by Steve Holman Iron Man Magazine
Q: Iím using the simplified X-centric Mass Workout [pages 21-23 of the e-book], so I do two exercises for each muscle, the first in heavy, pyramid style and the second with a 4X sequence. I can already see new mass gains after only two weeks. Impressive. Thank you. My question is about rests on the first exercise pyramid. I like to train fast, so is two minutes between sets enough, say on bench presses for chest? Iím using 30 seconds on the second [isolation] exercise with 4X.
A: On the first sets for each big exercise you add weight in typical pyramid style. Your reps will go something like 9, 7, 5. Keep in mind that youíre trying to generate maximum force to affect the myofibrils, the force-generating actin and myosin strands in the muscle fibers. Letís look at the exact chest routine from that X-centric Mass Workout:
Bench presses (pyramid) 4 x 9, 7, 5, 7NA
Cable crossovers (4X) 4 x 10
You do a similar routine for every muscle: You add weight over three sets on the first big exercise, and then on the last set you reduce the weight so you can do one-second positives and six-second negatives for seven reps. That negative-accentuated, or X-centric, set will give you a long tension time of 49 seconds, which adds further trauma to the myofibrils with slow negatives and transitions the muscle into growth-threshold mode for 4X on the second exercise.
On crossovers you focus on expanding the sarcoplasm, the energy fluid in the muscle fibers, with 4X. You pick a weight with which you can get 15 reps, but you do only 10; rest 30 seconds, and then do 10 moreóand so on for four sets, going all out on the last one. If you get 10 on the last set, at your next workout either add weight to that exercise or shoot for 4◊11. Now youíve covered both power and density, the mix for maximum muscle immensity.
Okay, letís finally get to your question. To stress the force-generating myofibrils optimally on the first exercise, you should make your rests at least two minutes; however, it can take longer for the muscles and nervous system to regenerate to maximum capacity. Thatís why powerlifters often rest four to five minutes between sets.
Two minutes may be fine, but if you have the time, I suggest you try three minutesóat least on your most demanding compound exercises, like squats, bench presses and chins.
The three-minute rest time is based on research conducted at the University of Kansas that shows the correlation between optimal rest and force production on the bench press. Trainees who rested for three minutes between sets did the best at producing force on their second setómore than 30 percent better than trainees who rested for about half as long. The researchers also found that resting longer, even up to five minutes between sets, did not improve force production.
So science says that you should use three-minute rests for best force-production capacityóthat is, myofibrillar stress and growth. Then you can take short rests when youíre striving for a sarcoplasmic blast for extreme mass.
Editorís note: Steve Holman is the author of many bodybuilding best-sellers and the creator of Positions-of-Flexion muscle training. For information on the POF DVD and Size Surge programs, see www.Home-Gym.com. Also visit www.X-Rep.com and X-Workouts.com for info on X-Rep, 4X and 3D POF methods and e-books. IM