"National Physical Fitness Day" is usually ZIM's (and Dib's) least favorite day. But this year, President Man will be coming to Skool to congratulate the winners! IN PERSON! And ZIM must be one of those winners, so he can kidnap President Man! Thus begins THE BULKENING. Of course, Dib figures out what's going on, and in this case, the only way to defeat ZIM... IS TO GET PHYSICAL.