With my younger classes, I repeat throughout the year. I'll teach throwing at the beginning, middle and end of the year. I'll repeat lessons they enjoy and know how to do as well as new ones tossed in there.

I don't see a problem with repeating lessons either, in fact with my K-1st grade I usually do some kind of skill or activity involving locomotor skills once a month. With my older students we will usually replay a favorite game in between units, we do this as a nice transition.

My major question to you would be: Why are you repeating it?

I agree with other posts that say if you have some time between units, because you finished early, then play some games that the students enjoy, get them active, and reinforce other skills and concepts. Or, if it is a major concept that they need to master, then periodically reinforcing it is a good idea. These situations might involve repeating the same game multiple times. If you are repeating it because they did not master the skill or concept, that would be fine too. They obviously need to some more practice with that.

However, I disagree with repeating things simply because the students enjoy it. We need to get away from the mindset of, "Keep them busy, let them have fun, and they'll be good." But, if they need to review a game, skill, strategy, and/or concept, then it might be easier to pick a game they know and enjoy, that way you can spend your time talking and discussing what you want to see in terms of skills and strategies and not discussing the game, because they would already know the game.