If you train with weight, you may have noticed that it is more difficult to lift a weight than to keep it in the same position, and in the same way it is more difficult to keep it in this position than to lower it.
- Contracting muscle fibers under tension (such as when lifting a weight) is called concentric stress.
- Keeping the fibers contracted is called isometric stress.
- The extension of muscle fibers under tension is called eccentric effort.
As we have already said, concentric exercises allow you to use a greater weight. But how can we use this principle to increase our muscle gains? It’s simple. If you can no longer lift a weight, you will not be able to lower it. But if someone (or yourself) helps you with the concentric phase, you will be able to use more weight in the eccentric phase.
Let’s see some examples:
If you are exercising your lateral back muscles (latissimus dorsi) by lifting your own weight on a bar (as in the illustration) you may not be able to lift your weight after a few repetitions, especially if you are a beginner. This way you couldn’t benefit from the eccentric phase without help.
On the other hand, if after reaching the repetition in which you can no longer lift your own weight, you could get up with the help of a bench, or a chair. By having the final position of the exercise (up), you could lower yourself slowly and benefit from the additional strength that the eccentric exercise gives you.
Another example is the arm curl. If you sit on a bench and place the elbow of the arm that has the weight on the inside of your thigh, you could help with your other hand to lift the weight in the concentric phase (when you contract the muscle) and perform the eccentric phase ( lower the weight, only with the arm you are exercising, without the help of the other hand.
Another example could be the bench barbell lift (as in the main illustration in this article. If a person helps you by lifting the bar with you. You will be able to perform more repetitions by lowering it and reap the benefits of this type of exercise.
Several studies show that using more weight in eccentric exercise results in a stimulation of the muscle to adapt. In short, you will see greater muscle gains.
It is very important to remember that this is an advanced technique, without knowing exactly how much weight to lift you could injure your joints or tear a muscle or tendon.
Always start off light and build it up gradually. Remember that if you cannot perform slow, controlled movements you should be using less weight.