The Essentials of Surfing is a textbook for surfing. You can’t learn to surf by reading a book, but The Essentials of Surfing will give you the knowledge you need to be more confident about learning to surf, avoid conflicts with other surfers, and diminish your chances of becoming a productive member of society.
This sounds like a joke book you might give someone to insult their athletic abilities. But Fitness for Nerds is actually a sophisticated fitness guide for smart people. Fitness for nerds provides step by step details for a proven method that helps motivate nerds to be active and fit. It requires nerd skills, but not previous athletic experience.