Commonly, when I describe a person moving with speed in the past tense, I would say, "He moved quickly. He was fast to react." Of the 3 words, I would recommend using "quick" more in the present tense with people like, "move quickly now folks. Quickly quickly people!" There are examples of using "rapid" to describe people but generally I hear "rapid" used to describe objects more than people. "There's been RAPID growth in the number of new businesses in the town." "Scientists are concerned about the rapid disappearance of the island's coral reefs." http://www.merriam-webster.com/dictionary/rapid

These words are interchangeable