Collin Daniel Richards, also 22, has been charged with first-degree murder according to police.
"This is a tragic and senseless loss of a talented young woman and an acclaimed student athlete," said Iowa State University president Dr. Wendy Wintersteen in a statement.
"We mourn with her family and friends in Spain, her teammates here and all who knew her. On behalf of the entire Cyclone family, I extend our deep condolences to Celia's family and her many friends and teammates at Iowa State. We are deeply saddened."