"High-Intensity Training the Mike Mentzer Way" was Mentzer's final work. In it, he detailed the principles of high intensity weight training. Weight training, he insisted, had to be brief, infrequent, and intense, to attain the best results in the shortest amount of time. "Heavy Duty II" also espouses critical thinking. In this book, Mentzer shows why people need to use their reasoning ability to live happy, mature, adult lives, and he shows readers how to go about doing so. Bodybuilding was endorsed as only one potential component of an individual's existence, encouraging many other worthwhile pursuits throughout his books.