Question

When muscles are first overloaded during training, muscle soreness occurs from which action?

a. Static muscle action
b. Concentric muscle action
c. Eccentric muscle action
d. Isometric muscle action
e. a and d

Answer 1

Muscle soreness after training is primarily caused by eccentric muscle action, where muscles lengthen under tension, potentially leading to microscopic damage and resulting in delayed onset muscle soreness (DOMS).

Step-by-step explanation:

When muscles are first overloaded during training, muscle soreness occurs predominantly from eccentric muscle action. This type of action refers to when a muscle is lengthening under load. An example of eccentric muscle action is when lowering a hand weight in a slow and controlled manner. During this process, the muscle is still under tension, but the amount of active cross-bridges is decreasing as the muscle elongates, which can lead to microscopic damage in the muscle fibers and contribute to delayed onset muscle soreness (DOMS). This is contrasted with concentric contractions, where the muscle shortens to move a load and typically induces less soreness.