International Sports Sciences Association (ISSA) Trainer Practice Exam

In a concentric contraction, what happens to the muscle?

1. The muscle shortens

2. The muscle lengthens

3. The muscle stays the same length

4. The muscle relaxes

The correct answer is: The muscle shortens

In a concentric contraction, the muscle shortens while generating force. This type of contraction occurs when the muscle fibers contract and pull on the bones, which leads to movement at the joint. For instance, during a bicep curl, as you lift the weight towards your shoulder, your bicep muscle shortens to create that upward motion. This shortening allows the muscle to overcome the load being lifted, facilitating movement against resistance. Understanding this fundamental concept is crucial as it applies to various exercises and training protocols, particularly in resistance training and physical rehabilitation.