Concentric And Eccentric

Any complete movement of an exercise is known as a rep. If you do so many reps this is called a set. If for example you lift a dumbbell 15 times, have a brief rest and then continue again, have a brief rest, and then lift one more time, this would be 3 sets of 15 reps.

When lifting a dumbbell up and down there are three phases.

The first phase is when you lift the dumbbell up. It is known as the concentric contraction. The working muscle shortens, pulling the bones on either side of the joint being used closer together.

The second phase is known as the transition. You are moving from lifting the dumbbell up to putting it down. It is important that you don't release the weight through the transition and that you don't hold back on the strength you used when lifting the weight. This is so you get maximum effect from the movement and don't injure yourself in the process.

The third phase where you let the dumbbell down slowly is known as the eccentric contraction. As you lower a dumbbell during a curl, for example, the biceps lengthen, even though it's still contracted to some degree. You should never simply let the weight drop down.

If you hear someone at the gym calling out loudly and/or crashing the weight down, this is most likely that they simply aren't strong enough to hold the weight adequately. These type of people are generally wannabe bodybuilders who simply don't have the knowledge or tempered ego to do the exercise in a correct and controlled manner.

There is the occasional view that you should work your muscles to failure when lifting weights. This involves working your muscles really hard and pushing that final weight as hard as you can so that the muscle has essentially maxed out. I am not an expert on human anatomy, however this method of lifting weights is not something I personally subscribe to. I believe in having control in appropriate exercises that you do.

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