As Carlos Van Leer describes it, "I hit the high point of my life and, well, not the low point, but low enough. And all in one day."

The high point was the sort of acclaim most of us only dream about. On the stage of the Regency Ballroom of the Shoreham Hotel, before a cheering audience of several hundred, Van Leer, a 74-year-old moped enthusiast from Chevy Chase, received a national achievement award from the President's Council on Physical Fitness.

Master of ceremonies Art Linkletter shook Van Leer's hand and joked with him. The assembled throng stood and applauded several times. It was total adulation.

Then, just two hours later, the flip side:

"I was listening to the tape of Linkletter and me at home and I got so steamed up that I jumped out of the chair and tripped on the phone wire. I crashed like hell."

The damage was a shattered right hip, which had to be surgically replaced with a steel substitute. The prognosis is good, although "the doctors aren't encouraging about my future on a moped," said Van Leer, who averages 6,000 miles a year on his.

Still, the real damage was that Carlos Van Leer, for years one of Washington's most active people (antiwar movement, church work, accordion performances, sex-education crusader and many other roles and projects) was confined to flat-on-his-back status in Bethesda's Suburban Hospital.

"Yes, sure, sure, come out and see me tomorrow," said the always-wry Van Leer. "I'll try to save a place for you on my busy schedule."

But the scene in Room 432 was anything but gloomy.

The place was positively lousy with colored balloons. The bulletin board bore a sign that read: "Make 'Em Laff." And Van Leer celebrated the arrival of his visitor with a rollicking sea chanty on the accordion he keeps beside his bed. He sang so loud in accompaniment that nurses peeked in to see if something was wrong.

"What can you tell the people about me? Tell them that I've asked the Almighty to stand by. No Van Leer to claim yet, thank you very much.

"And tell them that after a day like that one of mine, I believe in irony. Whenever something good happens, that's the time to look out."