
“Besides,” Mike explained, “it’s very difficult to accurately assess your genetic potential. He worried that the notion that you have to have good genetics to achieve a championship physique had actually served to destroy the motivation of certain bodybuilders. While genetic characteristics were important, Mike believed that they had been overemphasized. In later years, however, he confided that he had reservations about making such a strong case for genetics. Without question genetics played a huge role in providing the foundation for the muscular mass that Mike built, as he was the first to admit. Upon hearing that, I quickly realized how much deceit was being practiced in the bodybuilding world, where champions whose arms were obviously far less substantial than Mike’s would loudly proclaim measurements of 21 inches or, in some instances that stretched credibility to the breaking point, 22 inches.

“Pumped, they probably are, John,” he replied, “but measured cold, which is how you should measure your arms, they never stretched the tape beyond 18 1/2.” “But they look well over 20 inches!” I exclaimed. I once asked Mike what his arms had taped at their largest, and his answer startled me: “About 18 1/2 inches.” I was incredulous. When Mike Mentzer was asked how big they were at one of his seminars, he responded with characteristic wryness, “Very big.”

Reports varied as to the actual size of his arms. His triceps, in particular, when viewed from behind, reminded one of two large watermelons hanging out of a T-shirt. He stood only 5’8′ yet packed 215 pounds of rock-solid muscle on his frame.

It was the essential basic Heavy Duty routine consisting of four to five sets per bodypart and broken into two workouts.
