“Start thinking NOT in terms of how much you can lift, rather how much you can lower!”With those prescient words, genius Nautilus inventor Arthur Jones unlocked the key to the great potential of progressive exercise. Forty years later, that promise has been realized with the advent of X-Force, the “final breakthrough” in negative accentuates training. We all possess three levels of strength: concentric or positive (lifting), static (holding) and eccentric or negative (lowering.) Negative strength is approximately 40% greater than positive strength, and static strength is midway in between.

According to a study published in the British Journal of Sports Medicine in 2009, “Eccentric (negative) training performed at a high intensity was shown to be more effective in promoting increases in muscle girth.  Eccentric training showed a trend toward increased muscle cross-sectional area measured with MRI. The superiority of eccentric training to increase muscle strength and mass appears to be related to the higher loads developed during negative contractions.” (Roig. M. et al, Br) Sports Med. 43: 556-568:2009.

According to Ellington Darden, Ph.D., “When the strain on the muscle is focused and intense from multiple repetitions with controlled negatives, the movement mechanisms at the microscopic cellular-level actin protein filaments and myosin movement molecules pull apart and tear slightly.  ALL growth from strength training MUST be stimulated by preparing and slightly tearing at least some of the involved actin and myosin tissues.  That slight tearing is the catalyst for repair and overcompensation.”

Science seems to indicate that negative work is possibly the most significant phase of the repetition.  The question is, as it has been since Arthur Jones emphasized the negative, “what’s the best way to apply that information to the workout?” After all, with a barbell or conventional machine even by “accentuating” the lowering (negative), you can only lower what you can lift, which is less than desirable considering that the trainee is 40% stronger during the lowering phase of the rep. Using a barbell necessitated the use of spotters, who would have to coordinate a handoff of the heavier resistance to the trainee, who would then lower the resistance. A faulty handoff presented problems and potential injuries.

Due to this and many other problems, the concept of negative training and its great promise was lost – until now! X-Force equipment designed by Mats Thulin of Sweden and his X-Force team of engineers has taken a giant step towards refining and perfecting the negative accentuated training system by solving those problems.

According to Dr. Darden, the approach involves a “tilting” weight stack powered by an electric servo motor.  As the user begins the lifting stroke, the weight stack tilts to a 45-degree angle, instantly reducing the selected resistance by approximately 29%.  At the apex of the positive stroke, the tilted weight stack returns to vertical, and then the user lowers 100% of the selected resistance.

For example, on the X-Force Pec Seated Press machine, you select 140 pounds. As you start the positive phase, lifting the resistance, you are moving 100 pounds (29% less than 140).  Quickly, in 0.5 of a second, the weight stack goes back to the vertical position as you do a controlled negative rep with 140 pounds (40% more than 100 pounds.) Ideally, the set is completed in 5-8 reps.

So what are the practical applications of X-Force training? Main Line Health and Fitness has been utilizing this equipment since January 2012.  To say that the results that we have stimulated are staggering would be an understatement. In my own case, at 70 years old, I have found these workouts to be the MOST productive of my life. At an age where most trainees are simply trying to maintain their current levels of strength and halt the inevitable – ravages of sarcopenia and the degenerative loss of muscle mass, I have stimulated lean muscular gains as fast or faster – and certainly more efficiently – than any previous type of training. I might add that I have been training for 50+ years, having at one time established Pennsylvania state   Olympic and Powerlifting records in my weight class. My bodyweight is up and my body fat is down, significantly. THIS is a game-changer and NOT supposed to occur at my age.  Younger trainees are seeing far better results, both men AND women. They are becoming leaner and stronger in a fraction of the time! Hyperbole? Hardly!  The results that X-Force can stimulate must be experienced to be understood.

What is the SECRET behind the result-stimulating effect of X-Force machines?  According to Ellington Darden, Ph.D., who has done extensive research with this equipment in Gainesville, Florida, “X-Force, with its tilting weight stack that overloads the negative stroke with 40% more resistance, makes a deeper inroad (muscular fatigue within the set of an exercise) faster and more thoroughly than does normal training into an exerciser’s starting level of strength.”

Darden’s intense research has led him to groundbreaking conclusions regarding hormonal changes and negative training.

According to Darden, “Apparently, the deep inroad into starting strength stimulated by X-Force stimulates the production of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) that not only lead to muscle hypertrophy, but can also oxidize fat-cell content at a faster-than-naormal rate. Releasing fat rapidly is probably assisted by another related hormone’s anabolic influence on both muscle and fat. That hormone is insulin.

“In other words, with negative accentuated X-Force training, the deeper inroad diminishes insulin sensitivity among fat cells and they begin to shrink. As insulin sensitivity in the muscle elevates, glucose and nutrients are directed preferentially into muscle cells and they expand.”

At Main Line Health and Fitness, we have found that ONE 30 minute X-Force session per week is all that is needed and in most instances all that can be tolerated. Very efficient it is. Very easy, it is NOT. Since we at MLH&F have most likely had the most experience worldwide with X-Force, we have somewhat of an understanding about what we have found to be proper protocol.  Our evidence is empirical, and we have not attempted scientific research.  However, Dr. Darden’s new book THE BODYFAT BREAKTHROUGH explains his research into negative accentuated training and how it affects fat loss and lean muscular gain. It is valuable reading for anyone interested in this “revolutionary get-back-in-shape program.”

MLH&F is made up of nearly 70% women members and initially presented us a challenge in an attempt to enlist a significant number of women into the X-Force program.  In what should not have been surprising to us was the osteogenic effect of X-Force training.  Soon we were seeing bone mass as well as lean muscle mass increases. We always recognized that strengthening the function muscle would have an effect on the structural bone. Now, we were seeing the outcome on “t scores” firsthand.

In our opinion, X-Force training is paramount to realizing the great potential that is possible from medically sound progressive exercise. It seems, from our experience, to be the “next step” if not the final step itself.

The results stimulated by X-Force have simply yet definitely revolutionized training at our facility. I encourage you to try it. We would be happy to answer any questions about our programs and our use of X-Force.

Interested trainees can ask for Roger Schwab at X-Force Philadelphia, 215-372-9090.