Zack Phillips, CSCS
Isometrics, or an isometric hold, is the body working against gravity or external resistance to maintain a static position. During an isometric contraction, the muscle’s tension changes to meet the challenge of fighting for position while the muscle length remains unchanged. Unlike a dynamic lift, where the contraction may last as little as 0.1 seconds, a maximal isometric contraction can be held up to 6 seconds.
The advantage of isometric work is that it requires little equipment, concentrates effects on a specific joint angle that may passed over by dynamic work, aids in kinesthetic awareness of correct movement patterns, and is time efficient. Isometric exercise is not a magic bullet but is an often-overlooked method of building strength. While isometrics have been used with success by both strength and conditioning and barbell sports to improve strength and explosive power, I feel that their most significant value to the tactical athlete is strengthening the ability to maintain posture and position while under stress.
Overcoming and Yielding
The two categories of isometrics are overcoming and yielding. An overcoming isometric is exerting a maximal force against a fixed object that will not move. Overcoming isometrics for combat athletes were popularized by Bruce Lee and are still used by boxers and wrestlers. Powerlifters and weightlifters use overcoming isometric lifts by pulling or pushing a barbell against the pins in a power rack. This type of maximal effort overcoming work is best used for increasing the rate of force development and building strength through an individual weak point, and it creates great tendon stiffness.
A yielding isometric is holding a position or a weight while fighting to resist gravity. You have probably performed yielding isometrics in your workouts without knowing you were doing so. If you have held yourself at the top or bottom of a push-up, sat at the bottom of a squat, or hung at the top of a pull-up bar, you’ve performed yielding isometrics. Bodyweight and lightweight-yielding isometrics are best used to develop postural control and strength.
How an Isometric Hold Works
- Isometrics build strength by activating up to 5% more motor units than a concentric or eccentric contraction. The muscle is trained while holding the body position under tension for longer than that position could be maintained if the athlete was straining against a maximal load in a back squat or bench press.
- An isometric contraction will build strength about 15 degrees above and below the joint position trained. If you’re trying to build power from the bottom of a push-up, holding two inches off the ground will strengthen a couple of inches above it.
- Because isometrics are the fastest type of muscle contraction, they will increase the rate of force development, meaning the ability to voluntarily produce a maximal explosive muscle activation.
Benefits to Tactical Population
The primary benefit of isometrics to the tactical population is their use in strengthening tendons and building postural stability. The stronger an individual’s tendons and connective tissues are, the more resistant they will be to damage from tensile loads.
- Isometric training produces great muscular tension but also trains the body to accept great tension rates in specific positions.
- The daily physical work and loads carried by military, police, and fire and their associated energetic costs cause compensatory adjustments to gait and posture, contributing to injury risk.
- By strengthening the ankle, knee, hips, and neck to resist cumulative fatigue and sudden impact forces from a parachute landing fall, vehicle collision, or an awkward landing during a pursuit, the soldier, police, or fireman may experience a longer and less painful career.
The easiest way to benefit from isometric training while staying on your existing training program is to incorporate tempo into your repetitions. Tempo is the speed at which an exercise is performed. It is expressed numerically as eccentric, iso bottom, concentric, and iso top. I prescribe tempo on most exercises for everyone I train.
- For example, 1-3-X-3 is a one-second eccentric, three-second isometric hold at the bottom, explosive concentric, and three-second isometric hold at the top.
- Imagine hanging on a chin-up bar. You hang free and hold yourself in a hollow body position for three seconds, then you explosively pull yourself to the flexed-arm position at the top and hold for another three seconds; you control yourself back to the starting position by lowering your body for a second. That is a 1-3-X-3 tempo.
- Try adding a three-second hold at the bottom of your split squats, bench press, or lock-out of a barbell press, and progress that to six seconds over the next few weeks.
Another way is to start adding iso-hold exercises. Because of the nervous system fatigue that can accompany isometrics, these should be performed toward the end of the session.
- Use these holds to strengthen the joint angles that are most relevant to your occupation; partner-resisted neck exercises, tip-toe squats, PNF stretching, and chin-up holds are good options to use.
