The 4-Hour Body is the result of an obsessive quest, spanning more than a decade, to hack the human body. It contains the collective wisdom of hundreds of 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 New York Times bestselling author of The 4-Hour Workweek, fixated on one life-changing question:

For all things physical, what are the tiniest changes that produce the biggest results?

Thousands of tests later, this book contains the answers for both men and women.