The Benefits and Limitations of Isometric Training

4 min read

shutterstock_212236066 There are always new training techniques coming out with claims they’ll give you massive gains, but some of the original techniques are still the best. Isometrics is a practice which predates modern bodybuilding training methods, but research proves that those pioneering strongmen were on to a good thing.

Strongman Alexander Zass developed isometric techniques while he was a prisoner during World War I by pulling and pushing on his prison bars. Isometrics underwent a revival in the 1930s under the influence of pioneer bodybuilder Charles Atlas, but it fell to the background as free weights, such as dumbbells, became more popular.

Isometrics comes from the Greek words isos, meaning equal, and metria, meaning measuring. An isometric contraction is one in which the muscle doesn’t change in length, so there is no movement. The muscle feels tense because the tension at the cross bridges is equal to the resistive force. Holding a barbell at 90 degrees, pushing against a wall, or standing in a half squat position are all examples of isometric contractions.

Isometric styles

Different isometric styles are used to achieve different results.

Overcoming isometrics

Pushing against an immovable object, such as a wall, is described as overcoming isometrics. This style of isometric training has a greater effect on concentric (lifting or pulling) strength.

Maximal effort isometrics

This is a variation of overcoming isometrics, where maximal tension is generated quickly and applied against an immovable object where it is held for 3 to 5 seconds. This technique is especially good for building strength and muscle volume. While this technique can be used in a variety of situations, it is especially suited to pin-loaded machines where you can put the pin at the bottom of the stack and attempt to lift the stack in 3 to 5 second bursts.

Yielding isometrics

The technique of stopping a weight from lowering is known as yielding isometrics. Yielding isometric techniques have a greater effect on muscle mass and eccentric strength. You may see experienced bodybuilders doing this with barbell curls to help develop strength at sticking points.

Maximal duration isometrics

This is the most common form of isometrics you’ll see in the gym. It involves pushing, pulling, or holding a sub-maximal load for as long as possible, and is good for muscle growth and strength endurance. Examples are hanging from the chin-up bar or holding the plank position for 20 to 60 seconds.

Explosive/ballistic isometrics

One technique that crosses over with sports requiring speed and strength is explosive or ballistic isometrics. It involves creating bursts of tension for 1 to 3 seconds, and is often used in martial arts and sprint training. Some studies have shown significant gains in peak force and speed when explosive isometrics complemented a dynamic weight training program.

Static dynamic isometric

Russian sports science great Yuri Verkhoshansky found that traditional weight training regimes were far more effective when supplemented with isometric techniques. A static dynamic isometric exercise begins with a 3 to 6 second hold, followed by a regular set. An example of this might be loading up the leg extension machine to an immovable weight, pushing against it for 3 to 6 seconds, and then moving the pin to perform a regular set.

Benefits of isometric techniques

  • Isometric exercises can be performed anywhere and often don’t require equipment. This makes them ideal for travellers or for pumping up before posing. Isometrics don’t demand a lot of energy or time, so they’re also a great way to train when you don’t have the time or energy for a full workout.
  • Maximal isometric contractions recruit more motor units in the muscle than any other technique which, in theory, means that isometrics should be the best regimen for strength gains. Research as far back as the 1950s showed that a daily routine of 2/3 effort for 6 seconds can increase strength by 5% per week. More recent studies have recorded strength gains of 14-40% over a 6 to 10 week period.
  • Isometric techniques are popular with athletes trying to get through sticking points, the weakest angle through a range of motion, or for strength building at specific angles
  • Isometrics don’t have to be an either/or training regime. You can easily slip a couple of isometric exercises into your workout and enjoy the benefits of dynamic and isometric training.
  • Isometrics can be a good alternative to dynamic movements when injury prevents a full range of motion

Limitations of isometrics training

Isometrics are best used as a supplement to regular training because they don’t provide the dynamic movements we use in everyday life and sport. Isometrics strengthen the muscles at specific joint angles, not throughout the whole range of movement. If replacing a workout with isometrics, try the exercises at multiple angles through the range of motion. Isometrics can also strain the cardiovascular system, which may make them unsuitable for people with high blood pressure. If you have a history of high blood pressure or haven’t had your blood pressure checked recently, check with your doctor before introducing isometrics into your training.