Muscular System Lesson 4 Muscle Contraction

Question 1

What is a concentric contraction?

Answer 1

When a muscle contracts and shortens it is called a concentric contraction. Concentric contractions are common in power sports or sports where you need explosive sports. Power sports such as weight lifting and explosive sports such as 100m sprinter.
They cause movement at the joint, as the force exerted by the muscle is greater than the resistance.

Question 2

What is an Eccentric contraction?

Answer 2

When a muscle contracts it can also lengthens under a load or tension. This is often when the muscle is working against gravity, trying to control a movement.

For example when the quadriceps contract eccentrically during the downward phase of the squat. When you are lifting a bar in the gym, the triceps are contracting but lengthening; therefore they are working eccentrically.

Question 3

What is Isometric contraction?

Answer 3

This is when there is little or no movement in the muscle or joint. Also the muscle doesn’t shorten or lengthen.

For example when you are in the cross position in gymnastics, when you are on the rings. The muscles are working but there is no movement.