Okay, so what is the first question you might have when looking at the title.... let me guess what the heck is 5:2 and Training? No, I am not psychic, I just had the exact same question when I read the title. The 5:2 concept is five days of regular eating and 2 days of fasting or very low calorie eating. The 5:2 diet however needs a workout component of 3 days to be effective according to the author Niclas Brunnegard.
The book is written to include the articles he cites at the end if you want to look further into where he got his information and how to follow the diet. For the low calorie or fasting portion he recommends 500 calories for women and 600 for men. That being said it does seem like a very low calorie amount, but he includes several recipes to accompany it and help you keep with the diet.
As for my personal opinion on the book I will say that it well written and cited but the whole logic behind it is not something that I feel comfortable with. That being said, I did not try it. I don't like the feeling of being hungry so this is not a diet that works for my personality, but if your good at fasting this may be for you.
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