Using Different Types of Muscle Contraction for Strength Training Workouts

I answer a lot of fitness questions during each session and I glean tremendous value from the conversations I have with clients about fitness. Conversing with them allows me to develop a better understanding of how different people with different results view exercise and fitness results.

One of the questions I was asked by a client new to strength training workouts was: “Why do I need to control the weight when I’m lowering it?”

While it seems like a simple question, I started to wonder if there were some, or even quite a few people who don’t know the difference between or the value of different types of muscle contractions. I thought I’d create a post with some insight.

There are three different types of active muscle contractions: concentric, eccentric, and isometric. As you read on, take note that the word contraction, which implies shortening, actually refers to an action that generates tension within the muscle and causes it to perform work. Muscle contraction (work) can be performed during the shortening, lengthening, or static tension of the muscle.

Concentric Muscle Contraction: Muscle Actively Shortening
Example: Lifting a dumbbell upwards during a bicep curl

“When a muscle is activated and required to lift a load which is less than the maximum tetanic tension it can generate, the muscle begins to shorten. Contractions that permit the muscle to shorten are referred to as concentric contractions.” [1]

Eccentric Muscle Contraction: Muscle Actively Lengthening
Example: Lowering a dumbbell down during a bicep curl

“During normal activity, muscles are often active while they are lengthening. As the load on the muscle increases, it finally reaches a point where the external force on the muscle is greater than the force that the muscle can generate. Thus even though the muscle may be fully activated, it is forced to lengthen due to the high external load. This is referred to as an eccentric contraction (please remember that contraction in this context does not necessarily imply shortening).”[1]

NOTE: “muscle strengthening may be greatest using exercises that involve eccentric contractions.”[1]

Isometric Muscle Contraction: Muscle Statically Contracting
Example: Holding a dumbbell half-way up during a bicep curl

“A third type of muscle contraction, isometric contraction, is one in which the muscle is activated, but instead of being allowed to lengthen or shorten, it is held at a constant length.”[1]

As you can see by the definitions listed above, the purpose of controlling the weight as you lower it, is to maximize the eccentric muscle contraction. According to references used for this article, maximizing the eccentric portion of the contraction will cause you to develop maximum strength in the target muscle group.

Try this example of a shoulder strength training workout circuit which includes all three types of muscle contractions. Perform all three exercises in succession with a rest period at the end then repeat for a total of 3 sets. Let me know what you think!

Exercise 1 & 2:
1)Seated shoulder press, alternate arms during press
2)Stand and hold weights statically overhead with perfect posture for 1 minute (no squirming!)