In 1998 Joe Glass took up water aerobics in his mid-80s to soothe his aching joints. Never halfhearted about activities he enjoyed, he soon began training as an instructor and earned his certification.

The improbable result was that well into his 90s he was a popular coach of aquatic exercises at several swim venues, primarily the J.M.Tull YMCA in Lawrenceville.

Phyllis McCarthy of Lilburn, a water aerobics enthusiast for 25 years, said Mr. Glass was one of the best instructors she ever had. He led intense workouts, she said, but he infused them constantly with words of encouragement.

"Joe was larger than life," said Linda McLemore of Lilburn, herself a water aerobics instructor. "He could be very personable, but when class began, he was all business -- he'd chide latecomers and discourage chit-chat."

As recently as three months ago he was swimming laps, she said, adding, "He was amazing."

At one time nearly incapacitated by arthritis, Mr. Glass came to find he could lead nearly a dozen arduous hourlong exercise classes a week.

As he told an Atlanta Journal-Constitution interviewer in 2001, "People need to understand what [working out in the] water can do," he said. "Eighty-percent of your body weight is off in the water. It is not beating up on you, even though it is heavy-duty exercise."

In 2004 Atlanta was included in the worldwide Olympic torch relay that preceded the Games in Athens, Greece, and Mr. Glass, who was 90 years old at the time, was selected to be one of the torch bearers.

His daughter, Susan Ray of Loganville, said her father cherished the day — June 18, 2004 — when he carried the torch through Piedmont Park. She said she feared the incline her father had to traverse would be hard on his knees. In fact, she said, he managed to maintain a brisk pace, and he reveled in the cheers of "Go Pah-paw! Go Pah-paw!" that his great-grandchildren chanted along the way.

Joseph F. Glass Sr., 98, of Snellville died of pneumonia July 3 at Embracing Hospice, Snellville. A memorial service will be at 2 p.m. Sunday at Smoke Rise Baptist Church in Stone Mountain. Cremation Society of Georgia is in charge of arrangements.

Born in 1924 and raised in Memphis, he found work in 1938 in Morristown, N.J., as one of America's early trainers of guide dogs for the blind. A few years later, while serving at an Army facility in Arizona, he trained horses. "Dad always had a way with animals," his daughter said.

In 1940 he enlisted in the Army, serving for seven years and leaving at the rank of master sergeant. Besides training horses, he was a guard at a camp for German prisoners of war and a laboratory technician at military hospitals.

The latter experience helped prepare him for a long career in hospital management with the VA, during which he and his family moved nearly every three years from one assignment to another across the nation, his daughter said. His final job was as assistant director of the Veterans Medical Center in Memphis.

Over many years he acquired antique clocks, gathering one of the largest such collections in the Southeast, his daughter said, and enough knowledge on the subject that he became a frequent lecturer at gatherings of collectors.

At Smoke Rise Baptist, he taught a Sunday school class for young adults. In addition, after 64 years of marriage to his wife Grace, before her death in 2003, he counseled young couples at his church.

Also surviving are a son, Joseph Glass Jr. of Little Rock; seven grandchildren; and eight great-grandchildren.