The First 20 Minutes: Surprising Science Reveals How We Can: Exercise Better, Train Smarter, Live Longer by Gretchen Reynolds is a very enjoyable read. She writes the “Phys Ed” column for the New York Times, so this book is very conversational and easy to follow. She makes that point that commonly accepted beliefs about health issues, such as the practice of applying ice after a hard workout. Recent studies have demonstration that icing and even massage provides no significant reduction in soreness.

Some news is very encouraging. Just 20 minutes of intense exercise will give us our maximum physical benefits. There are some cases where only 6 minutes are needed. The greatest benefits are gained by those who do no exercise at all an then begin exercising. This seems to agree with a post by Nilofer Merchant  in the Harvard Business Review Blog Network. She claims sitting is the smoking of our generation.Sitting down for a significant portion of the day can negate the benefits derived from some exercise.

Some results are surprising, such as that chocolate milk is better that Gatorade for sports recovery. I highly recommend this book.
The First 20 Minutes: Surprising Science Reveals How We Can: Exercise Better, Train Smarter, Live Longer