The 4-Hour Body is the result of an obsessive quest, spanning more than a decade, to hack the human body using data science. 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 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. It s the wisdom Tim used to gain 34 pounds of muscle in 28 days, without steroids, and in four hours of total gym time. From the gym to the bedroom, it s all here, and it all works.