His name was Koroibos,  and apparently he won the “stadion”, a 192 meter race, which was the only event at the 776BC Olympics.

If you consider the importance of carbohydrates for athletic performance, this makes a lot of sense, as he probably had more access to carbohydrates compared to anyone else at that time. So, I guess you could say it’s evidence of carbohydrate loading in ancient times.

—I learned about this fact from: http://www.topendsports.com/nutrition/olympic-ancient.htm and http://en.wikipedia.org/wiki/Coroebus_of_Elis