Isometrics might not seem very exciting, but they can help you build muscle and strength like nothing else.
Isometrics: strength training without movement. It's a method championed through the decades by serious sports scientists and researchers. Many of the great modern-day strength coaches have been passionate advocates for isometrics: Louie Simmons, Pavel Tsatsouline, Christian Thibaudeau, Ross Enamait, and many more.
And yet, look around online, and you'll see very few athletes consistently using this method. Why? One reason is that there's simply not much to see. Isos aren't as exciting as a max-effort deadlift, or even a 20-rep set of old-school breathing squats. In fact, they're pretty much the definition of "unexciting" to witness. But once you practice them enough to get good at them, you'll find that isos can absolutely offer the same benefits as low-rep strength training or high-rep muscle training, along with some unique benefits of their own—and all with very little equipment needed.
Isometrics may be under the radar today, but back in the 60s everyone from businessmen to Olympic weightlifters was using them. Bruce Lee was a great champion of the method. In fact, you may have seen photos of him using a chain-and-bar device.
Chain-and-bar isos involve a footplate (or wooden base) attached to a chain, a spring, and a bar. The athlete stands on the plate and pulls or pushes the bar, just like a barbell, but isometrically. The addition of a heavy-duty tension spring on the chain mimics a "live" load. This makes chain work a massive improvement over traditional static-state methods—pushing on trees, walls, doorframes—because these approaches don't allow you to overcome what's known as "muscle inhibition." Basically, your nervous system knows when there's a load there, and unlocks muscle fibers accordingly. Athletes who used chain-and-bar devices said they could feel themselves getting stronger on a daily basis.
It seemed like isometrics were going to be the training method of the future. Then, seemingly overnight, isometrics passed out of training culture. Why?
The major argument against isometrics has always been the lack of measurement. How much force are you using? If you are pushing a barbell against pins in a rack you might know what's on the bar, but how much force is going into the pins? Nobody knew. Sadly, without knowing how much you're lifting, progressive overload is pretty abstract, and tracking progress is difficult.
This problem was partially solved by the addition of a simple dynamometer to chain-and-bar devices. The major issue here was that you couldn't see the meter during training, so you needed someone to call out the numbers. This is why the team at Dragon Door, with my help, invented the Isochain, the first-ever isometric chain-and-bar device with a digital readout display in the handle.
So maybe now you're thinking, "Hell, I'm a bodybuilder, not a weightlifter or a martial artist. Why should I use isometrics?"
You want a reason? I'll give you 10.
When physiologists were first able to study muscle growth properly using computerized tomography, they found that isometrics—if you use them right—build muscle just as well as conventional bodybuilding methods.[1]
Why are isos so damn effective for bodybuilding? Because one factor which is definitely central to optimal hypertrophy is time under tension. Isometric training is the ultimate time-under-tension method. This isn't anecdote or opinion—it's just simple math.
Imagine a barbell curl; the hardest (and most productive) point of the barbell curl is when the forearms are at 90 degrees, parallel to the floor. But this ideal angle only lasts for a split second. During a set of curls, the tension in the biceps is constantly going up and down, like a sine wave. At the top and bottom of the exercise, muscular tension drops almost to zero.
Compare this with an isometric curl; maximum tension can be held at any angle and you can make it last as long as you want—or as long as you can stand. It works because at any angle, isometric exercise increases intramuscular pressure, occluding circulation and resulting in anoxia (oxygen deficiency) inside the muscles. This anoxia, in turn, powerfully stimulates the synthesis of new actin and myosin in the muscle cells, to help them survive.[2] The result is bigger muscles.
For muscle building, sure, you can get by with time-under-tension techniques using moderate weights. But if you want to get stronger than the next dude in a hurry, you need to use heavy loads. There's no way around this. The heavier the loads you can use, safely, the closer you can get to your maximum strength potential.
Isometrics allow you to utilize heavier loads than conventional resistance training methods. This is due to a physiological law called the "force-velocity" relationship. In short, this law says the heavier the load gets, the slower we must move.[3] The moment your muscles are lifting the highest possible load they can handle, they stop moving. As soon as that happens, you are doing isometrics.
Unsurprisingly, the biology behind this means that isometric contractions allow athletes to recruit more muscle during training—like 100 percent of your contractile tissue. No other form of strength training can match this.[4]
Even the earliest studies of isometrics showed enormous strength gains, up to 5 percent per week.[5] Imagine doubling your strength in 20 weeks! It can be done and has been done using isometrics.
