LAKE STEVENS — He calls himself a “scrawny old guy.”

Others call him He-Man.

What’s up with that?

Roger Sweet, 84, was a preliminary designer of Mattel’s brawny Masters of the Universe characters, which made mincemeat of the other toys on the market in the 1980s. He helped develop the exaggerated muscles, battle action stance and swivel waist for his alter-ego He-Man — the most powerful man in the universe.

“I always wanted to be a He-Man and never could,” he said. “I knew almost every guy in the world would love to be a He-Man.”

Sweet is soft-spoken, with thinning hair and aviator glasses. He drives a white 1990 Honda Accord with 265,000 miles.

At 5-feet-10 and 155 pounds, he’s hardly a He-Man.

Sweet’s stature was a factor since boyhood.

“At age 13, I was 4-foot-11 and weighed 88 pounds. At age 14, I grew 10 inches and weighed 105 pounds. Then I went out for high school football. The coach cut me off the team without even seeing me play, because I was so scrawny,” he said.

“In college I could do 140 perfect push-ups. But I was always very much aware that I was a puny guy.”

Sweet, an Ohio native, graduated from the Institute of Design in Chicago. In 1972, he went to work as a toy designer at Mattel in California.

One project was to work on the next toy craze for boys.

“Mattel market research found the three most popular things were barbarian fantasy, futuristic military as in Star Wars, and current military as in GI Joe,” Sweet said.

“I took this 9-and-a-half-inch figure and I glued him in an action pose and I widened his shoulders. A lot. Then I added a huge amount of clay to him.”

As Sweet tells it: “I originated and named He-Man. I originated the three prototype models that brought He-Man and Masters of the Universe into existence.”

Sweet was part of a large team. Overall, he played a small but mighty role in the Masters of the Universe toy franchise. Characters include evil lord Skeletor, princess of power She-Ra, and fighting tiger Battle Cat.

Regardless of who did what, the rest is history, and 40 years later Sweet’s name is all over the internet.

The Masters of the Universe superheroes took the boys’ fantasy world by storm for several years of He-Mania. There was a toy line, cartoon series and comics.

He-Man didn’t make Sweet a rich man.

“Three years in a row, midway through managing the original series, I got 50 percent of my salary as bonus from Mattel,” he said.

After He-Man, he worked on the fashion accessories for Barbie, a reigning cash crop for Mattel.

“I wanted a change in design approach,” he said.

He left Mattel in 1991.

With his nephew, he later co-wrote a book, “Mastering the Universe: He-Man and the Rise and Fall of a Billion-Dollar Idea.”

That didn’t make him rich, either.

He and his wife Marlene lived in California when they visited a friend in Snohomish and were smitten by the area. They moved to the Lake Stevens area in 1992. The Honda is a hand-me-down from their son, who lives in Arizona. “I got that car in 1997 with 90,000 miles on it, and I’ve been driving it ever since,” Sweet said.

Sweet keeps a low profile, other than an occasional appearance signing He-Man merchandise. Over the weekend, a line of people snaked around the BobaKhan Toys & Collectibles store in Everett for Sweet’s autograph.

Most of Sweet’s time is devoted to his fitness regimen.

“I work out six days a week, for an hour-and-a-half a day. I spend 45 minutes of that doing stretching exercise, the other 45 doing cardiovascular stuff,” he said. “I do it to keep from taking a long-term dirt nap.”

At the Lake Stevens Anytime Fitness, other regulars know him as “He-Man.”

Last week, he did 23 pull-ups before hitting the treadmill. He also did a few battle-action punches upon request, complete with a raised voice “Bam!”

“Everybody knows Roger, and has heard his story,” said Lyndell Duston, club manager. “He’s so enthusiastic, and that brings a lot to our facility.”

Sweet was diagnosed with follicular non-Hodgkin lymphoma at age 64 in 1999.

“I had it at the most advanced stage,” Sweet said.

He underwent two years of rigorous chemotherapy, plus intensive radiation treatments.

He won the battle and still triumphs 20 years later.

Wouldn’t that make him a He-Man?

“I would say more like a lucky man,” Sweet said.

Or as He-Man would say: “I have the power!”

Andrea Brown: abrown@heraldnet.com; 425-339-3443. Twitter @reporterbrown.