What are Isometrics? – Isometric Strength Training

by | Fitness, Health, isometrics

Isometric exercise or isometrics are a type of strength training in which the joint angle and muscle length do not change during contraction. Isometrics are done in static positions, rather than being dynamic through a range of motion.


A system of physical exercises in which muscles are caused to act against each other or against a fixed object.

Isometric Strength Training Techniques

Isometrics have been a common form of strength training for decades. Many say Alexander Zass was the pioneer for making isometric strength training techniques known and popular. The Russian discovered isometric strength training’s potential when he was captured and imprisoned during World War One, four times.

Yes, he was imprisoned four times and escaped every time. In fact, it was said he broke chains and bent the prison bars during one of his escapes. How can a person break metal?

Zass would constantly apply force to his imprisonment materials such as his chains and bars. After all, there was not much entertainment being a prisoner of war. After applying constant tension, he soon realized he was building his muscular strength. Before long, he noticed he was bending the metal bars and chains and finally with a final effort, he was able to break loose.

Zass was one of the original strongmen who demonstrated incredible fetes of strength. One of Alexander Zass’ performances was carrying lions on his shoulders during his circus act, where he ended up as a career entertainer and strongman. Another impressive story was him carrying his wounded horse during battle.

He later went on to develop various forms of common isometric strength training techniques in which many are still performed today.

Isometric Training Techniques

What are isometrics in laymen’s terms?

Isometric strength training techniques are effective methods to build strength which require little to no movement of your joints. Many doctors and physical therapists encourage isometric strength training for the exceptional development it has for strengthening tendons and ligaments. Therefore, doctors and physical therapists emphasize isometric strength training as part of their patient’s rehabilitation programs as well. The little movement creates a safer exercise to help muscles build without re-injury.

In addition, the lack of movement in the joints helps people with arthritis perform effective exercises for strength training without the pain of common exercises like lifting weights.

How can I use isometrics?

Isometric strength training techniques are an effective form of strength training and can be used as stand-alone practices or to help overcome plateaus in other forms of exercise and strength performance activities.

Isometric strength training techniques are proven to be effective for strengthening muscles and can be used to complement other forms of exercise like isotonic and Iso-Motion®. The development of your tendon and ligament strength is a huge advantage isometrics offer as this helps reduce injury and improves your overall performance.

How long should I hold the isometric hold?

Many studies have been performed on how long one should maintain their isometric hold. We recommend, similar to Twiea, the 7-second isometric hold at 60%-80% of your maximum effort for optimum results.

What are common isometrics exercises?

The Plank

The common abdominal and core exercise, the plank, is a perfect example of an isometric strength training technique. You are engaging your muscles at a static joint angle and your muscle length does not change.

Wall Sits

When you lean into the wall in a squatting position and hold, you are performing a common type of isometrics (isometric strength training) as you are engaging your muscles and exerting force with no change in your joint angle and muscle length.


Yoga utilizes isometrics with every shape. Many people think of yoga as a relaxing stretch, however, though you are stretching your muscles, most shapes/poses incorporate isometric strength training techniques if done properly.

For example, when you are in the crescent lunge pose not only are you holding the stance but, to enhance the pose, you should create an isometric contraction by activating your muscles. One way to do this is by pulling your legs together (without movement by maintaining your stance). Yoga is a sequence of isometrics as you hold poses throughout your sequence creating a muscle contraction at a given joint angle without movement.

What are some key things to remember during isometrics?

Never hold your breath – it is common for people engaging in isometric strength training to hold their breath during the isometric exercise. Though some may suggest it is part of the workout, we always advise you to breathe consistently or exhale during the hold.

Concentrate on activating your muscles – muscle concentration and active flexation is important for your best results. Concentrating on the muscles being engaged during isometric strength training helps you not only exert proper form and engage your desired muscle fibers but helps your mind-muscle connection and coordination as well.

Do isometric exercises only strengthen a small amount of your muscle’s range of motion?

Perform isometric exercises at various angles to strengthen various ranges of motion and your entire muscle range. Isometric strength training techniques have been criticized because they are thought to only strengthen the muscle at that particular angle.

However, studies have shown isometrics strengthen +/- 15 degrees on both ends of your practiced joint angle. Therefore, we recommend breaking your entire range of motion into thirds. If you perform 3 isometric holds at 1/3, 2/3, and 3/3 you will engage more muscle fibers and build strength for your body’s full range of motion faster than lifting weights.

Answer: Isometrics can enhance your strength and muscles for your entire range of motion.

Are there studies on Isometrics?

The most significant breakthrough in fitness came when Dr. E.A. Muller and Dr. Th. Hettinger discovered maximum muscle growth can be attained by exerting 60% of existing muscle strength against a superior resistance for only 7 seconds once a day; a remarkable fitness technique known as isometrics. The study at the Max Planck Institute consisted of over 200 experiments for a ten-year period. Optimum results are attained with 5 workouts per week, but impressively, even one single weekly workout is sufficient to maintain your improvements attained.

Professor James A. Baley put isometrics to the test with a class of college students at the University of Connecticut. The study resulted in the isometric training group improving three times faster than the sports training group on tests measuring increases in strength, endurance, coordination, and agility.

Bullworker pioneered portable home fitness devices and the 7-second isometric exercise for the fastest strength gains using both contraction and extension movements involving range of motion for enhancing all your major muscle groups.

Isometric exercise techniques are still the fastest method for increasing strength known to modern exercise science.

Please leave your comments and questions below. We are happy to address your questions in our future posts. Stay tuned for more during the isometric strength training technique series.