Mal Whitfield (136), en roote to winning the gold medal in the 800-meter final of the 1948 Olympic Games. Immediately behind him is Arthur Wint of Jamaica, who won the silver medal. (AP)

Mal Whitfield, a record-setting middle-distance runner who won three Olympic gold medals in 1948 and 1952 and later spent many years as a U.S. Foreign Service officer and sports ambassador in Africa and elsewhere around the world, died Nov. 19 at a veterans’ hospice facility in Washington. He was 91.

He had heart disease and prostate cancer, said his daughter Fredricka Whitfield, a CNN news anchor.

Mr. Whitfield, who was also a member of the acclaimed African American military unit in World War II known as the Tuskegee Airmen, had never competed internationally when he qualified for the U.S. Olympic team in 1948.

At the Summer Games that year in London, he won a bronze medal in the 400-meter race and a gold medal at 800 meters, setting an Olympic record of 1 minute 49.2 seconds as he charged ahead of his competitors over the final 100 meters on a rain-soaked track.

On the final day of the Olympics, before a crowd of 83,000 at London’s Wembley Stadium, Mr. Whitfield ran the anchor leg for the 4-by-400-meter relay team to win a second gold medal.

Mal Whitfield holding his gold medal in 1948. (AP)

By the time the Olympians sailed back to the United States, Mr. Whitfield had acquired a new nickname: “Marvelous Mal.”

With his long, elegant stride, Mr. Whitfield would remain a dominant force in running until the mid-1950s. He served as an Air Force sergeant during the Korean War and went on more than 25 bombing missions as a tail gunner. He trained for the Olympics by running on an airfield between military assignments.

At the 1952 Summer Olympics in Helsinki, Mr. Whitfield went on to win two more medals, including a gold in the 800 meters, tying his Olympic record of 1:49.2 from four years earlier. He also ran a leg on the U.S. 4-by-400-meter relay team, which won a silver medal. He was the first active-duty member of the U.S. military to win an Olympic medal in track and field.

The grueling experience of training for the Olympics while serving in combat was “the most miserable time in my life,” Mr. Whitfield recalled in 2006.

Mr. Whitfield, who was orphaned at a young age, grew up with a sister in the Watts section of Los Angeles. He was inspired to take up running after seeing African American sprinters Eddie Tolan and Ralph Metcalfe at the 1932 Olympic Games in Los Angeles.

Four years later, he watched Jesse Owens compete at a Los Angeles track meet, shortly before the indomitable sprinter and long jumper won four gold medals at the 1936 Olympic Games in Berlin in front of Adolf Hitler.

Mr. Whitfield later befriended Owens, who encouraged him to attend Owens’s alma mater of Ohio State University.

“He and Jesse Owens were probably the two smoothest runners that you could possibly want to see,” Harrison Dillard, the Olympic 100-meter champion in 1948, told the Team USA Web site in 2012. “Of course, they ran different events — one was a sprinter, one was a middle-distance runner — but Mal, his stride was so long and graceful and effortless, I’ve never seen anything like it.”

Mr. Whitfield, who stood 6 feet tall and weighed 168 pounds, ran every distance from 200 meters to 1,000 meters. Sportswriters marveled at his “nonchalant grace” on the track and the “flawless rhythm of his running style.”

His favorite event was the half-mile, or 880-yard run. (Its metric near-equivalent is 800 meters.) From 1946 to 1955, Mr. Whitfield won 66 of 69 races at that distance. He set six world records at various distances, including twice in the 880, with a career best of 1:48.6 in 1953. His fastest time in the 400 meters was 45.9 seconds.

In 1954, Mr. Whitfield became the first African American to win the James E. Sullivan Award, presented each year by the U.S. Amateur Athletic Union to the country’s top amateur athlete. He was named to the U.S. National Track & Field Hall of Fame in 1974 and to the U.S. Olympic Hall of Fame in 1988.

After failing to make the Olympic team in 1956, Mr. Whitfield retired from running and began a long career as a coach and athletic adviser around the world, particularly in Africa. He joined the U.S. Foreign Service in 1963 and spent decades coaching and developing sports and education programs as an athletic ambassador of the State Department.

In a 37-year career with the Foreign Service, Mr. Whitfield conducted sports clinics in more than 130 countries.

“Sports is about friendship, woven into education,” he said in 2006. “It is the international language.”

Malvin Greston Whitfield was born Oct. 11, 1924, in Bay City, Tex., and moved as an infant to Los Angeles. Both of his parents died by the time he was 12.

He joined the Army Air Forces during World War II, then entered Ohio State University in 1946, winning the NCAA 880-yard titles in 1948 and 1949, as well as several indoor championships.

After his Air Force service, Mr. Whitfield completed his college degree in 1956 at California State University at Los Angeles.

In addition to training athletes when he was with the State Department, Mr. Whitfield was instrumental in establishing an educational exchange program that enabled thousands of African students to study at U.S. universities.

After retiring in the 1990s, he settled in the Washington area and led an educational foundation. He published an autobiography, “Beyond the Finish Line,” in 2002.

His first marriage, to Mary Adams, ended in divorce.

Survivors include his wife of 57 years, Nola Simon Whitfield of Silver Spring, Md., and their three children, Nyna Konishi of Germantown, Md., Malvin Lonnie Whitfield of Washington and Fredricka Whitfield of Atlanta; a son from another relationship, Ed Wright, a nationally ranked high jumper, of Berkeley, Calif.; eight grandchildren; and four great-grandchildren.

During Mr. Whitfield’s years overseas, he lived in and coached in every African country. He helped develop the careers of many prominent African track stars, including two-time Olympic champion Kipchoge Keino of Kenya, 1968 marathon gold medalist Mamo Wolde of Ethi­o­pia and Uganda’s John Akii-Bua, who won the 1972 Olympic gold medal in the 400-meter hurdles.

“He’s like a god over there,” onetime Olympic sprinter Steve Riddick told USA Today in 1996.

Even though he was seldom recognized in his homeland, Mr. Whitfield had few regrets about the direction his life had taken.

“I’m richer in soul and mind than a millionaire,” he said.