Isometric exercises arose powerfully in the world of physical culture with the rise of Alexander Zass, but isometrics themselves have been a part of physical training for centuries.

Isometric exercises have been a staple in the strength training regimen of martial artists for centuries. Karatekas practice sanchin with a vengeance and the Shaolin stances build leg power unlike youíve ever seen.But to some extent, thatís not isometrics, not like itís best used today anyways. I like to think of the martial arts style, the style that allows monks to hold stances for hours as though seated, as passive isometrics, whereas the strength training style, the style that enabled Alexander Zass to bend steel like putty, is active isometrics.

A major goal of many martial artists is to release incredible force through total relaxation. Letís take, for instance, the most widely known stance, the mabu, or horse stance.

In the stance, you want to eliminate all tension in your legs to hold the stance as long as you can. This builds internal power in the legs steadily, until after years of continued practice, you reach a high level of strength and relaxation in the stance.

I use the word passive lightly, because that suggests that there is no action in the stance, which isn't the case. In fact, because the nature of the stance is relaxation, it recruits immense mental power and concentration, which is far from passive. It is this mental concentration that's thought to help build internal power.

The nature of its passivity lies in the lack of tension. With active isometrics, tension is key, and the higher amount of tension you can produce, the quicker you can fatigue your muscles and get faster results. The two look the same, but the nature of the exercise is very different.
Letís take one of the most widely known isometric holds for example, the plank. The plank is a strong core exercise with the potential to truly build abs of steel.

However, thatís only if youíre doing the exercise in an active isometrics style. Most people view the plank purely as a hold for time, while putting little to no tension into the movement.

Save that for Pilates class. I personally donít time my planks; instead, I get into plank position and approach the hold as a sort of crunch. Rather than simply holding the plank, Iím trying to bring my toes to my torso as you would in a V-sit.

My whole body is shaking within seconds from the tension that Iím putting into the movement, rather than simply holding the plank.

Another example would be the wall sit, where you put your back against a wall and lower yourself until your legs are parallel to the ground in a sitting position. I dislike the term ďwall sitĒ because it suggests that the hold is passive, as though trying to sit in a chair.

The best way to get the fastest leg results from a wall sit is to try and drive your feet into the ground as you would with a squat.

You should be constantly driving your heels into the earth as you are in the hold, and youíll feel the burn quickly. Your muscles should fatigue in a few tense seconds, and you should be gaining fast, incredible strength from the movement.

An isometric hold should never just be a hold. If your hold is passive, you can surely build strength in your movements, but it will take years of dedicated practice; in a world where people are searching for the fastest results, this style will offer no real benefit outside of a Pilates class.

If you want real world strength and results quickly, I mean within weeks, you should do active isometrics and preferably maximum tension.

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