Forty-plus years ago, Arthur Jones published his seminal statement, Bulletin #1, examining and explaining the fundamentals of strength training. In chapter 37, Arthur thoroughly details the principle of “pre-exhaustion,” which, in his opinion, is a long first step in the direction of improving the results that are possible from weight training.

According to Jones, conventional compound exercises “involving the functions of two or more muscular structures, a point of failure (the inability to complete a repetition in proper form) is reached when the weakest involved muscles are no longer able to perform.” For example, in a barbell or machine bench press, the smaller muscles of the triceps fail long before the larger and stronger pectoral muscles have been worked as hard as necessary “for the production of best-possible results.”

However, if a set of arm crosses, a direct single-joint movement for the pectorals (and related deltoid structures) are IMMEDIATELY followed (less than 3 seconds) by the bench presses, the pectorals will be worked much harder than previously possible. Thus, the theory behind “pre-exhaustion” is to perform a single joint movement that isolates a muscular structure (as best as is possible), and then this exercise is IMMEDIATELY followed by a compound movement that involves several muscular structures, including the musculature involved in the first exercise.

According to Ellington Darden, Ph.D., pre-exhaustion stimulates “a very deep inroad, the depletion of momentary strength, repetition by repetition, from the set of an exercise.” Dr. Darden is convinced that growth of the involved muscular structures is closely linked to inroad.

Pre-exhaustion can be utilized in many combinations with many muscular structures. And although the pre-exhaustion principle did not originate with Arthur Jones, it was Arthur who best understood and explained the principle and put it into practice with his Nautilus “double-machines” in the early 1970s. Trainees who understood and incorporated pre-exhaustion into their routines stimulated results that many trainees could achieve in no other way.

Pre-exhaustion has always been the “staple” of our client’s workouts. We have stimulated far greater results from this principle than traditional “push-pull” routines, which as Jones pointed out, result in “failure” of smaller muscle groups before the targeted larger structures are thoroughly worked. However, after 40 years of hard workouts, we are now, in 2017, stimulating results far better than we ever have previously – FAR better than even Arthur Jones realized at the time! The tremendous potential of pre-exhaustion has now been fully realized with the introduction of X-FORCE equipment, which, in my opinion, is the foremost advancement in strength training since the Nautilus machines and the MedX Medical Spinal machines. The results stimulated at X-Force in Philadelphia plus the documented results of programs developed by Ellington Darden at the Gainesville Health and Fitness Center in Gainesville, indicate that X-FORCE is capable of stimulating results on a whole new level. Dr. Darden has precisely expressed that “the negative stroke with 40% more resistance makes a deeper inroad, faster and more thoroughly, than does normal training into an exerciser’s starting level of strength. THE DEEPER INROAD STIMULATES THE PRODUCTION OF GROWTH HORMONE (GH) AND INSULIN-LIKE GROWTH FACTOR THAT NOT ONLY LEAD TO MUSCLE HYPERTROPHY, BUT CAN ALSO OXIDIZE FAT-CELL CONTENT AT A FASTER THAN NORMAL RATE!” Darden is not alone in the realization that X-Force is an indispensible “game-changer.’ Science has also spoken. “Meta-analysis showed that when eccentric exercise was performed at higher intensities compared with concentric training, total strength and eccentric strength increased more significantly.”  Furthermore, “eccentric training performed at high intensities was shown to be more effective in promoting increases in muscle mass measured as muscle girth,” plus “increased muscle cross-sectional area as measured with MRI.” (1)

Beginning trainees are experiencing strength results quickly, efficiently and safely, increasing muscular mass while decreasing body fat levels. Even BETTER results are being stimulated by more experienced trainees. Proper intense work utilizing X-Force in conjunction with pre-exhaustion is enabling competitive athletes and strength trainees to reduce their workouts to ½ hour, once a week . Brief workouts with a higher intensity stimulated a response that most of these advanced trainees had NEVER before experienced. Strength, flexibility and cardio-respiratory efficiency are stimulated in one workout, once a week!

