There are different types of contractions that happen in our muscles depending on the type of actions we do. Our muscles need to contract differently when we pick-up a box, when we are carrying a box, and when we set a box down. Three different types of contractions happen in the same muscle in these three situations. In this post, I'll share a bit about these three types of muscle contractions.
Types of Muscle Contractions
There are three types of contractions each muscle can undergo -
- Concentric muscle contraction
- Eccentric muscle contraction
- Isometric muscle contraction
Concentric muscle contraction
Concentric muscle contraction is a type of muscle activity where the muscle
fibres shorten to create power in the muscle. This mostly happens when the
muscles shorten and a weight provides resistance to the muscle, like when we
lift a box from the floor. During this type of contraction the joints are
pulled in the direction of the muscle.
When people exercise, this is the most common type of contraction that their
muscles undergo. This type of contraction helps to increase the muscle mass
(the number of muscle fibres in a muscle). Some examples of concentric muscle
contraction are bicep curls, standing up from a squat, extending from a
pushup, crunches/sit-ups etc.
Eccentric muscle contraction
Eccentric muscle contraction is a type of muscle activity where the muscle
fibres extend to create power in the muscle. These type of contractions happen
when the muscle extends due to an external force that is more than the power
the muscle generated. During this type of contraction the joints are pulled
away from the muscle. An example of this is the contraction our arm muscles go
through when we set down our heavy grocery bags.
This type of contraction also helps to increase the muscle mass (the number
of muscle fibres in a muscle). Some examples of eccentric muscle contraction
are lowering a dumbbell (opposite of bicep curls), tricep extensions,
squats, lowering from calf raises etc.
Isometric muscle contraction
Isometric muscle contraction is a type of muscle movement in which the length
of the muscle remains the same but the power in the muscle increases. In this
type of contraction, the muscles are activated but the joints don't move. An
example is, after we lift a box (concentric) and before we set it down
(eccentric), when we are carrying a heavy box somewhere, our biceps are having
an isometric contraction. During this type of contraction, the tension applied
to our muscle stays the same and it does not exceed or reduce below the weight
of the object we are carrying.
Some examples of isometric muscle contraction are planks, bridge holds, wall
sits etc.
When we exercise we should understand how each of the exercises we do contract
our muscles, and how they help us build and maintain healthy muscle mass and
strength.
Stay healthy and enjoy finding joy in health!