Rack work for strength and size Part III: Overcoming and functional isometrics
Isometrics refer to an exercise in which the muscles are contracting without changing length/moving. And despite that fact, they are among the best methods to overcome a strength plateau.
In fact, I’d be willing to say that both overcoming and functional isometrics are the best tools to quickly fix a sticking point in a main lift.
And understand that when you hit a plateau on a lift, more often than not it’s because of a specific sticking point; you might be strong enough overall to bench press 350lbs, if at your sticking point you can only move 325lbs that’s what you’ll bench (or a bit more if you are good at creating a lot of momentum prior to the sticking point).
As such, one way to address the issue is to focus on that sticking point and that’s where overcoming and functional isometrics come into play.
OVERCOMING VS FUNCTIONAL
Let’s first differentiate between both types of isometrics:
In overcoming isometrics you are pushing/pulling against an immovable resistance. The most common application is to push/pull a bar against the safety pin in a power rack. You don’t add weight plates on the bar; but you push/pull with maximal or near maximal effort into those pins.
Functional isometrics include some short-range movement and a loaded barbell. You need two sets of safety pins. The barbell starts on the lower set of pins and you press it into the second set of pins about 4-6” higher. When the bar reaches the higher set of pins, you proceed to push/pull as hard as possible against it.
Typically, the isometric phase in both methods is 3 to 6 seconds long.
PROS AND CONS OF BOTH METHODS
The functional isometric method is more powerful and effective at fixing a weak point? Why? Because it feels like what happen when you hit a sticking point in a lift: you are moving a heavy load and suddenly hit a point in the range of motion where you have o strain and grind to keep the bar moving. Neurologically, the more similar in dynamics to the main lift a supporting/corrective exercise is, the greater the transfer.
In a functional isometric, you are using a load close to your max (typically 85-90%). And while it’s only over a short range of motion, it still feels like you are lifting a weight. And hitting the top safety pins feels like hitting the sticking point.
With isometrics you are essentially training your neuromuscular system to be able to strain against a load to overcome that sticking point.
Overcoming isometrics also work, but a bit less due to a lesser neurodynamic correspondence. However, their benefits are that they are a lot less fatiguing (don’t impact recovery as much) and are less time consuming (you might only need 1 warm-up set but with functional isos you need to gradually ramp up to your training weight).
Another benefit of functional isos is that you can more easily qualify progression as you can increase the weight. While it doesn’t tell you total force production, it can provide an element of motivation.
WHERE IN THE RANGE OF MOTION?
The important question to answer is “where in the range of motion should I do the iso?”
Instinctively, you’d answer: “At the sticking point”.
And that would work. But it would not be the best position.
See, the sticking point (where you miss a lift) isn’t your weakest point; it’s where you ran out of steam. The true weakest point is likely around 1” lower than the sticking point; that’s where your speed drops due to a strength deficit.
The answer to “where should I do my iso” is:
“Around 1 inch lower than your sticking point”.
HOW LONG? HOW MANY SETS?
The main purpose of overcoming and functional isos is to rapidly increase strength gains in a specific position (isometrics does rapidly increase strength but only at the joint angle worked +/- 10-15 degrees). As such, you want to perform sets with the highest possible force production. You also want to train the nervous system to be able to strain for the time required to move through the sticking point.
As such, the best time to use for both types of isometrics is 3 to 6 seconds.
Longer than that and force production decreases too much to be of value.
Shorter than that and you don’t train the CNS to strain to go through the sticking point.
The “sets” can be done two different ways:
- ONE all-out, eye popping intensity, rep lasting around 6 seconds.
- 2. 3-5 reps at around 90% of your maximum force production for 3 seconds each (with around 2-3 sec break).
The first one gives you the most bang for you buck and provides pretty much exclusively neurological gains.
The second application will provide a moderate hypertrophy stimulus while still providing and adequate neurological improvement.
As for the number of sets, 2-3 work sets per position seems to work best. Overcoming and functional isometrics provide such a strong stimulus, while providing little metabolic/felt fatigue, that it’s easy to overdo them.
One last variable is the rest period. With isometrics we instinctively take rest periods that are too short. That’s because they don’t “feel” tiring. So you reason that you can go 30-45 sec after your set.
That’s a mistake because the nervous system takes almost 6 times longer than the muscles to recover. If you start your set with a “fatigued” nervous system, it sends a weaker excitatory drive to the muscles, making it much harder (even impossible) to recruit a high percentage your fast-twitch fibers and make them fire fast (high firing rate), making your set a lot less effective, even counter-productive.
I recommend 90 seconds (even more) between sets to maximize effectiveness.
WHEN TO DO IT IN A WORKOUT?
If you are using overcoming/functional isometrics to fix a weak point you should do It after the main lift (you can use the main lift performance to select the position to train) but not too late in the workout because you would have some central fatigue that would significantly decrease the effectiveness of the method.
Personally, I recommend this order:
A. Main lift
B. Isometric to fix weak point in the main lift
C. Major assistance exercise (multi-joint) to address weak point in the main lift
D – F. Single joint exercises for the muscles involved in the main lift
G. Back exercise
NOTE: You can also do it first in the session. This obviously allows you to do it with the freshest nervous system possible, and could act as an activation for the main lift.
However, it could potentially hurt performance of the main lift.
In a periodized cycle you might want to do the isometric exercise first for the first block of training (weeks 1-4), then doing it after the main lift for the second block (weeks 4-8_, and drop it in the 3rd block (weeks 9-12).