George Allen has finally found something in life to replace the Cowboys game.

"Oh, I miss football," said the former Washington Redskins coach, "but this is bigger and better than beating Dallas."

Allen was talking fitness, specifically the lack of it among U.S. youth, and his plan to correct that by exposing to the nation the frailty of American youngsters compared with their counterparts in the Soviet Union.

As chairman of the President's Council on Physical Fitness and Sports, Allen is beating a fitness drum across the nation, pushing a new program to test 20,000 American youths by tough Soviet fitness standards while the Soviets test 20,000 of their young the U.S. way.

When it's over, in 1988, he expects to be able to show that the youth of America are so weak they're in danger "of injuring themselves falling off the chair while they watch TV."

Not so Allen. At 65 he looks like 50 and completed his first marathon in March.

These days, Allen runs 10-kilometer races in 45 minutes, bike-rides 30 miles in under two hours, does mini-triathlons, plays basketball, swims, lifts weights and tries to interest the youth of America in fitness.

"When I go out to run in the morning, I see kids waiting at the school bus stop. They're still there 20 minutes later. They could have walked to school in that time.

"The kids I tested in the Soviet Union took our {President's Council} test and breezed through it," he said. Meanwhile, 125 youngsters from four area schools plugged along valiantly with the Soviet Union's fitness test at Gallaudet University. In quick, partial testing, 70 percent rated acceptable by Soviet standards, considerably better than the 55 percent Allen got when he ran the same test two weeks ago in Los Angeles.

Allen said the problem is that in the last 20 years many U.S. school systems, particularly poorer, inner-city ones, have all but abandoned physical education for cost reasons.

He said just two states, Illinois and New Jersey, have mandatory physical education in all grades. His goal is to restore nationally a standard of one hour a day of supervised fitness and sports activity for all grades.

While kids from Fairfax High School, Brent Elementary in D.C. and schools in Baltimore and Cockeysville, Md., huffed and puffed through 2,000- and 3,000-meter runs, ball throws, long jumps, pull-ups and other assorted Soviet tests, President's Council staffers handed out gloomy "fact sheets" that maintained, among other things:

Half of U.S. school girls ages 6 to 17 and 30 percent of boys 6 to 12 can't run a mile in less than 12 minutes, just over walking speed.

Fifty-five percent of girls 6 to 17 and 25 percent of boys 6 to 12 can't do one pullup.

Forty percent of children aged 5 to 8 show at least one potential heart-disease factor (obesity, high cholesterol, high blood pressure).

Most of the youngsters came in hopes of seeing President Reagan, who could not make a planned visit.

Instead, they got the old coach, who said, waving his arms, "Look at those kids. Most adults could wipe 'em out. I could wipe 'em out."

With that, Allen stripped down to shorts, ran 13 laps on the quarter-mile track, popped off 30 quick pushups and complained, when TV people dragged him off for a late interview, that he wasn't finished with his workout yet.