Bob Douglas fled his wheelchair on horseback. Since then, the 50-year-old Washingtonian has forged a path for 4,000 physically and mentally handicapped children and adults at the National Center for Therapeutic Riding in Rock Creek Park.

For 16 years, the Howard University graduate worked as a researcher at the National Institutes of Health, where he helped discover a means of detecting rubella in pregnant women and children. But in 1972, Douglas began to feel weakness in his limbs. He had multiple sclerosis.

He lost the use of his legs and much of his vision, and retired from NIH. At home, the wheelchair-bound Douglas realized he could make a dream come true. He had worked at the stables in Rock Creek Park, and when he learned that the stable concession was for sale, he bought it. Then, with a special ramp from which he could mount, he began to ride.

As he did, he noticed his strength returning. He went on to found the therapeutic center in 1973, and in 1974 he began to walk again.

Today he spends 9 to 10 hours a day at the center, teaching riding and overseeing administration, and he has traveled to Italy, West Germany, France and Peru to lecture on therapeutic riding.

The pain in his legs varies. When it gets severe, he rides Blue, the horse he has ridden since he first climbed from his wheelchair. "Normally, when the staff sees me riding they know I'm at low ebb," he said.

Perhaps the center's best-known student is Jim Brady, the White House press secretary, who was shot and disabled in the 1981 assassination attempt on President Reagan.

"It's helped my balance a great deal," said Brady, who rides a pinto named Birney at NCTR. "And my physical therapist has said that I can do things on the horse that I can't do on the mat."

Douglas is "quite a fellow," Brady said. "He knows his craft and he knows his horses."

The center, just off Military Road in the middle of the park, has six full-time instructors and about 60 volunteers, Douglas said. An individual lesson costs $18 per half hour, which covers about half of its cost. The center depends on donations and grants for much of its funding.

It recently has allied itself with the Washington Healthcare Corp. and the National Rehabilitation Hospital. "We will cosponsor demonstration studies to better understand the benefits of therapeutic riding for the handicapped," said hospital President Ed Eckenhoff.

Riding provides both mental and physical stimulation, said Douglas, who has monitored riders' progress since the center opened in 1973.

"What makes the horse work is that it takes the student out of a clinical setting and into a recreational setting," he said.

In addition, "the kinetics that go along with the movements of the horse can't be duplicated" in therapy, Douglas said. "The horse is pulling you through," stretching and using muscles that can't move themselves.

"People who are disabled have lost control over things," he continued. "And here is a 1,000-pound animal. And if you can have control over something that large, which has a mind of its own, you can regain a sense of control," he said.

Douglas said he first rode a horse "when I was 12 years old, in the same place I am now.

"At that time, we -- we being blacks -- were not allowed to ride. So I cleaned stables, mucked stables," in exchange for the occasional ride, he said.

"My dream was to get the [stable] concession from the Park Service. And my dream has come true," Douglas said.

Douglas thinks students at NCTR feel something special, too. "Most of these kids believe that only kings and queens ride horses. So for them to be up there, especially when they have a disability . . . you can imagine how they feel."

In 1984, Nancy Reagan dedicated an indoor riding facility at NCTR. Douglas said he hopes some day to add classrooms and space for examinations and therapy.

"We've had a lot of autistic kids, who don't communicate. And for them to call out 'Jigsaw,' or 'Buster' . . . . Or if you see someone come in on walkers, then in six or seven months see them walk, it's very, very, exciting.

"And the mentally retarded and learning disabled are so motivated to learn about horses," he continued. "It seems to help reading, vocabulary, spelling or math. To learn the breeds and colors means a lot.

"It is very easy for someone to find himself in a wheelchair and stay," he said. "The doctor says, 'You'll never walk again,' and you take it at face value. No matter what the disability is, you should try."

Toni Carter and Phyllis Carney bring a class of emotionally disturbed children from Turner Elementary in Southeast to the stables each week. "There is more of a team spirit; the students are getting along better," because of their riding, said Carter. "They know how to ride a horse, and not everyone can do that. They are proud of themselves," she said.

One of the students, Chad Smith, 13, took a trot, patted his horse, and said softly, "All right. That's a nice horse." Renee Evans, 11, on only her third visit to NCTR, smiled more broadly with each turn. After dismounting from her horse, she said softly, "I love him."

"I like riding the horse. I like how he can control himself and not get mad," said John Butler, 10.

After a few rounds, instructor Annette Becke told the students, "Give your horse a hug or a pat, whichever you think it deserves." Six pairs of little arms encircled six high, strong necks.

Just outside the corral, Bob Douglas watched and was pleased. "When I first came down with MS, I used to curse it and ask, 'Why me?' " he said. "Over the years, I think I've come to see why me. There is no better reward than to help other people, and that is what I am doing. This may have been a blessing in disguise."