Moderate Weights, High Fatigue, Bigger Muscles

My primary goal at every workout used to be to move more weight. I equated getting stronger with getting bigger—but it never worked very well. Why? To get a muscle as big as possible, you have to build both “sides” of the key growth fibers. Like most bodybuilders, my workouts were focusing on only one facet of growth. I was leaving a lot of muscle size on the table. That’s because heavy training trains mostly the myofibrils.

The myofibrils are the actin and myosin strands that grab onto and pull across one another to generate force. Those strands are inside muscle fibers, and you can build them with heavy weights, lower reps and longer rests.

The sarcoplasm is the “energy” fluid that fills each fiber. It’s composed of glycogen (from carbs), mitochondria, potassium, calcium, creatine and noncontractile proteins. You force expansion of this fluid, along with the size of your muscles, with high-fatigue methods.

I’ve mentioned Doug Brignole, Mr. America and Mr. Universe, in a previous blog. After getting some amazing gains, he is now a proponent of the moderate-weight, high-fatigue method. Here’s what he discovered: “The growth potential of the sarcoplasm seems to be much greater than the growth potential of the myofibrils. In my estimation, sarcoplasmic growth may have as much as twice the growth potential as myofibril growth.”

That’s especially true for hardgainer types who tend to get almost zero growth from heavy training. If they want that coveted bodybuilder look, they need to focus on building sarcoplasmic size, which is where they have the most growth potential.

To help you visually grasp how a muscle fiber gets larger, here are a couple of illustrations…

Most bodybuilders’ training produces a muscle fiber similar to Fig. 2 (below left). Heavy weights tend to build the myofibrils without much sarcoplasmic size.

To create the fullest fiber possible, Fig. 3 (below right), you must use high-fatigue methods, such as higher reps, the 4X mass method or X-centric sets.

Here’s the 4X drill: Take a weight with which you can get 15 reps, but only do 10; rest 30 to 40 seconds, then do 10 more—and so on for four sets. On the last set go all out. If you get 10 reps, either add weight at your next workout or go for 4×11.

The short rests will cause cumulative fatigue, which is a key to new sarcoplasmic size.

An X-centric, or negative-accentuated, set relies on extended tension time for sarcoplasmic-size stimulation. Here you use a one-second positive and a six-second negative on every rep, reaching failure around rep 7. That will hit the target muscle with 50 seconds of tension time, about double what most bodybuilders get per set.

Also, both the 4X and X-centric methods provide excellent myofibrillar-growth stimulation as well. With 4X, the weight is heavy enough to stress the myofibrils, plus there is a cumulative effect from so many reps (40), the last of which are all out. With X-centric sets you lower a moderate weight slowly, which produces extra microtrauma in the myofibrils, leading to supercompensation, or hypertrophy. So with both you get a double dose of muscle growth.

The exciting news is that you can get extreme muscle size without grinding your joints into dust. In fact, moderate-weight/high-fatigue training can get your muscles bigger and fuller than you thought possible.

I’ll have more on this in future blogs, including the hormonal implications of this controversial muscle-building style (more growth hormone and testosterone; less muscle eating cortisol—all of which leads to a more massive you).

Stay tuned, train smart and be Built For Life.