Boris Vallejo and Julie Bell are fantasy art rivals.

They're also married -- a big leap from the days when Julie, a professional bodybuilder from Texas, was one of Boris' models. Now that Julie (who, like Boris, signs her work with a first name only) has found a niche for her own distinctive painting style, they serve one another as both cheerleader and critic.

"We both see each other's work differently than we see our own," she said during a telephone interview from their Allentown, Pennsylvania, home.

"Painting is a very lonely profession," said Boris, a native of Peru who began illustrating ads for a New York City retail chain in 1964. "You sit in your studio for days and days and days," he said. "Now I have somebody who loves this as much as I do, and who understands me like I understand her. At the same time, we are very competitive. We spur each other to try harder. ... Sometimes I look over my shoulder to see what she's doing."

Boris' work in the '70s, largely for comics and paperbacks, redefined the fantasy art genre. His fame, Julie said, is an incentive to excel.

"I don't want to look shabby next to anybody, and neither does he," she said. "We push each other."

The couple has never collaborated on a painting, but both have produced portraits for a new series of Marvel Comics trading cards. Boris said he never expected to return to comics, but his interest was rekindled by his wife's work. "I had lost touch with comics for many years," he said. "I was really flabbergasted to see how the industry has improved."

For Julie, work as a bodybuilder and model sparked a career in the arts. "I definitely always wanted to be an artist, but I never thought I'd be a professional," she said. "It's such a mysterious profession. I had no idea how you actually become one."

Working with Boris made her examine her own painting more seriously, she said. In fact, an experiment with one of Boris' early techniques has become a Julie Bell trademark: "metal flesh," lifelike beings whose steel skin flows and flexes like muscle.

Muscle is a key concern for both artists, who casually bring to life heroes and deities, usually engaged in superhuman, muscle-popping tasks. Male and female bodies -- often sparingly clad to emphasize every curve and muscle in stunning detail -- are idealized in Olympian form. "To me, it's the most beautiful creation," Boris said. "It's always been a fascination for me."

Boris denies that the bulging biceps and ample bosoms are unrealistic. He and Julie often use bodybuilders -- including each other -- as models. "My live models look very much the way I paint them," he said. "We're almost talking about a different species, the elite of human bodies."

Both also paint mythical and alien beings, creating believable creatures from their knowledge of body mechanics.