You're both feeling confident and energetic when you get together during these few months -- perhaps a little too much so. When you go out for a run together, you might push each other a little too hard and both end up with strained muscles the next day. When you play a friendly game of Scrabble together, you might get a little too competitive -- all in fun, of course, until you end up more and more annoyed with each other the further the game progresses.
You're bringing out each other's competitive spirit, which isn't a bad thing in itself; the bad part comes when neither one of you knows when to pull back. You may get into arguments as a result of this tricky energy; you could even end up ticking off your friends in a social situation, creating a problem that will need fixing before you can all relax around each other again and have a good time. Watch yourselves when you're hanging out in a social group, because the tendency is all too strong now to be arrogant and obnoxious. And when you're exercising or playing games together, remember that it's all in fun. There's no reason to treat the stakes as life or death!