Bertrand Russell wasn't very keen on ancient philosophy and I doubt he took Aristotle's solution to Zeno's question on what constitutes motion.
Bertrands assertion is at odds with Aristotle - for he says that if the collection is infinite, then they can be passed if they are potential but not if they are actual. I would suggest that Russell was rekying upon the theory of inginite series.
This is most common solution to Zeno's question, that is to use infinite series. Now, although there was no such thing as infinite series in Aristotle's time, it is clear from his discussion that they were understood qualitatively, if not formally, and he says that they are an 'adequate' answer but not the true answer.
For the latter, he uses his theory of potentiality and actuality and says that motion is an alternation of potential motion with actual motion; potential motion is becoming and changeful but not actual; whilst actual motion is not in fact motion, it is not changeful, but rest.
Interestingly, just like Parmenides he says that which is actual does not move. As Zeno was supporting Parmenides, in some sense he is verifying both Zeno & Parmenides.
It's also worth noting that Hegel supported Aristotle. He said that the reason why something moved is because it is both here and there - a sort of super-position.
Moreover, it should be noted the close analogy between Aristotles conception of motion and quantum evolution. In quantum mechanics, the quantum potential evolves and is not real whilst the the quantum reduction does not change but is real. Notice that the quantum potential is both here and there - just as Hegel suggested.