Yes, although I have dumbbells at home, I only practice unarmed for convenience now. Prisoner's Fitness teaches people how to practice muscles by hand. The movement difficulty is divided into six grades, which are suitable for exercisers of different degrees. This is not a book that teaches you to develop "lovely muscles", but a book that teaches you to develop available strength, extreme strength and survival strength. Because the link can be easily deleted, the landlord Baidu knows that it can be found by searching for prisoner fitness.