X-Rep Rap—Top to Bottom

Q: I know you say that the best place for X Reps is down near the turnaround, close to the bottom of an incline press, for instance, but on contracted-position exercises, like concentration curls and leg extensions, I feel X Reps more if I do them in the flexed position [at the top]. Is it okay to do X Reps in the flexed position, or am I wasting my time?

A: It depends on which mass-building characteristic you’re attacking. The turnaround, where you move from the negative to the positive, is the semistretch spot—the max-force point—so it makes sense to do X Reps there on big, midrange exercises like incline presses. Remember that compound, midrange moves—the “big” exercises—are done specifically for max-force fast-twitch activation, so when you move to the target muscle’s semistretch point at full-range exhaustion, it amplifies the force overload.

You use contracted-position exercises, like concentration curls or pushdowns, primarily to finish off a muscle with continuous tension and occlusion, or blood-flow blockage. That’s the goal for those exercises, as they’re best for building the endurance components, like capillary beds and mitochondria.

The flexed, or contracted, position is where the target muscle is weakest because the fibers are bunched up, unable to fire as effectively as when they’re elongated and properly aligned, as they are at the semistretch point. That bunching, or crowding, however, as occurs at the top of a concentration curl, is excellent for creating additional occlusion.

In other words, your intuition is right on the money from the standpoint of tension and occlusion. End-of-set X-Rep partials done in the contracted position appear to be best for triggering more occlusive growth. In the e-book The Ultimate Mass Workout, Jonathan Lawson and I tied the X Spot of each exercise to its Positions-of-Flexion designation. For example, we performed X Reps for curls, the midrange move, near the middle of the stroke; X Reps for incline curls, the stretch exercise, at the arm’s-extended, full-stretch position; and X Reps for concentration curls at the top, flexed position. Most of those X points felt right and eventually led us to X-Rep variations that improved our physiques considerably.

The year after our initial X-Rep experiment we developed a number of X-hybrid techniques. One of the best for contracted-position exercises, such as concentration curls, was the X Fade. It takes some pain tolerance, but you get the best of both worlds—occlusive growth stimulation and a bit more max-force fast-twitch activation. The only drawback, other than the hurt, is that you need a partner to help you get into the contracted position for a lot of exercises, like the top of leg extensions, when you reach exhaustion. One exercise that doesn’t require a partner is concentration curls because you have a free arm.

Here’s how to use the X Fade: When you can’t get another full rep, use your free arm to move the dumbbell up into the contracted position and flex your biceps for three to four short X-Rep partial pulses—squeeze hard, even if you have to use your free arm to help. Then lower the dumbbell to the X Spot—just before full extension—and do as many more X Reps as you can. (If your nervous system has short-circuited from the standard reps, you may need to help yourself with your free arm during bottom X Reps as well.)

The top-end X Reps further occlude the biceps, while the bottom X Reps allow you to blast out the last bit of force from the fast-twitch fibers. That’s efficiency of effort and a reason Jonathan and I added almost 10 more pounds of new muscle during the year after we introduced X Reps—a fairly amazing feat for seasoned drug-free trainees.

Q: I’ve watched a number of pro-bodybuilder training videos, and none of those huge guys uses slow reps, not even on isolation exercises. I have all of your e-books, and you often suggest using a slower rep speed for contracted-position exercises to better feel the muscle. If that works, why don’t the pros ever use slower reps?

A: An interesting research study was just released that showed using lighter weights with a three-seconds-up/three-seconds-down cadence produced much more growth hormone and testosterone than standard one-second-up/one-second-down sets. The longer tension time was the kicker.

Bodybuilders know that they get much faster muscle increases when those key anabolic hormones are elevated. So how do pros grow without doing slower reps? They get supplemental GH and testosterone from their drug regimens. They don’t need to focus on getting a hormonal uptick from their workouts.

If you’re drug-free, however, it’s one more growth trigger you need to attack in your workouts. In other words, you should tailor some of your sets to stimulate anabolic-hormone effects. Here are a few ways…

1) Lighter weight/slower reps. As in the study, use a weight that will enable you to do at least eight reps with a three-up/three-down cadence—around 50 seconds of tension time. It works best on your contracted-position exercises (isolation moves, like leg extensions and concentration curls).

2) Lighter weight/higher reps. Use a standard cadence—1.5 seconds up/1.5 seconds down—but do 12 to 15 reps so you get close to 50 seconds of tension time. Once again, this works best on your contracted-position exercises.

3) Drop sets. Use a standard rep cadence, do a set with a weight that causes muscular exhaustion at around nine reps, reduce the weight by 20 to 30 percent, then immediately crank out as many reps as you can get—usually around six. That gives you the benefit of a long tension time, but by moving to exhaustion twice, you can hit more fast-twitch fibers. Drop sets work well on contracted-position exercises, but the technique can work for midrange, or compound, moves as well.

4) Supersets or tri-sets. Do two or three exercises back to back. For example, do a set of stiff-arm pulldowns (contracted-position lat exercise) followed immediately by a set of dumbbell pullovers (stretch-position lat exercise). For a tri-set you’d add a third lat exercise—you could start with pulldowns, for example, which gives you work in all three positions of flexion—midrange, contracted and stretch. That has a lot of the same benefits as a drop set, but because you use different exercises, you get a different fiber-recruitment pattern on each. 

Any of those four techniques will ignite muscle burn, which increases growth hormone release. Not only does GH amplify other anabolic hormones like testosterone, but it’s a potent fat burner as well.