broad chest is an image that needs to be refuted," said Kerry Stewart, assistant professor of medicine and a clinical exercise physiologist at Johns Hopkins University School of Medicine. "What is more important for adults is to involve themselves in a well-rounded exercise program that includes aerobics and muscular fitness."

Stewart believes that men should concentrate less on achieving the bulging biceps and pumped-up pecs of an Arnold Schwarzenegger, chairman of the President's Council on Physical Fitness, and more on using weights aerobically to achieve good health. To him, a better image would be Mark Spitz's firm, swimmer's body or tennis pro Ivan Lendl's trim form.

For women, "Madonna is a good female image," he said. "She has a taut body and good curves."

A realistic exercise goal for most adults is to use weights in a moderate way to develop muscle strength, decrease body fat, lower blood pressure and to look and feel better.

To work the chest muscles and upper body, fitness experts suggest a weight-lifting program that focuses on all the muscle groups, not just the pectorals. The bench press, performed by lying on a bench and lifting weights up to arms' length, is a basic exercise to develop chest muscles, said Lyn Jones, national director of coaching for the U.S. Weight Lifting Federation in Colorado Springs.

Beginning weight-lifters and middle-aged adults who are out of shape should start out slowly with light weights -- about 3 pounds -- and work up gradually. Some instruction in how to properly lift weights is also recommended. "If it took you 20 years to get out of shape, don't expect to get back into shape in two weeks," Stewart said. "In two to three months, you can expect to see some results."