That is the Wine and Dine race weekend, with a 5K on Friday at Animal Kingdom, a 10K on Saturday morning, and a half marathon on Sunday morning. The races do not really impact park touring, as the 5/10K races are done and out of the parks prior to opening, and the half marathon finishes at EPCOT by 10:30 or so. There are some road closures on Sunday morning that really only impact getting into Epcot early morning. There is a race party at Epcot Sunday night after park closure, so it will be moderatly more busy that evening as party guests can get in as early as 8:00. This should not really be an impediment to you planning on going.