Women have also embraced X-Force. It has taken time and effort.  However, slowly but definitely, the age-old myths of “big muscles” and “aerobics only” are being replaced by “strong is the new beautiful” and  “train hard or go home.” Not only are women fully realizing the value of stronger muscles, a faster metabolism and a mental “toughness” that comes from looking at herself as “a strong woman,” but dexa scans are also revealing a reversal of osteopenia and/or osteoporosis, and there is “no looking back. Scientific research indicates that eccentric muscle training is more osteogenic than concentric training. (2)

The following workout has been utilized by both beginners and advanced trainees, the only variable being the intensity of effort.

The Preferred Pre-Exhaustion Training Routine:

  1. Horizontal Leg Curl
  2. Leg Quadriceps
  3. Leg Press
  4. Abductor/Adductor

These 4 exercises are performed with little or no rest between exercises. The feeling in the frontal thighs while performing the X-Force Leg Quadriceps has to be experienced to be understood. With almost any leg extension, the ache in the thighs “gets your attention.” With X-Force, that “feeling” is taken to a far higher level. With beginning trainees, we allow a “break-in” period of several weeks to a month or as long as it takes for the trainee to tolerate moving quickly from machine to machine to stimulate the greatest benefits. However, the exercises are ALWAYS performed slowly and smoothly, to a 3-1-5 count. 3 seconds up, a 1-second hold and 5 seconds lowering the resistance. After the four exercises are completed, up to a 2-minute rest is allowed for advanced trainees, more, if necessary for beginners.

  1. Lat Back Circular
  2. Lat Back Row

Performed with no rest, this pre-exhaust routine works the lats and entire upper back, of which no other routine is capable. Hard to believe? Try it once and you will understand. Very intense. Very efficient.

  1. Pec Arm Cross
  2. Pec Seated Press

These two exercises, which thoroughly work the pectorals, the deltoids and the upper arms, are alternated with the Deltoid Lift and the Deltoid Press the following workout. As described earlier in the article, this routine stimulates a far deeper inroad into the chest and shoulders than performing set after set of chest presses or overhead presses. The far more efficient inroad for this muscle group and every muscle group in the entire workout necessitates a longer  “systemic” recovery to allow the stimulus to take maximum effect.

  1. Biceps Curl
  2. Lat Back Pulldown

This is my personal favorite. I have been training with weights for nearly 50 years. That I have NEVER experienced a biceps routine like this is an understatement. Follow the Biceps Curls IMMEDIATELY with a set of Lat Back Pulldowns initiated with the biceps in a pronated position and during the positive stroke, twist the biceps into a supinated position into contraction. Hold the supinated position until the weight stack completely straightens before initiating the negative phase of the movement and slowly pronate the biceps as you near completion of the repetition. You will feel the “pump” in the biceps from the shoulder to the elbow, with the greatest emphasis in the direct center of the biceps. INCREDIBLE!

  1. Triceps Press
  2. Pec Angle Press

Granted, you might not have much left at this point of the workout. If you don’t, the triceps press will get the job done on its own. However, if you like to finish what you start, do both exercises, back to back. The Triceps Press takes some getting used to. Don’t start with too heavy a resistance. Instead, use a bit lighter weight at first, until you get used to keeping your elbows firmly on the pads, especially on the negative phase of the exercise. Once you get used to it, this machine will literally “tie your arms in knots.” The Pec Angle Press ends the workout. If you worked as hard as you should, you will be happy about that.

That’s it – THE WORKOUT OF YOUR LIFE. To me, nothing else comes close. Dr. Darden recommends, and I concur, that you train on each machine for approximately 6-8 repetitions, which should take about one minute per machine.  Experience at MLH&F has indicated that the higher repetitions are desirable for the Leg Quadriceps and Leg Presses. Go higher for the Leg Quadriceps due to the fact that the knee is the largest and least efficient joint on the body and most likely will respond better with higher reps (maybe 10-12). Go higher in reps on the Leg  Press due to the greater potential  overall systemic response stimulated by heavy, hard hip and leg work.

The results stimulated by this equipment have simply, yet definitely revolutionized training. I encourage you to try it. We have found it to be the “final breakthrough.” We would be happy to answer any questions about our programs and our use of X-Force.


(1). The effects of eccentric versus concentric resistance training on muscle strength and mass in healthy adults: a systemic review with meta-analysis (Roig et al, 2008).

(2)  Eccentric muscle action increases site-specific osteogenic response (Hawkins, S.A.) et al 1999).