Question

Poor blood circulation will likely reduce the contraction power of a person's

Answer 1

Poor blood circulation would cause a reduction in the contraction power of the blood vessels. These blood vessels are responsible for pumping blood to the organs of the body and it's extremities. When there is an obstruction in these blood vessels, it would lead to a condition know as low blood pressure.

Answer 2

Poor blood circulation will likely reduce the contraction power of a person's myosin.

Myosins are motor proteins and they play a major role in muscle contraction and in a wide range of other motility processes in eukaryotes.
They depend on the ATP and are also responsible for actin-based motility.
They are also used to produce mechanical energy that is used in various body functions such as muscle movement and contraction.