Small actions are fine. If there is a problem, for ones such as walking somewhere, then in your next post you can say your character stopped after a moment of thought. That's not a problem and are things you can rectify with your next post. Small actions keep the story flowing, and reduces the need for the next person to take a moment to say yes, when the first person would have done it for them.

Big actions? Decisions(Fight or flight)? Things out of a characters personality? Then that's when its a problem.