MENOMONIE, Wis. -

Ten Menomonie High School football players have been suspended for the first three games of the season for drinking an energy drink that contains a banned substance.

Athletic Director Bart Boettcher said the athletes did not know the drink C4 Extreme contained Synephrine, a stimulant banned by the Wisconsin Interscholastic Athletic Association. The players said they purchased the drinks at an Eau Claire GNC supplement store.

Superintendent Chris Stratton said the district's athletic code calls for a three-game suspension for a player who admits to using a substance banned by the WIAA.

WIAA Deputy Director Wade Labecki said performance-enhancing substances can provide an unfair competitive edge and cause health problems.

The label on C4 Extreme said it shouldn't be consumed by anyone under 18. None of the student-athletes were 18.