You might be thinking, "Yeah, but isometric strength is only good when you're not moving. It doesn't translate into real world, dynamic strength." Actually, the science shows that it does. Muscles that get stronger isometrically are also stronger when you're moving.[6] More on that in a second.
Unfortunately, slinging heavy iron can cause wear and tear on the joints over the years. It can also result in injuries, both chronic and acute. Serious heavy lifters just accept this as part of the game. If you love the feeling of lifting heavy but care about your joints and want to be lifting into old age, isos are definitely a strength discipline you should explore.
Injuries are often caused when soft tissues are exposed to external forces they can't handle—usually in a context of momentum, movement speed changes, and muscles lengthening under load. In isometrics, there is zero momentum and zero muscle lengthening. And the athlete's own nervous system determines the load it can handle. Isometrics—even isometrics using huge loads—are statistically the safer option.
One reason people avoid isometrics is because they're not fun. Serious isometric training, even for a short period, will illuminate your weak points like a laser beam. This is due to a principle of physiology called Sherrington's Law of Irradiation.
Sherrington's Law of Irradiation states that the more force a muscle exerts, the more surrounding muscles are activated to assist in the generation of power. For moderate forces, neighboring muscles are called in; the higher the force, the more distant muscles are recruited. Isometrics allow athletes to use the highest forces possible, as safely as possible. These loads force the entire body to work as a unit, under Sherrington's Law.
The take-home of this is that isometrics work the whole body as a system. If any muscle group is weak, stiff, or imbalanced, isometrics will tell you. Then, isometrics will fix it—rapidly. If you wish to make progress in isometrics, you must learn how to tense and brace your entire body. During every single session, you mentally and neurologically learn how to iron out weak links.
Don't believe that old fairy tale that isometrics only strengthen muscles at the angle you use them. This idea was disproved long ago by ergonomic models, and numerous experimental studies have challenged the concept of angular specificity.[7-10] Strength differentials at divergent angles are the product of leverage, not muscle activity.[11] Muscle cells follow the "all-or-none" law—they either contract, or they don't. They don't understand "angles".
Even if this weren't true, a huge amount of "functional" strength is isometric anyway. Look at something as fundamental as picking up a weight—your spinal muscles fire isometrically, your core fires isometrically, your upper-back and shoulder stabilizers fire isometrically, your grip is isometric, even the muscles of the feet work isometrically.
If you want to get flexible for life, you could do a lot worse than devoting some time to yoga. But what should you do if you want to improve your lifelong cardiovascular health?
The answer is, you should be exploring isometrics. One of my students calls isos "yoga for the cardiovascular system," for the sneaky benefits they can impart in just a few weeks.
Previous generations of doctors and coaches assumed that isometric training was bad for individuals with high blood pressure, purely due to the fact that your blood pressure rises during isometric training. (In fact, the same belief was originally held about all resistance training.)
But as soon as scientists began to seriously study this area, they found that isometric exercise reduces high blood pressure.
In one study, individuals performing isometric exercises three times per week over eight weeks saw their systolic pressure drop by 12.5 points, and their diastolic plunge by a huge 14.9 points—that's nearly two points per week, a potentially life-saving drop.[12] More recent studies have noted significant blood pressure drops after as little as four weeks.[13] The dramatic effect of isos on hypertension is so profound that some cutting-edge researchers recommend isometric exercise as an anti-hypertensive therapy.[14]
What's going on? The answer has to do with a physiological phenomenon we could call the "isometric effect." When you tense your muscles hard and hold them that way, the expanded muscles mechanically squeeze the veins and blood vessels running through them, like a vice. This constriction places the circulatory system under stress; as a result, it adapts—blood vessels quickly become stronger, more supple, and altogether more youthful.
This constriction also forces the heart to pump harder to maintain blood flow, making it healthier and more powerful; an improvement better than that seen from traditional, aerobic-type cardiovascular exercise.[15]
In fact, isometrics are so damn good for circulatory health throughout the entire body, that researchers are now exploring them as a therapy to help combat Alzheimer's Disease as a part of a full cognitive treatment plan.[16]
It used to be assumed that isos were useless for fat loss. You're not moving, right? How can that burn fat? But a comprehensive study published in The Journal of Applied Research demonstrated once and for all the benefits of isometric training as a fat-loss weapon. It showed subjects reducing enough belly size in the first two weeks of isometric training to drop one dress or pant size; by four weeks, some subjects had lost over 22 pounds in weight.
