You can use an extra set of pins to pull against, or you can use the guards to create a barrier (pictured). It should be noted that the rack should be bolted to the floor or weighted very, very heavily to prevent tipping.
Some basics: in an isometric contraction, the muscles don't shorten as they do when an exercise is done with a barbell or dumbbell. They do shorten when an isotonic exercise is performed.
What Ziegler did was COMBINE the two for MAXIMUM results. [Genius!] He found out early on that by moving the bar a short distance - usually no more than a couple of inches - before locking it against a set of pins and holding it for an isometric contraction was more productive than doing just an isometric hold.
First of all, doing so eliminated the guesswork as to whether the athlete was putting his maximum effort into the movement. With the combination, the loaded bar stayed fixed against the top pins or it didn't. So if the athlete was unable to hold the weight for the required period, he needed to lower the poundage. If he was able to hold the weight against the pins for a much longer count than what was required, then he needed to increase the weight on the bar the next time he did that particular position in the rack.
One of the most important advantages of moving the weight isotonically before locking it into an isometric contraction was that the athlete could gauge his progress from workout to workout. If, for example, he was using 205 lb. for the middle position of the overhead press a month ago and now he's handling 225 at that same position, he knows he's getting stronger. That's very motivational and something that's lacking in pure isometrics, where there isn't any tangible proof that the athlete is making progress.
Then there is the motivational factor in regards to the psychology of numbers. Strength training is all about numbers: sets, reps, time spent training, rest periods, workload and top-end numbers. It's much more satisfying to be able to lock 365 against the pins while doing a starting position in the clean pull than it is to do the same movement with an isometric contraction.
In addition, an athlete can break form while doing an isometric hold and not even realize it. But when there is a considerable amount of weight on the bar, if he pulls, pushes or squats out of the correct line, he will not be able to lock the bar against the pins for the isometric hold. The isotonic move requires that the athlete control the bar, because if the bar isn't moved in the exact line it needs to be in, and if the athlete's body is not in the exact position it should be for the exercise he's working on the rack, that set will be a wash.
When an athlete does an isotonic-isometric movement, he's forced to concentrate much harder on what he's doing than when he does a full range motion for the exercise and also when he just does a pure isometric hold. This forces the nervous system to become involved to a much greater extent. This is why the combination of isotonics and isometrics is so much more demanding than pure isos and why it takes more time to recover from rack work.
The first thing you need to do if you want to try this form of strength training is buy a notebook. You must record every workout. Otherwise you're going to forget exactly where you set the bar in the rack for the various exercises, how much weight was on the bar, and you're also going to forget exactly how long you held the bar against the pins for the isometric contraction. Most believe they can remember. They can't. Not unless they write it all down.
And it's best to do it while you're training, because even a few hours later not many people recall what hole they used in the rack for the three squats positions they did that day.
It's also a good idea to put small strips of tape next to the holes in the power rack and number the holes. That will save you the time of counting up to hole you're after at every rack session. Start keeping a record from the very beginning and it will become a regular part of your workout.
Be sure that you're completely warmed up before performing any isos. I will refer to isotonic-isometrics as "isos" for the rest of this article.
When I first introduce isos to one of my athletes, usually just those who are advanced and have been training with me for several years, I put them at the end of the workout so they are already warmed up thoroughly. But if you happen to want to start off with an iso, be sure to spend time raising your pulse rate and getting your muscular system ready for the upcoming work.
I have found that the middle pull for the clean is the best position to teach someone how to do isos. It's a strong position for most athletes and particularly so for Olympic lifters and powerlifters and those who include power cleans in their programs.
Use straps on all pulling movements in the rack.
Set the bar a few inches above the knees.
Some power racks have holes four or six inches apart, and in order to set the bar where you want it, you need to stand on some blocks. This may seem awkward at first, but with practice you can get used to it.
Strap onto the bar and make sure your body mechanics are absolutely perfect: feet in the right position, back tight, frontal deltoids slightly out in front of the bar.
Take a breath, drive your feet down into the platform, then ease the bar up against the top pins.
Most attempt to jerk the bar up the the pins, but what usually happens in those cases is the bar will dance away and come crashing back to the lower pins. Squeeze the bar upward and fix it snugly against the top pins.
Once you have it securely in place, start your count and begin applying more and more pressure on the bar. When the counts hits five, lean into the effort even harder and at that juncture every muscle in your body should be fully contracted, from your feet to your traps.
Whenever you do an iso perfectly, you'll feel an electric shock shoot up through your body into your brain. That's what you're after: a maximum contraction.
What you're trying to do is bend the bar. While Doc Ziegler was right about not being able to put out 100 percent, with practice you can get very close to that percentage of effort. at the end of the iso contraction, take a couple of deep breaths and lower the bar back to the lower pins in a controlled manner. This provides a bit more work for the target muscles in the form of negative training.
How long should the contraction last? Doc Ziegler believed that a short 6-8 second count was enough. But he was dealing with experienced lifters. Most athletes that I introduce to the iso system are not able to apply themselves fully until they have locked into the iso hold for 5 or 6 seconds. So I have them hold for a slightly longer count: no less than 8 and no longer than 12.
Sets and Reps
Doc's program was for 1 set of 3 different exercises for the back squat, presses, and pulls, plus a few auxiliary movements such as calf raises and even good mornings. I teach the isos in a slightly different manner to allow the athletes to get the feel of what they're trying to accomplish. I have them do 3 sets instead of just 1. It goes like this:
My sample athlete is going to do the middle pull and wants to finish with 325 for a count of 8-12. For his first set, he uses 225. He pulls the bar to the top pins but doesn't lock into an iso contraction. He just taps the pins and lowers the bar back to the pins. A second rep is done in the same fashion. The third rep is the money rep, and he holds it for just 5 seconds to get the feel of the iso contraction.
Next, he uses 275 and follows the same procedure as he did on the first set: tap, tap, hold for a count of 5.
On the third, final set, he will only do 1 rep because he now has the line down and knows how to lock into the iso contraction. He holds for no less than 8 seconds, and if he moves easily past a count of 12, he will load on more weight the next time he does that position. Over time, he will eliminate one or both of those warmup sets and go directly to the work set, but while learning the technique for this form of exercise, a few warmup sets help.
Once you have learned how to do isos from the middle pull position, you can do them for any exercise in your routine. They are absolutely the very best way to improve a weak point and an excellent way to find the weakest area in any given exercise.
The one point that Ziegler emphasized over and over was that the time element was far more important than how much weight was on the bar. If a certain poundage could not be held for the required count, less weight should be used.
When an athlete did manage to hold a weight for a solid 8 seconds, then he had to stay with that same weight until he could lock it in as an isometric hold for 12 seconds. Then there's no doubt that he is getting stronger in that particular position.
What you're doing is overloading those muscles and attachments in a very short, concentrated expenditure of energy. When done correctly, 1 set of 1 rep is enough. Doc also said that whenever the muscles, tendons and ligaments are pushed to absolute limit, they're through for that day.
Isos are ideal for getting in a total-body workout in a short period of time. Three positions for any form of pressing, three pulls, and three more for the hips and legs and you're finished. if you use your imagination, you can figure out how to do a large number of different exercises using isos, such as bentover rows, curls and inclines.
It will be well worth your while to take the time to learn how to do isos, if for no other reason than you will be able to teach an aspiring strength athlete how to do them in the future.
To me, isos are the ultimate strength exercises and they need to continue to be a part of every athlete's strength routine.
- Written 2010.