Because of the imaginative musings of a lonely runner, Dan Pastorini's broken ribs hurt only when he laughs.

Now jogger Byron Donzis is designing a flak helmet for pro basketball player Rudy Tomjanovich, a jacket for. Washington Capitals with battered rib cages and, perhaps most important of all, an inflated encasement and inertia gear to prevent knee injuries.

His trouble had been, he said, he couldn't get anyone's attention. Then, Houston Oiler fan that he is, he approached them with the offer of a flak jacket that would enable Pastorini to play with three broken ribs, Tim wilson with two, and Earl Campbell, Carl Mauck and Gregg Bingham with one each.

"I'm an inventor," Donzis said yesterday during a telephone interview, "and there are so many 'crazy inventors.'" He said, however, he has "done tremendous physical research on the whole concept of air cushioning."

So, Donzis tried to get Pastorini's attention with a 2-by-4, sort of.

"He had an unmarked room at Methodist Hospital," Donzis said. "I went there with an associate. He was carrying a baseball bat and I had my flak jacket. The fifth floor nurse stopped us. She probably thought I was going to beat Dan to death.

"I pleaded with her to open the door. "Greg Sampson (Oiler offensive tackle) was in the same room with Pastorini, and Dan was irked as I made my proposal.

"I put the jacket on, I put my hands above my head, and my associate (6 feet and 185 pounds) hit me as hard as he coule with the bat four or five times in the area where Pastorini said his ribs were sorest. I got every-body's attention."

Donzis said the air-inflated jacket has no sleeves, resembles a bullet-proof vest and weighs only 5 1/2 ounces. Donzis said the players first exhibited "a touch of vanity about how it might increase their profile," but as they got away from the thought of looking like the Michelin (Tire) man reality about its protection prevailed.

"It hasn't hampered Pastorini's throwing," Donizis said. Pastorini completed 20 of 29 passes against Miami and 12 of 15 against New England. "He seems to be throwing with more confidence than he has in several years," Donzis said.

"The protection will make football more exciting, because the players will take more chances. A player will not hesitate to leap for a pass, even though he knows he will be hit from the blind side. He'll know it won't hurt, so he won't care."

Donzis made a jacket for Earl Campbell, who declined to wear it because he's so tough, Donzis said.

The inventor also has a new knee brace that he said works on the principle of an inertia gear, similar to an automobile shoulder belt. It gives with slow pressure, but it stops with a sudden jerk, he said. Protection is maintained if a player's knee is hit from the side, but normal movement is still allowed.

Donzis' next project is to design a soft helmet to protect the wearer and spare opponents the effects of spearing now associated with the hard plastic helmet.