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Jurassic Spark: X-Rep Partials

Q: I discovered your mass-training concepts in IRON MAN and saw that drug-free bodybuilder Mike Semanoff had gotten great gains using X Reps. I worked them into my program, but I wasn’t sure if I did them right. I tried them at the end of my fourth set of presses and a few other exercises. When I got to failure, I did intervals of about 10-inch reps, as many as I could—usually three to five. Is that correct? Do you recommend doing X Reps at the end of all sets? I did feel unique muscle stimulation with them, like more fibers firing. Is that the reason X Reps work?

A: It sounds as if you have the right idea concerning proper X-Rep performance, although different exercises have different optimal ranges, or X Spots, in which you should perform the end-of-set partial reps.

On incline presses, for example, when you can’t possibly get any more full reps, you move the bar down to a few inches off your chest and drive up to just below the halfway mark; immediately lower to just off your chest and drive up again. Do as many of those low-end X-Rep partials as possible. They should feel like controlled explosive quarter reps.

By hitting that range, you’re extending the set at the point at which the target muscle is semistretched. Research shows that when a muscle is somewhat stretched, it can produce the most force and fiber activation and, therefore, optimal, growth stimulation. Because the target muscle still has strength in that range, you can get bigger size-building effects by extending the set there.

One of the main reasons X Reps work is the size principle of muscle-fiber recruitment. It states that on the first few reps of a set you use mostly the low-threshold motor units, on the middle reps of the set you bring in the medium-threshold motor units, and then on the hardest reps at the end you bring in the high-threshold motor units, which activate the key fast-twitch growth fibers. Adding X Reps after full-range exhaustion brings in even more of those hard-to-reach growth fibers, which helps you trigger bigger gains.
In addition, by extending a set with X Reps, you produce more muscle burn, which can increase growth hormone and testosterone release. In other words, you create a more anabolic hormone profile.

The X-Rep technique is a simple yet powerful mass builder, but don’t get carried away with it. I recommend performing X Reps on only the last work set for the big exercises—chins, presses, rows, etc. Always begin X Reps at the point at which the target muscle is semistretched. We mentioned doing them near the bottom of an incline press. Another example is near the bottom of a chinup. Start X Reps at the point right before your arms are fully extended, pulsing up to just below the halfway point before lowering again for another X Rep. Do as many low-end partials as possible.

On isolation moves, like leg extensions, leg curls and concentration curls, you can do X Reps near the bottom, where the target muscle is semi­stretched, or at the top, flexed position, a.k.a. the Flex-X technique. Top-end-squeezes help force more occlusion, or blood-flow blockage, which is a key to the size-building power of contracted-position exercises. X Reps performed near the bottom, where the target muscle is semi­stretched, are more for maximum fiber recruitment, although that somewhat helps occlusion in the muscle as well. A good strategy for continuous-tension isolation exercises is to perform semistretch-point X Reps on the first work set and the Flex-X technique on the second.

Mike Semanoff is an excellent drug-free bodybuilder who experimented with X Reps during a mass-building phase:

“I gained 20 pounds of muscle in two months. I’ve been training for a long time, so I knew that I had to provide my muscles with a totally unique stimulus to really kick-start growth. I found my answer when I started reading about X Reps. I was very intrigued. The whole concept of attacking the semistretched point of the muscle really opened up a whole new world of training potential. Once I got the hang of X Reps, I started adding poundage fast. Like clockwork the gains just keep coming. In fact, I won the heavyweight division at the Mr. Utah, and I took the overall at the Northwest Regional Natural Bodybuilding Championships.”

That was a few years ago, right after the original X-Rep e-book, The Ultimate Mass Workout, was released. For more information, look for X-Rep articles and Q&As at www.X-Rep.com. Warning: X Reps aren’t easy, but they’re a simple, exciting technique that can pack mass onto your physique. Just don’t abuse them.

Q: On my decline-bench presses—midrange position for chest—I got 10 reps on my first work set and eight on the second. I tried to do X-Rep partials at the end of the second set, pulsing below the midpoint, but I was too weak. I didn’t have any strength left to do X Reps. Is there something I’m doing wrong? Why am I weak at that point? Also, on some exercises I fail at 10 reps on the first set and then can barely do six reps on the second. Is that normal?

A: X Reps are difficult for different people on different exercises. It depends on individual neuromuscular efficiency in each target muscle. You may have that type of weakness in your pecs or one of the synergist muscles—for example, triceps or front delts on pressing moves.

