Pounding the body—muscles, tendons, ligaments and nervous system—with bone-crushing weights for multiple sets has produced a training evolution of sorts. It seems almost everyone is working each target muscle only once a week. Very convenient—but that can make for sluggish gains. Why? Muscles and the nervous system recover at different rates. So muscle recovery may occur in five days while the nervous system takes seven. That two-day gap can result in muscle atrophy, or shrinkage—possibly even back to square one (unless you're taking steroids).
Training body parts only once a week doesn't translate to the 4X mass method because it's a moderate-weight, high-fatigue hypertrophy trigger—there's less overall stress and muscles and the nervous system recover at almost the same rate—and relatively quickly.
For the uninitiated, 4X is taking a weight with which you can get 15 reps, but you only do 10; rest 35 seconds, then do it again. On set four, you go all out. If you get 10, add weight to the exercise at your next workout. That takes about five minutes per exercise...
To repeat, the weight is moderate. That means there is very little joint trauma, the nervous system is NOT stressed to within an inch of its life and cortisol output is minimal (cortisol is a stress hormone that can cannibalize muscle tissue). In other words, you will recover much more quickly with 4X training—and that can equate to bigger, faster muscle gaining if you do it correctly.
If you use 4X exclusively for all muscle groups, you should train them more frequently. Say you're using 3-exercise Positions of Flexion for each body part and a 3X or 4X sequence on each exercise. Most trainees make amazing size gains with that direct full-range attack twice a week for most body parts. Once again, your nervous system, joint structures and endocrine system aren't beaten to a pulp, so you're ready to roll after only a couple of days, target muscles feeling bigger and fuller. For example, a POF lat routine would be...
Midrange: Pulldowns, 4 x 10
Stretch: Pullovers, 3 x 10
Contracted: Stiff-arm pulldowns, 3 x 10
That's 10 sets, but only the last one or two sets of each sequence is to failure—and, once again, the big key is that the poundages are moderate. The sequence is such that you optimally stress the force-generating myofibrils while you also expands the sarcoplasm, the energy fluid in the fibers—a double dose of growth.
What made me write this blog is that someone told me they weren't growing much with 4X. Most people rave about it, saying it produces visible muscle growth almost from the very first workout. Once I dug deeper with this individual, I found he was training each body part once a week. Sorry, not going to work with that split for most people due to the reasons above. (You can post questions at the X-Rep Facebook page.)
If you can handle going against convention, you can often build muscles to extraordinary new dimensions. Give 4X a try for serious size—just be sure to hit each muscle often enough to keep growth surging.
Stay tuned, train smart and be Built for Life.