2.5
(What I have to say only concerns the Danish edition, because I have not seen the English, but I reckon that they're not that different.)
I'll start by saying that this is a okay introduction to running, but the book cannot stand on it's on. If you want to take running to the next level and do seriously, I recommend picking at least one more book up about running, preferably one that a bit more, well, thicker and reliable.
The reason why I only give this book 2.5 stars, because the author(s?) cannot figure out if they want to appeal to the general public, people who has not exercised in years or serious runner. They go from running in 10 minutes to running 10 kilometres on the same page. This can be because there were more than one author or because in their eager to appeal to everyone, they have tried to something that they just couldn't do within a book with a size smaller than an A5 page and only a hundred of pages.
This book also cannot decide if it's readers have been exercising forever or never before, they continue to use bigger words than necessary. The point of the book should be to make running and information about running accessible easier and using technical terms that a completely unnecessary does not help anyone.
Also, the books also has a lot of pictures of people running - but only one picture of an old person and one picture of a group of people have average body build. The rest are of fit and more or less beautiful men and women. That also defeats the purpose of making running look accessible to people who tends not to exercise.
That being said, it can still enlighten you about the basic information about varies things when it comes to running.