A lot of lifters forget that there are three basic types of muscular contractions: concentric, which is contraction while the muscle shortens, eccentric, contraction while lengthening, and the all too-neglected isometric. That’s when you work a muscle without moving it at all.
During a strength athlete’s eternal quest to hoist heavier and heavier loads from the beginning to the end point of an exercise, the middle portion of a movement – say, when a barbell is at knee-level during a deadlift – can swiftly become a lifter’s weakest link.
Most of us know this, but few of us spend time working in this middle range of an exercise. That’s where isometrics come in: they have an extremely effective, yet underappreciated and underutilized ability to improve the smoothness and efficiency of a lift’s entire range of motion.
“Isometrics get shafted and pushed to the side as this kind of useless part of a repetition, but they actually have a ton of transfer over to athletic performance,” says Eric Johnson, CSCS, co-founder of Sons of Strength. “A lot of the time, force gets lost during the process of a lift, and by adding time under tension in that isometric phase, you can basically transfer from the eccentric to the concentric a lot more efficiently and have a better rate of power transfer over time.”
They can also be great form fixers. Johnson points out that in the bottom of a squat, many people experience the infamous “butt wink.” But if a person can learn to hold that position with correct form while loaded up with a bar, they’ll become more comfortable in that and other sticking points in which they feel the most vulnerable.
It turns out that this sort of exercise is fantastic at recruiting muscle fibers as well. A widely-cited study published in the Journal of Applied Physiology, for example, showed that maximal isometric contraction of the quadriceps resulted in over five percent more muscle fibers activated than during a maximal eccentric or concentric action. That means isometric training can improve your ability to recruit motor units, which could increase strength and power production overall.
The Mind Muscle Connection
This is always a tricky topic to examine – it just sounds so mystical – but warming up with isometric exercises could help muscles to fire appropriately.
“Most of us just want the bar to get from point A to point B as fast and efficiently as possible, but you want the right musculature to be working,” says Johnson. “You want to feel like you’re initiating from the hamstrings and glutes on that first pull, driving your feet through the ground, and feeling tension in your lats. If you work in an isometric phase during your warmup, it helps to turn everything on in a sense, to stimulate these muscles so that way they’re fired up and ready to go. That way when you go to lift, you’re just focused on your lift and you’re not focused on that mind-muscle connection. It’s already been ingrained within your performance.”
How to Incorporate Isometric Movements
On the micro level, there are a few ways to work isometrics into a given strength workout.
During a warmup, you can try using loads that are about half your working weight, like the deadlift preparation described above, to stimulate your muscles and (possibly) improve the mind-muscle connection. With slightly heavier loads, isometrics holds can be used throughout the range of a deadlift to help ensure a neutral spine during the movement. Johnson recommends doing this kind of workout on its own, as opposed to using it to warm up for very heavy reps – your muscles will probably be too fatigued.
Another method is supra-maximal loading, which is a kind of post-activation potentiation. This involves loading a bar with 120 to 150 percent of your one-rep max and holding it at lock out. He describes it in the video below.
The goal is to holding the weight for three to ten seconds while bracing your muscles, crushing the bar, and pushing into the floor. Then you can rack the bar, adjust the weight, and start your working set – busting out reps will suddenly feel a lot lighter. He recommends this for compound movements like the bench, pull-up, and squat. For the latter exercise, push your hips back a tiny little bit before locking into the position
Pulling or pressing into an immovable object is another way to improve isometric strength. Take the bench press: you can set up safety pins in a squat rack at the height where you’re weakest in the movement and press the bar into those pins as hard as you can. Just remember that getting strong in those positions aren’t worth much if your form is flawed.
“I also love isometric holds as finishers, especially if you can use them to help improve mobility,” says Johnson. The goal is to stretch under tension. Here, he demonstrates with an isometric Bulgarian split squat in what he calls an “extreme loaded stretch.”
When you’re in the bottom of the exercise, squeeze the glute of the leg that’s on the bench. You can make the stretch even deeper by elevating the front leg. Other examples include holding the bottom of a push-up while the pec is stretched or holding a dead hang at the bottom of pull-up.
On a macro level, if you’re looking at a twelve- to sixteen-week training program, Johnson would concentrate isometric training during the two to four weeks in the middle. This helps to shore up sticking points as your lifts are progressing and, because isometrics don’t cause much wear and tear on the joints, it helps your body to recover mid-program as well.
Lifts aren’t just lifts. The bar doesn’t just exist at the beginning and end of a movement; it moves through a range of motion that for many of us, is pretty weak around the midpoint. After all, when struggling to increase lifts, many athletes will notice that they don’t lose strength at the start of the movement, they lose it at the halfway point: when the bar is a foot above the shoulders, or when the deadlift hits the knees. Strategically using isometric exercises is an underutilized, but very effective tool that could prove the missing link in hitting your next PR.
Featured image sourced from @sonsofstrength