Heuga died Monday at Boulder Community Hospital in Colorado, said University of Colorado ski coach and longtime friend Richard Rokos. He said Heuga had recently been dealing with respiratory problems.
At the '64 Olympics in Innsbruck, Austria, Heuga finished third in the slalom, just behind fellow American Billy Kidd. They were the first U.S. men to win medals in skiing. Josef "Pepi" Stiegler of Austria won the gold.
"There wasn't any pressure on us," Heuga told the Denver Post in 2006. "There were no expectations. We had no track record. But yeah, I accomplished one of my dreams."
U.S. Ski and Snowboard Assn. President Bill Marolt, who skied with Heuga on the 1964 Olympic team, called him "a champion in every sense of the word."
Born in September 1943 in Tahoe City, Calif., to a Basque immigrant and his wife, Heuga grew up in Squaw Valley, Calif., where his father operated the cable car. He learned to ski as a toddler, made the U.S. ski team at age 15 and won the 1963 NCAA championship in the slalom for the University of Colorado.
In 1968, Heuga and Kidd were pictured on the cover of Sports Illustrated before the Olympics at Grenoble, France. Heuga, who finished eighth in 1968, was diagnosed with multiple sclerosis in 1970. The effects of the disease eventually confined him to a wheelchair.
"He was the personification of determination and never giving up; he inspired so many people," Kidd said in a statement from the U.S. ski team. "Jimmie's accomplishments on the race course will forever be remembered. But it's his accomplishments and drive in the fight against MS that will continue to help so many people live their lives. His life is an inspiration."
In 1984, he founded the Jimmie Heuga Center for Multiple Sclerosis, a nonprofit group now called Can Do Multiple Sclerosis.
"He was a very strong man and an inspiration to so many people in the ski world and the medical world," said Heuga's wife, Debbie. "He's skiing the hills of heaven right now."
Heuga was inducted into the United States National Ski Hall of Fame in 1976.
In addition to his wife, he is survived by their three sons and a daughter from a previous marriage.