Final answer:
The question does not provide enough context to determine the theoretical upper limit to muscle contraction speed. Muscle contraction times vary, with fast-twitch fibers contracting quickly and cardiac muscle having longer refractory periods. The muscle contraction speed can also be modulated by the nervous system.
Step-by-step explanation:
The theoretical upper limit to how fast a muscle can contract is not specified exactly among the options provided. Muscle contraction times vary depending on the type of muscle fiber involved and the function it performs. For example, fast-twitch muscle fibers, like those predominant in a professional sprinter, contract quickly, but the exact time is not universally fixed and can be subject to individual variation. The heart's cardiac contractile muscle, on the other hand, has a longer absolute and relative refractory period totaling approximately 250 milliseconds to ensure proper blood pumping without premature contractions that could be life-threatening. The speed of muscle contraction can be influenced by neural input from the central or somatic nervous system as local conditions dictate.