In this question, it seems to be discussing the difference between dynamic and static muscle actions.
1. Dynamic muscle action involves motion, which means the muscle is actively moving a body part. An example of dynamic muscle action is when you lift your arm to wave hello. Your muscles are actively engaging to produce that motion.
2. Static muscle action, on the other hand, does not involve motion. It typically refers to a muscle contraction without changing the length of the muscle. An example of static muscle action is holding a yoga pose like the plank position. Your muscles are engaged and working, but there is no movement happening.
So, based on the options provided:
- Motion would be associated with dynamic muscle action.
- A stretch could be related to dynamic muscle action as well, depending on the context. For example, when you stretch a muscle to reach for something, it involves dynamic action.
- None of the above would likely refer to static muscle action because in that case, there would be no motion or stretching involved.
Therefore, in the context of muscle action:
- Dynamic involves motion.
- Static does not involve motion.
