LaLanne, who became U.S. television fixture in his close-fitting jumpsuit starting in 1959 and came to be regarded as the father of the modern fitness movement, succumbed to pneumonia following a brief illness at his home in Morro Bay, along the California's central coast.
"He was surrounded by his family and passed very peacefully and in no distress ... and with the football game on Sunday, so everything was normal," Yvonne LaLanne, 66, told Reuters.
She said her father had remained active until a few months ago, including the taping of a recent public TV special.
Well into his 90s, LaLanne exercised for two hours a day. A typical workout would be 90 minutes of weightlifting and 30 minutes of swimming, changing his routine every 30 days.
He preached the gospel of exercise, raw vegetables and clean living long after his contemporaries had traded in their bicycles for nursing home beds.
"I can't die," LaLanne would say. "It would ruin my image."
LaLanne was born Francois Henri LaLanne on September 26, 1914, in San Francisco, the son of French immigrants. He said he grew into a "sugar-holic" who suffered terrible headaches, mood swings and depression.
In desperation when he was 14, LaLanne's mother took him to hear health lecturer Paul Bragg, who urged followers to exercise and eat unprocessed foods.
The young LaLanne swore off white flour, most fat and sugar and began eating more fruits and vegetables. By age 15, he had built a backyard gym of climbing ropes, chin-up bars, sit-up machines and weights.
Soon, LaLanne, who was only 5 feet, 6 inches tall, was playing high school football. He added weight-lifting to recover from a football injury and was hooked.
LaLanne opened the nation's first modern health club in Oakland, California, in 1936. It had a gym, juice bar and health food store. Soon there were 100 gyms nationwide.
Without bothering with patents, LaLanne designed his own exercise equipment, which he had built by a blacksmith. In 1951, he started using television to get the first generation of couch potatoes to try jumping jacks, push-ups and sit-ups.
"The Jack LaLanne Show," which went national in 1959, showed housewives how to work out and eat right, becoming a staple of U.S. daytime television during a 34-year run.
He also was known for a series of promotional fitness stunts. At age 45, in 1959, he did 1,000 push-ups and 1,000 chin-ups in 86 minutes. In 1984 a 70-year-old LaLanne had himself shackled and handcuffed and towed 70 boats 1.5 miles in Long Beach Harbor.
LaLanne said in 2007 his focus was always to help people the way Paul Bragg had helped him, adding, "Billy Graham is for the hereafter, I'm for the here and now!"