President John F. Kennedy's back problems have been the subject of much speculation, but the true story was never reported — until now. Susan Schaller of Wilton, who writes as Susan E.B. Schwartz, has written a book revealing the untold story and its many layers in her new book, JFK's Secret Doctor, (Skyhorse Publishing, 2012).

Ms. Schaller, who will give a talk at the Wilton Library on Monday, Dec. 10, from 6 to 7 p.m., said her book focuses on Dr. Hans Kraus, a "medical visionary and rock-climbing legend." He was President Kennedy's back specialist, and actually declared him cured after two years of treatment.

"President Kennedy was playing golf and feeling much better," she said.

A freelance writer and former rock climber who contributes to national adventure and sports magazines, Ms. Schaller said she met Dr. Kraus when she did a profile of him for Rock and Ice magazine.

"He was fascinating and I thought he would make a wonderful subject for a book," she said. Ms. Schaller and Dr. Kraus became lifelong friends "to the point that I was at his deathbed with his family in 1996," she said.

Her book, which received a "starred review " from the noted reviewer Booklist, also received praise from Mike Wallace, the late 60 Minutes journalist. He described her book as "fascinating! Just fascinating! What a story. Kraus was back doctor to all kinds of stars, athletes, politicians, show business personalities, even journalists. Anyone who was anyone went to Kraus."

So what was the true story about President Kennedy's back problem, which was kept secret from the public at that time?

Ms. Schaller said his chronic pain was actually caused by "back muscles that were too weak and too tight." Although President Kennedy's well-known injuries caused by the sinking of PT 109, the boat he captained in the Pacific in World War II, "might have been a contributing factor, along with his Addison's disease," his tight back muscles were the actual source of his extreme discomfort.

"The problem was also probably exacerbated by President Kennedy's stress," said Ms. Schaller.

To relieve his pain, Dr. Kraus prescribed a regimen of his K-W exercises, an innovative strategy at that time. "President Kennedy did the exercises at least five times a week for an hour, from October 1961 to October 1963 — when Dr. Kraus declared him cured."

Ms. Schaller described the exercises as "very gentle, not the kind you would do if you wanted to compete in the javelin throw at the Olympics, but very effective."

Chillingly, Dr. Kraus told President Kennedy to stop wearing his back brace "because he believed it weakened his muscles," Ms. Schaller said. President Kennedy promised he would do so in January 1964, and historians, including James Reston, have theorized he might have survived his assassination in Dallas if he had not been wearing the brace, according to Ms. Schaller.

The back brace was made of "steel rods" and held President Kennedy upright, so that he remained stationary after the first shot in Dealey Plaza, instead of slumping forward, she said. "He was completely motionless, a sitting duck" for the fatal second shot, Ms. Schaller said.

Her interviews with Dr. Kraus are now archived at the Kennedy Library in Boston, and Dr. Kraus's once secret medical records are now also available to the public at the Kennedy Library.

After working with Dr. Kraus, President Kennedy became a "convert" to the importance of exercise and physical fitness and worked with him to issue his "President's Physical Fitness Challenge" for American children, Ms. Schaller said.

"He had great respect for Dr. Kraus, who was a fantastic athlete, known for hair-raising ascents on two continents," she said.

In turn, Dr. Kraus, who had voted for Richard Nixon in the 1960 presidential election, became an admirer of President Kennedy. "Dr. Kraus was very captivated by him, and his vision for our country," she said. "He would not have treated anyone he didn't like. In fact, after President Kennedy was assassinated, he refused to treat Lyndon Johnson, who he did not like."

As for Ms. Schaller, she said she no longer rock climbs because her two children, Grace, 13, and Matt, 10, are her priority.

Information: 203-762-3950, or wiltonlibrary.org.