Push-ups make pin-ups. Hail the season of thighs and whiskers, of cinematic goliaths battling for box-office teeasures. Now Sylvester Stallone clinches with "Conan." And while the barbarian does his personal best against the contender "Rocky III" is a real knockout

It's the last chapter of his boxing fairy tale, says writer, directer and star Stallone. And it's as much fun as ever, a ground- meat-and-potatoes movie, with guys beating hell out of each other to a disco beat. Stallone pulls no punches; the familiar refrain features the "Rocky I" score, along with its characters and moral simplicity.

And for muscle-groupies, "Rocky III" is a four-layer beefcake. The top tier is the seven-foot, Nordic blond wrestler Thunderlips (Hulk Hogan), first to spar with Rocky this sequel. The civilized champ, out of sweatsuits and into Pierre Cardins, is doing American Express commercials, "The Muppets Show," and charity matches with the likes of Lips, a man whose kiss could suck out your brains. After bouncing Rocky on his head a few times, he tosses him into the fifth row. To the roar of the score, Balboa crawls back over the ropes and with one last grunt, heaves Thunderlips into the first row.

Next comes an encounter with the Incredible Hunk -- Mr. T., real-life winner of the bouncer contest on "Games People Play" and Leon Spinks' sparring partner. Mr. T. plays the uppity, ornery Clubber Lang, a "hongry" fighter with a nasty mouth. He challenges Rocky to a title bout, offers his wife (Talia Shire) something below the belt, and sends his feeble manager (Burgess Meredith) down for the count.

When the heavies meet in the title bout, Apollo Creed (Carl Weathers), smooth and sweet as Sugar Ray, is ringside, a colorcaster after losing to Balboa in "Rocky II." It's a conundrum, but Creed decides to train Balboa, his former nemesis and physical inferior, for a rematch with Clubber Lang. So it's off to the Coast for some toning up and grimacing "Chariots" style. Rocky and Apollo run through the surf together, learning, like Mariel Hemingway and Patrice Donnelly, that training together is the sweat bond of friendship.

Though Rocky's muscles are swelling, his confidence is not. He's hit the cerebral wall. Nothing will do but to let Talia Shire speak. She gives him a real talking-to, a speech on the beach that motivates him to get serious about his leg-lifts. It takes her about three minutes. Sure, that's unbelievable. But if you're looking for cinema verite, "Rocky III" is not for you. It's just a high for us punch-drunks. ROCKY III At 17 area theaters.