Now Heath is a walking muscle chart, as if lifted from the wall of biology class. He competed at the last Mr. Olympia at 248 pounds, a symmetrical knot of bulges on top of bulges in places that most men never dreamed of bulging. The bundle is cinched at a 29-inch waist.

When he flexes he expands, like a rippled blowfish. The front of his thighs are something a balloon artist with too many balloons might create. His arms look like gnarled oak. His relatively narrow shoulders, once a drawback, are broad knots of deltoids and trapeziuses. His back is a relief map of impenetrable terrain.

“I produce a three-dimensional effect that others don’t have,” he said.

Armbrust Pro Gym, owned by a friend and open to Heath at all times, is filled with thick-limbed men and more weights than machines. Its grunginess gives it an authenticity that Heath likes.

A wall is decorated with photographs and magazine covers featuring Heath. He pointed to one and noted the striations within his biceps. “Detail on top of detail,” he said. He pointed to his quadriceps and noted the “different dimensions of crevices.”

Heath’s girlfriend, Shurie Cremona, scrolls her phone for a photograph of Heath on stage next to another competitor at Mr. Olympia. One man looks like the most muscular man in the world. The other is Heath, who is more — how to put it? — striated and creviced.

People sometimes walk up and touch him, as if unsure if he is a man or a machine. What they do not realize is that beneath the stony exterior and self-assuredness is a squishy sense of anxiety and vulnerability. Heath gets nervous every time he strips to his posing trunks. He is rarely satisfied with what he sees in the mirror. He is persistently worried about imperfections others might find, too.