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STX for Multi-Fiber Hypertrophy and Extreme Mass

Q: Using a high-rep set to failure to fatigue the slow-twitch fibers prior to heavy sets for extreme mass makes sense. My heavy sets have the feeling of deeper activation, and I also like the fact the the slow twitch ones get growth stimulation too, along with more fast-twitch. My problem is that I HATE high reps. Even doing just one set of 20 to 30, I’m sure I’m stopping way early because it’s boring, not to mention it hurts. Is there another way?

A: Yes, there is absolutely another way–and to understand why it works, you need to grasp the Size Principle of Muscle Fiber Recruitment. That basically says that in any set, the earlier reps fire a majority of slow-twitch fibers. And as the reps get harder, more and more fast-twitch fibers are brought into play. At failure, the majority of fibers firing are fast-twitch.

So instead of one high-rep set, what if you did a few 10-to-12-rep sets, but NOT to failure and with short rests between? Those sub-failure sets close together would fatigue mostly slow-twitch fibers just like one all-out high-rep set. The hard set or sets to failure after would still activate more fast-twtich fibers because of the slow-twitch exhaustion (STX), which was shown in a recent Brazilian study published in the European Journal of Applied Physiology.

But way before that was proven, that’s precisely how legendary bodybuilder Danny Padilla built mass. He was known for his classic, no-flaws physique–at only 5’2″, and his nickname was “the Giant Killer” because his perfect mass-symmetry combo allowed him to beat bodybuilders who were much taller and larger than he was. You can see why his physique is “legendary” in these pics…

PadillaGymBeach

The method that helped him place in the top five of many pro contests back in the ’80s was 5 sets of 12–same weight on every set, with short rests between sets–never more than a minute. When he was able to do 12 on all five sets, he would up the weight a bit. The first sets were fairly easy; the last few were brutally hard…

So the first few sets were exhausting primarily slow-twitch fibers–and getting them to grow. The last two or three sets were very difficult and had him activating primarily fast-twitch growth fibers. A very efficient way to train and get a double-barreled growth effect–extreme hypertrophy in multiple fiber types.

Familiar Extreme Mass Method

If his method sounds familiar, it’s because we based our 4X Mass Method on Danny’s training, which was an off-shoot of Vince Gironda’s Density Training–moderate poundages, short rests between sets. It’s relatively safe size building based on how muscle fibers work…

The first “easy” sets pre-fatigue the slow-twitch fibers, gradually bringing in the high-growth fast-twitch fibers on the last tough sets…

The bonus of this style of training is you don’t have to use joint-crushing poundages–the weights for 4×10, 4×12 or 5×12 are moderate due to the fatigue/exhaustion factor created by short rests between sets.

Try 4X for multi-muscle-fiber growth success–no high-rep sets or joint stress.

> The 4X Mass Workout 2.0 is available HERE.

4X Mass Workout small cover

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

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

Filed Under: X Files Tagged With: 4X, danny padilla, fast-twitch, slow-twitch

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