- Heavy, weighted holds or overcoming pulls or presses should be held for three seconds, progressing to six seconds.
Lastly, running a full isometric-centered macrocycle is a method that some teams have used. Tim Grover, who trained Michael Jordan and Kobe Bryant, used long isometric holds (up to two minutes) of bodyweight squat and lunge holds followed by quick half-reps, static stretches, and hip mobility exercises.
Drawbacks and How to Mitigate Them
A high volume of isometric exercises can cause central nervous system fatigue, increase blood pressure, decrease speed and coordination, and reduce elasticity.
- These effects can be controlled by using correct breathing patterns, dosing volume, holding length appropriately, and prescribing rest and stretching between sets.
- Because of the impact on the circulatory system and intramuscular connective tissue, I recommend pairing the holds with mobility and movement exercises to keep the joints articulating and the blood moving.
Isometrics will not replace dynamic strength work and should be accompanied by isotonic movement. Accommodation to isometric exercise is usually quick. Most well-trained athletes will see the peak effects after 6-8 weeks or 1-2 mesocycles. When conducting isometrics in your training, ensure the effort is all-out; hold for a duration where that effort can be maintained; rest long enough that an all-out effort can be repeated (1-3 minutes); and prioritize training movements and joint angles at their weakest point.
The effort being applied is subjective, but the closer the load is to the individual’s maximum strength, the shorter they can hold maximum tension.
- Bodyweight holds can be 20-30 seconds and progressively longer throughout the cycle, depending on the strength of the individual.
- Overcoming pulls and presses into power rack pins will be shorter; 3-6 seconds is the range where a true max effort can be held. Verkhoshansky recommended that the total duration should be at most 10 minutes in a session.
- The effectiveness can be assessed by employing the isometric mid-thigh pull test on a force plate, if you have access, or by using a designated weight for a hold and tracking the length the individual can hold throughout the program.
Three bodyweight/lightweight iso holds I like for both tactical and sports athletes are a neck bridge, plantar flexed squat hold, and pull-up/chin-up hold. I have used two consecutive three-week cycles of two days a week of isometric-based work with two days of traditional dynamic work.
Neck bridges build postural strength in the neck, which helps reduce concussion risk. I like to do these on a bench, but beginners should start by doing them on the floor. Lay face up on the floor or bench with your knees up and bridge your hips up while balancing your weight on your feet and head. Hold for 5-10 seconds, lengthening the hold for 20-30 seconds over three weeks. Progress these by doing them face down, with the forehead and toes as the contact points.
A plantarflexed squat hold is a bodyweight squat performed on the tip-toes instead of the whole foot and held at a 90-degree, flexed position at the bottom. As mentioned, pumping out 5-15 reps of tip-toe squats after a hold will help restore blood flow. Try three sets of 30-second holds followed by 15 quick reps. If you can do 3×30 seconds, progress to 45 and 60 seconds over three weeks. To further progress in difficulty, do a front foot elevated split squat hold; an advanced athlete can hold two dumbbells in a suitcase position.
Chin-up and pull-up holds may benefit full-range pull-ups, but their primary benefit is building strength and stabilization in the core and lower back while strengthening the biceps tendons. Hold yourself in a flexed arm, hollow body position at the top of a pull-up bar for 20-30 seconds, then bang out a couple of quick reps of chins or pull-ups.
Zach is a professional strength and conditioning coach and US Army veteran.
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Grover, T. (2014). Jump attack: The formula for explosive athletic performance, jumping higher, and training like the Pros. Scribner.
Verkhoshansky, Y., & Verkhoshansky, N. (2011). 2. In Special Strength Training: Manual for coaches (pp. 81–83). essay, Verkhoshansky SSTM.
Zatsiorsky, V. M., & Kraemer, W. J. (2006). 6. In Science and practice of strength training (pp. 124–126). essay, Human Kinetics.
Bio: Zack Phillips, CSCS, a former airborne infantryman, is the strength and conditioning coach for the basketball, baseball, and cross-country teams at New Mexico Military University.