What’s the Science Behind X3?

We designed the X3 system and program to help you leverage new scientific findings for the most effective strength-building workout. Get a glimpse into the science behind the product from peer-reviewed references and studies.

The Science Behind X3 and Why It Works

In 2015, Dr. Jaquish authored a research protocol for a London-based hospital to study human performance and bone. In that study, he discovered that individuals could create tremendous forces through the body when isolating the impact-ready range.1

Compared to the American College of Sports Medicine database, these forces were 7 times greater (Zone A below).2 After making this discovery, he realized that lifting weights was the worst way to trigger muscle growth.

John Jaquish performs an X3 press in zone A
Complete Muscle Fatigue with X3

In the words of Dr. Jaquish:

You’re seven times stronger than you think you are. This is because humans have vastly different strength capabilities at different ranges of motion. With variable resistance training, you can safely train with the proper forces for every range of motion.

Our team then designed a workout system to help people leverage these new scientific findings for the best strength training workout possible. The X3 bar unlocks your muscle-building potential while minimizing the risk of injury. It empowers you to work out without limitations and the risk of cumulative joint damage.

While using the prototype, Dr. Jaquish gained 30 pounds of muscle and lost body fat simultaneously. NOW, there is a FAR better way to achieve your fitness goals.

Dr. John Jaquish discovered humans are seven times stronger in impact-ready positions (your strongest range of motion) than in the joint-compromised weak range. This simple yet previously overlooked discovery explains why Weight Lifting is a Waste of Time, and is the subject of his book of the same title.

A man performs a deadlift with a barbell
The Barbell Deadlift Movement

Take the deadlift, for example. You begin the exercise in your weakest position, move through your medium range as you lift, and finish in your strongest range just before you have completed the lift. Choosing a weight for your weakest range limits the weight you can lift and wastes considerable strength potential across the range of motion.

The X3 Bar System: The Ultimate Strength Training Disruptor

X3 properly leverages variable resistance training to safely train with the proper forces for every range of motion: lower weight forces at the bottom and higher weight forces at the top of a movement than traditional weights. The weight changes as you move through each repetition and continues to challenge you – with an increasing force – that’s safe for you at any moment.

X3 Bar is the best way to work out, and we will make that case with additional peer-reviewed references from other studies in the following paragraphs. You will also see some articles at the bottom of the page, published in the popular press, extolling the advantages of variable resistance.

Variable resistance (such as X3) creates muscle gains faster than conventional training. We quote from a study on Cornell Student-Athletes:

Compared with C(control), improvement for E (elastic) was nearly three times greater for back squat (16.47 +/- 5.67 vs. 6.84 +/- 4.42 kg increase), two times greater for bench press (6.68 +/- 3.41 vs. 3.34 +/- 2.67 kg increase), and nearly three times greater for average power (68.55 +/- 84.35 vs. 23.66 +/- 40.56 watt increase).3

So, compared to regular weight training, variable resistance training led to greater gains in one-rep max and greater gains in average power for the time period tested. The benefits of training with variable resistance may be one of the most profound discoveries in the history of sports performance science.

You may notice that the elastic group in this study combined variable resistance training and resistance training. These athletes used bars and plates attached to elastic bands, so while the resistance varied, they always had to lift the bar/plate/other mechanical assembly.

Although the X3 Bar is light, we provide a similar experience since the product is comprises an olympic-style bar, and a plate. For this reason, we also advise using X3 with constant tension during exercises. Ensure the band always has tension for each exercise’s entire range of motion.

A resistance band bar with band attached
A X3 Bar with the 600+ LB X3 Elite Band. (full system not pictured)

When used this way, X3 Bar replicates the study conditions that led to increased muscle growth very effectively since that constant tension always provides a baseline level of resistance as there would be with a weighted barbell. Then, that resistance increases as one goes through the range of motion. After all, muscle tissue certainly can’t tell if a force is applied by an elastic band or gravity acting on an iron mass.

X3 for Effective Variable Resistance

Variable Resistance (such as X3) shows greater anabolic hormone responses over conventional weight lifting.4 Variable resistance increased serum Testosterone and Growth Hormone more than regular weight lifting.

X3 Makes (High Intensity) Variable Resistance Accessible: the X3 workout derives the variable resistance component from resistance bands. You may wonder, “Why not get just resistance bands?” With X3 Bar, you can double over a heavy-duty band to perform an exercise at over 600 lbs of force.

A man performs a heavy deadlift with variable resistance
The X3 Deadlift Exercise

As best we can tell, that’s impossible with the band twisting one’s ankles and applying all that torsion to one’s wrists. Not only is there a risk of injury, but the body reflexively limits muscle activation when this kind of discomfort exists in a protective process called neural inhibition.

With X3 Bar, you avoid these limitations, which lets you lift heavier and reduces the risk of joint damage. With X3, you gain a standard barbell interface, and you can perform the same lifts you would have with conventional weights, but now with the benefits of variable resistance.

Variable Resistance Versus Weights: Additional Studies

Another of the most compelling pieces of research on variable resistance (which showed more significant muscular gains in the variable resistance group compared to the conventional weight group) used elastic bands attached to bars and plates, not elastic bands in isolation.

We set out to closely replicate the experience in the scientific study to allow X3 users to train with greater force to trigger greater muscular gains.

No, you don’t have to be a “Student-Athlete” to use variable resistance (Obviously?): In talking with people about the Cornell Athlete Study, we encountered the baffling objection that “variable resistance training only offered so much improvement because the athletes were already so highly trained.”

That supposed principle of athletics, where it gets easier to improve once you are already highly trained, isn’t backed by data. Regardless, there is research on a middle-aged, sedentary population, where even low intensity elastic band training was found to be at least as effective as weight training.5

No, there are no secret benefits when attempting to train heavy in weak ranges of motion: Training with variable resistance also gives you more force where you can actually recruit muscle tissue. Again, people confronted us with the highly unexpected allegation that “the weakest range of motion is where you train the muscle,” this is untrue.

A graph showing human strength potential
Strength Output By Range of Motion

Look at research into muscle recruitment (potentiation) during maximum-effort bench press exercise. In the weakest range of motion, “the sticking point,” failure is not caused purely by mechanical disadvantage but rather by the fact that muscle recruitment drops sharply, as measured by electromyography.

As one study postulates, the sticking point in a weak range of motion occurs due to “diminishing potentiation of the contractile elements during the upward movement together with the limited activity of the pectoral and deltoid muscles”. 5

The researchers observed that in the weakest range of motion, under high loads, the exerciser cannot recruit nearly as much muscle tissue as they can elsewhere in the range of motion. This limitation is a protective feature of the nervous system, meant to prevent a person from injuring their joints by applying too much force to them while in an awkward position. Regardless, a brief reflection on this issue should tell us that if we cannot use the nervous system to obtain high levels of muscle tissue engagement during high-load events in a weak range of motion, muscle tissue is probably not getting much training benefit from that part of the exercise.