>>76316353
What became known as High Intensity Training, of which Mentzer had his own brand called "Heavy Duty," was introduced by Arthur Jones in the 70's in response to the high volume nonsense which popped up in magazines that only works if you take a lot of drugs and that even the bodybuilders who claimed to do that never did with few exceptions. Jones' observation was that Intensity of Effort and progressive overload were what was most important for training.
Jones prescribed it in a 3 day per week full body routine with 1-2 sets per muscle group depending on how you count with pre-exhaust supersets to address proportional problems in compounds in order to train targeted muscle groups. i.e. the standard Colorado routine that Jones did with Casey Viator in the Colorado experiment had typical supersets that Mentzer continued to write down like the pec fly into machine press and leg extension into leg press supersets.
Mentzer in particular did a 2-way split twice per week with similar volumes to the Colorado routine. According to Roger Schwab, the head judge at the time, when Mike was training for the 1979 Mr. Olympia and Roger watched him, he was doing that Colorado routine three days per week.
Viator, Mike Mentzer, and his Brother often worked out together and did the same routine. Though Casey and his Brother did a lot of heavy partials and Mike had to stop doing those because they started to hurt his joints.
The stuff that came later like the 4-7 rest days between each workout with only one pre-exhaust superset came in the late 90's when he was mostly training gen-pop and only a handful of advanced trainees.
