Amazon calculates a product’s star ratings using a machine learned model instead of a raw data average. The machine learned model takes into account factors including: the age of a review, helpfulness votes by customers and whether the reviews are from verified purchases.
Loved the book, having to refer back across different chapters to work out training program was a pain though.
Trained with heart rate monitor for first time & I was training to focused on intervals. I brought the book as I was running out of puff towards later stages of interval work outs & realised I was lacking endurance. I am preparing for for my first half marathon & will use program, which once put together seems very easy to follow