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Density Isolation for Mass Stimulation

We’ve had great reports from bodybuilders using the Phase 1 Size Surge program merged with high-rep-set-first MMX. Using a 20-to-25-rep set first to failure has been shown to pre-fatigue slow-twitch endurance fibers so more fast-twitch fibers fire on your heavier sets after…

That high-rep set also triggers mass stimulation in the slow-twitch fibers, which have been shown to have more size potential than previously believed. 

Keep in mind that the Brazilian study on slow-twitch pre-fatigue for better mass-building effects used a short rest between the first high-rep set and the second heavier lower-rep one. That better initiates the Size Principle of muscle-fiber recruitment…

That Size Principle states that during a set, the majority of the fibers that fire first on the easier reps are slow-twitch, gradually transitioning to fast-twitch as the reps get more difficult.

So you must keep that short-rest rule in mind on one-leg or one-arm movements, like one-leg calf raises or concentration curls.

Example of Density Isolation for Mass Stimulation

What we’re saying is that when using the MMX method, you should do ALL sets for one arm first. For example, train your non-dominant arm first–for most people that is left…

Set 1: 20-25 reps to failure
Rest 30 seconds and grab a heavier dumbbell…

Set 2: 7-9 reps to failure
Rest 10 seconds, then…

Set 3: 4-5 reps to failure

Now you can rest for a minute or more, then repeat all of the above for your right arm. Again, that’s important because if you alternated arms, your left arm gets too much rest while you’re doing 20 reps for your right.

That’s important for all uni-lateral exercises like one-arm cable laterals, concentration curls, one-leg calf raises, one-arm DB rows, etc. Do all sets for one side first because…

It maintains critical density isolation for the most mass stimulation.

For more on MMX high-low to grow method and many innovative, quick size routines, see the MMX Fast Mega-Mass Workouts e-book.

SIZE SURGE: For variations as well as the complete original program Jonathan used to pack on 20 pounds of muscle in 10 weeks, grab a copy of The X-traordinary Size Surge Workout 2.0–a perfect hyper-growth routine. 

Till next time, train hard–and smart–for BIG results.

–Steve Holman and Jonathan Lawson
www.X-Rep.com

Filed Under: X Files

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