I bought this book for my wife as a present - although she wasn't that pleased to receive it. I feel that she may be a little over-sensitve as some women are towards their weight, but seriously she is a mighty walrus of a woman - a genuine behemoth. That is fine by me - she is good with our kids, knows how to provide an excellent and hearty meal, and she never looks at another man - unless, one presumes, she is peckish. I on the otherhand am a reasonably fit and trim 11 and a half stone - a keen cyclist and competent long-distance runner.
To be fair, she was more keen to try this than repeatedly eat vegetables or walk anywhere, so I thought my luck was in. Usually, such activites are reserved for Christmas or when she has had one too many G & Ts. However, after realising that a "quickie" would burn off as many calories as are in a fun-sized Mars bar she set to work what could only be described as "with some vigour".
Sadly, it seemed to make no difference to her weight, and all I ended up with was a broken bed and a punctured lung for all my trouble.
It may work better for you but don't expect it to improve your life markedly. In fact it only served to make mine worse.