Kaepernick rips into “illiterate or ignorant” heckler on Twitter

Robert Griffin III isn’t the only NFL quarterback who spars with fans on social media. Colin Kaepernick got into a Twitter battle with a fan today over the fan’s reaction to Kaepernick’s description of the work he put in today. Kaepernick tweeted that today he did “1000 abs…. arm workout….. 10 min straight on the…