If you can’t pulse with X Reps, do a single static hold at the X Spot for as long as possible—six to 10 seconds. That’s the next best thing.

Is a significant rep differential on set two normal? It can be. Once again, it depends on the neuromuscular efficiency and fiber makeup of the particular muscle or muscles you’re training. On some exercises your reps may go 10, 6; on others they may go 10, 9. Some people get more reps on their second set than the first.

For example, Jonathan, my training partner, sometimes gets eight reps on his first work set and then 10 on his second on some exercises—probably because his fast-twitch-fiber-oriented muscles need that first work set as additional warmup and nervous system priming to fire properly. When that happens, he usually does a third work set for growth-fiber-activation insurance.

You’ll get the best results if you simply do as many reps as you can on each work set, with X Reps or a static hold on the last set only. If the drop on the second set is too severe, you may want to reduce the weight to stay in the hypertrophic zone, which is nine to 12 reps—although if you get only, say, seven but can do enough X Reps, you’ll extend the tension time to more than 25 seconds, which is enough to reach that hypertrophic zone.

Q: I’m using the Ultimate Fat-to-Muscle Workout [from the e-book of the same name] four days per week, and I’m sore after every workout. Is that good? Does it mean I’m growing? My muscles feel and even look bigger. Can the program really work that fast?

A: The reason a sore muscle feels bigger is because you’re more aware of it—when you move and you get that sensation of pain—and also because it probably is actually bigger.

When a muscle is damaged, as occurs with the negative-accentuated sets in the Ultimate Fat-to-Muscle Workout, inflammation develops. That draws fluid to the tissue to accelerate repair, so it can actually look larger than usual—like you’re pumped up—for a few days.

The instant size increase will subside somewhat before you train that specific muscle again, but in a perfect scenario some of the size will remain due to supercompensation, and you’ll get somewhat bigger—and leaner—after every workout.

How does soreness equal more leanness? Scientists now recognize that muscle soreness equates to fat burning because of the same phenomenon that creates the instant size surge you’ve experienced—muscle damage. Muscle trauma requires energy to repair it, and the metabolic uptick is fueled by bodyfat. How great is that?

So should you strive for that familiar postworkout pain? While there are no studies that correlate muscle soreness with growth, it makes sense that damaging the muscle enough to make it somewhat sore would force it to rebuild bigger and stronger to prevent future damage—if you let it recover completely before you train it again.

While mild soreness is good, severe soreness is not so good, as it indicates so much damage that the body may not be able to repair it before your next workout. Research on pure-negative training, which we discuss in the e-book, verifies that. Here’s a passage from the e-book that explains:

“A study performed in the 1990s by Frank G. Shellock, Ph.D., showed the extensive damage pure negatives can do. Subjects performed one set of positive-only curls with one arm and negative-only curls with the other, both sets to failure. Results...
“The positive-work-only biceps showed no damage, while the negative-work-only biceps showed damage that peaked five days after exercise. Soreness finally dissipated by the ninth day, but some subjects didn’t regain all of their strength in the pure-negative-trained biceps for six weeks!”

That last statement is important. It indicates that pure-negative work damaged the muscle so much that it didn’t recover for six weeks in some subjects—and that was after only one pure-negative set to failure. Yes, most of the test subjects were untrained individuals; nevertheless, you can see how extremely traumatic pure-negative work can be.

We believe that’s true even for experienced bodybuilders. That’s why we prefer the less-severe negative-accentuated version most of the time—lift the weight in 1.5 seconds, then take six seconds to lower. Start with one seven-rep negative-accentuated set on a multijoint exercise for each body­part, and you’ll start seeing and feeling great things in both muscle and rippedness. With the right amount of muscle trauma and postworkout soreness, you can be sure that you’re getting a real fat-to-muscle effect that can transform your physique quickly.

Editor’s note: Steve Holman is the author of many bodybuilding best-sellers and the creator of Positions-of-Flexion muscle training. Visit www.X-Rep.com for information on X-Rep and 3D POF methods and e-books. IM

About Steve Holman

Steve Holman has been training for over 35 years, since he was 15, and has been IRON MAN Magazine's Editor in Chief for more than 20 years. He has written more than 20 books on bodybuilding, weight training, nutrition, and his popular "Train, Eat, Grow" series, which he writes with his training partner Jonathan Lawson, appears monthly in Iron Man magazine. Steve's latest e-books are available at www.X-Rep.com and www.X-traordinaryWorkouts.com

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