Isotension

No doubt you’ve heard about Isotension. But you may be wondering – how does it apply to your workouts? Building mass is one thing — but what about carving out that competition physique or summer beach body? You have your nutrition dialed in, cardio set, and you’re going for it.Yet you want sharper definition and better separation. The answer might be isotension. The term might make it sound more involved than it really is. It’s a simple technique, and it has been around for decades. With that in mind, let’s dive in and find out more!

What Is Isotension?

Isotension was popularized by legendary guys like Frank Zane, Arnold, and other top guys from that era. It means maintaining continuous contraction of a muscle — either by practicing posing or by holding a static squeeze at the top of a rep. This drives blood into the working muscle and improves vascularity and definition. It also enhances the mind–muscle connection. Many pro bodybuilders (and weekend warriors) use isotension because it helps them achieve good muscle separation.

Joe Weider and Isotension – Historically Important

It should be noted that back in the “golden era” of bodybuilding, this was a “Weider Principle”. Back then, Weider made it seem like he came up with all of his principles, and he did a good marketing job by tying everything related to bodybuilding to his name. However, that didn’t last forever. 

As far as his “Principles” are concerned, he did not invent them but observed them being used by the top guys of the 40’s, 50’s and 60’s. He then categorized them and marketed them under his name. The good thing  about it is the fact that you can find a lot of useful tips within his “Principles”. (1)

Isotension Helps Bring Out The Details

If you’ve never tried it, isotension can bring a noticeable change in muscle detail and separation. After a workout, your muscles are fatigued and nutrient-depleted. No doubt you’ve stood in front of a mirror post-workout and flexed. Have you noticed how certain muscles pop more than others? Isotension makes that happen. 

So, Is It Just Flexing?

No, not exactly. Flexing casually in the mirror is one thing. You aren’t holding the poses long, and really you’re just checking out the muscles you just trained. Isotension, on the other hand, is an intentional, targeted contraction that you hold for 20-30 seconds. You’re applying maximum effort to squeeze a specific muscle, and you’re doing it multiple times.

If you have ever flexed your biceps and noticed that they look fuller and more vascular, that’s the effect of isotension. When you use it regularly, it can also support your muscle control, and help you achieve that carved look you see in the pics of bodybuilders in great shape.

When Should You Use Isotension?

You can use this classic principle anytime and almost anywhere. Sitting at a desk at work? Tense and squeeze your calves. Driving? Try tensing your chest or triceps. Lifting a box? Use the time to squeeze your biceps and lats. Additionally one of the best times to use isotension is between sets during your workout. You can also use it post-workout, or in a separate session devoted solely to trying this technique out.

How To Use Isotension

We’ve talked about using it during your day. As far as your workout, use it like this: after a set, perform a targeted hold on the muscle you just trained for 10–15 seconds. Your muscle is already full of blood from the set, so the added squeeze amplifies the pump. Do this  between each set. 

Summary

Competitive bodybuilders practice their poses for hours, often holding the pose for as long as possible. In fact, the night before the 1980 Mr. Olympia, Arnold was waterlogged from a cortisone shot for his shoulder. He says he stayed up most of the night hitting and holding his poses to flush the water out (maybe he should have shopped illpumpyouup.com for a diuretic, had we been around back then!). No matter when you use it, you can borrow the concept of isotension to help you turn your hard-earned mass into a detailed physique that stands out from the crowd! 

References:

1. https://www.tigerfitness.com/blogs/training/the-weider-principles-a-complete-analysis#:~:text=While%20these%20principles%20have%20been,one%20of%20the%20following%20categories: