I'm sure he has more exhaustive logs that support his claims but the quote above (the same story was in Wired a few weeks back) isn't detailed enough to prove t

I'm sure he has more exhaustive logs that support his claims but the quote above (the same story was in Wired a few weeks back) isn't detailed enough to prove that Tim gained 8.5 pounds of muscle per week. I was unfamiliar with hydrostatic weighing so I looked it up. Hydrostatic weighing appears to measure water displacement to figure out the body's density and hence fat to muscle composition. The density of muscle is 1.06 g/ml and fat is 0.92 g/ml. [1] A gain of 30 pounds of water (1.0 g/ml) would show up as roughly equal gains in fat and muscle since water's density is about at the midpoint between fat and muscle. Ferriss's claim is +34 pounds of muscle and -3 pounds of fat. I'm certain Ferriss gained lots of muscle in his four-week trial. His methodology isn't all that different from Gallon Of Milk A Day (GOMAD) plus the Starting Strength workout plan, both of which I've personally used to some success. That said, the freely available quotes don't give all of the necessary information. If you happen to buy the book, please share with us. http://answers.google.com/answers/threadview/id/576481.html http://answers.google.com/answers/threadview/id/576481.html