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What are the 3 phases of Muscle Contraction? Eccentric, Isometric & Concentric Explained...

Have you ever wondered what those numbers on your training program actually mean? You see the words tempo and numbers '4-1-2', it just looks like a bit of code that only the coach truly understands right?

Well, the good news is it's actually a lot simpler than it looks. The 'tempo' or numbers, all they do is represent the time (in seconds) that you should spend in each phase of muscle contraction.

Before we go into detail about each phase of muscle contraction, we first must explain the basic function of a muscle, which again, is a lot simpler than you would imagine.

The main function of a muscle is to simply bring two points closer together. Every single muscle in your body has an origin and insertion, and each phase of contraction will control whether these points move closer or further away from each other.

Now you know that, we can dive into the detail of each phase of muscle contraction and what exactly each number in the 'tempo' column actually means:

CONCENTRIC: This is when the muscles shorten / contract. This is what most people think is a ‘contraction’. That is because this is the contraction tested for strength. The concentric phase of the lift is for example on the bench press when you are pushing the bar up. Surprisingly, this is the weakest type of contraction, this is why if you are testing your 1-Rep-Max on the Bench Press - you may be able to bring the bar down slowly but unable to push it back up. This is due to the Concentric phase being weaker than the downward (Eccentric) phase, bringing me on to the next contraction.

ISOMETRIC: This is the most uncommonly trained contraction but again is stronger than the most common concentric contraction. This is when the muscle doesn't lengthen or shorten during contraction it stays the same. This can be simply exercised by pausing and holding the weight in one place e.g pause squats.

ECCENTRIC: This is when the muscles lengthen during contraction, and arguably is the greatest phase of contraction for muscle hypertrophy. This is the downward phase of the bench press and is believed to be around 4x stronger than concentric contraction. This is the reason you can control heavy weight down to your chest on the bench but can’t push it back up. This can be trained by slowing down the eccentric phase of the lift during any exercise, therefore instead of dropping the weight straight after deadlifting the bar off the ground; slowly lower the bar back to the ground and you will gain more from it.

That's the basics for muscle contractions! Hopefully this free information will allow you to take your training up a level.

Don't forget, You can download FREE training programs directly from our website in a matter of seconds. Click the link for our homepage if you wanted to try something new for free.

Contact us if you have any questions regarding this article.

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