The 4-Hour Body: An Uncommon Guide To Rapid Fat-Loss, Incredible Sex And Becoming Superhuman is exercise and fitness book by Tim Ferriss, published in 2010.

The 4-Hour Body is that the results of a fanatical quest, spanning quite a decade, to hack the physical body. It contains the collective wisdom of many elite athletes, dozens of MDs, and thousands of hours of jaw-dropping personal experimentation. From Olympic training centers to black-market laboratories, from Silicon Valley to South Africa, Tim Ferriss, the #1 ny Times bestselling author of The 4-Hour Workweek, fixated on one life-changing question.