They did this while increasing strength by 20 percent, and—here's the kicker—with only 7 minutes of training per day. Subjects were eating a normal, healthy diet, with no drastic decrease in calorie intake. The team of researchers also noted an average drop in the iso group's cholesterol of 14 percent in just four weeks—enough to significantly lower the risk of heart disease.[17]
It might be hard to believe, but researchers have understood that isometrics increase speed for the better part of a century. The reason is simple: Isometrics make you stronger, and there is a proportional relationship between strength and speed. Strength is the production of force. Newton's second law tells us that acceleration = Force x Mass. No force, no acceleration. A weak athlete is a slow athlete.
That's the physics, but the biology behind this is also understood. Your fast-twitch muscle fibers adapt according to what's known as Henneman's size principle. This physiological law states that larger fibers—the fast-twitch ones—are only recruited (and trained) according to load, not speed. You need high loads to train fast-twitch fibers. Isometric training involves higher loads than speed training, or regular lifting. As a result, isometrics powerfully tap into the fast-twitch fibers. Isometrics make you fast, even though you're not moving.
Counterintuitive as this may seem, research has shown it to be true. Researchers at the Centre for Rehabilitation and Human Performance Research have shown that isometric training increases speed just as effectively as traditional explosive training.[18] Even cooler, this increase doesn't just translate to simple squat-like jumps, but also to more coordinated speed moves, like combat striking or sprinting.
Additionally, if you want to be fast as hell, your body has to be able to handle torque. Isometrics amplify this ability, whereas many other types of speed training don't. Isos are also better for the joints than other forms of explosive training.
You recover faster from isometrics than conventional pick-it-up-put-it-down lifting styles. Much faster. While a hard barbell session can leave you exhausted for days, athletes can recover fully from super-heavy isometrics in a matter of minutes and get on with their day, or even move to a different sport.[19]
Some of this has to do with muscle energetics: Isometrics don't heat up the interior of muscles or burn through chemical resources anywhere near as fast as regular training, a weird biological phenomenon called the Fenn effect.[20]
Even better, once you have some basic conditioning under your belt, isometrics—even with loads far greater than those used in the gym—barely leave you sore at all. The next-day aches and stiffness just aren't there. This is because the delayed-onset muscle soreness (DOMS) we all know and love is caused by microtrauma to muscle architecture when muscles lengthen eccentrically under load. In isometric training, the muscles are static under load—zero lengthening equals minimal damage and negligible soreness.[21]
Isometrics are the most efficient form of resistance training known to man. Some of this, again, is just math—with no wasted "easy" portions of a rep, isometric holds are significantly more time-effective than conventional sets-and-reps training. According to the legendary Soviet strength scientist Yuri Verkhoshansky, the ideal productive isometric strength session should be completed in approximately 10 minutes![22]
A full and productive isometrics session can be completed in less time than many athletes spend foam rolling as part of their warm-up. Think about that.
Add in the fact that isometric chain training can be done at home, and you've got a "super method" of strength-and-muscle building that doesn't leave you tired or sore, doesn't interfere with other sports or disciplines, and can be completed in just a few minutes.
Seriously, why aren't we all doing this?
Have I whetted your appetite for some isometric chain training yet? You want to get started?
Despite all the cutting-edge research behind it, isometrics, in my opinion, are the simplest and most elegant form of training. Here are some tactics to get you started:
Isometric training will get you stronger very fast. This is a good thing, but a corollary of this is that accommodation occurs sooner than with less efficient methods. If you want to make continual progress, side-step this problem exactly as you would with conventional lifting—switch up your training every 6-8 weeks. Apply different isometric exercises, training angles, lengths of holds, intra-set rest periods, volume, or training frequency.
If you make these changes, the progress will keep coming. The law of diminishing returns means it will slow down eventually—the same is true for all training methods—but don't sweat it.
Does all of this mean you should throw away your barbells, dumbbells, and kettlebells?
Hell no! These are tried-and-tested strength tools, and are all-around awesome for a number of reasons. I’m just saying that if you have an open mind, there’s another strength and conditioning tool out here waiting for you: and it’s one of the best on the planet, and now you know all the reasons why and mechanisms how.
So why not use it?
Strength training doesn't have to be complicated to be effective. Master the basics in Strength and Muscle for Beginners in BodyFit Elite! Get in and out of the gym in 3 workouts a week, so you can spend time doing what you love!