Actually HIIT was designed for fat loss, along with superior cardio benefits, with keeping (or even increasing slight muscle mass) rather than a prime goal on gaining max muscle mass. With training periods twice or three times a 7 day week (sometimes a training week can be sectioned to a 9 day training week...even longer extensions can be done). Never want to do any cardio between workout days on this style system. Too much of a good thing can lead to failure on many an over ambitious BB'er. A 8 weeks program, to the extreme 12 weeks, is usually the limit on such intense style programs.
If you don't mind, could you give a general outline of your individual workout days. And would you be training with weights/machines only? Is BB'ing and advanced muscle mass the main purpose here? Or getting surprisingly ripped. Like if you have 17" guns, and have them fall (with HIIT, etc) to 16 1/2..which will look that more muscular and impressive without any extra fat on those guns.
Athletes use interval (HIT, HIIT, Tabata and other versions) protocols to adjusted to personal needs & goals. All are great ways to increase the Vo2 max (fat burning, higher level of metabolism/upping testosterone levels also) for the average trainee. In either case, the stamina (strength+ endurance) becomes sky high. Tabata uses the 2:1 (20 seconds max effort)...... 1 (10 seconds rest/pause between efforts). HIIT, and other version, may use a different work/rest pattern. All work well, depending on your training ambitions.
Good Luck.
