Vincent Leroyer, 61, spoke of his "very sincere and very deep shame for the acts I imposed" on the victims, who were aged six to 14 at the time.
Leroyer, who was on the second day of his trial in the southwest city of Bordeaux, acknowledges nearly all of the accusations leveled against him by five men in their thirties or forties who have struggled with addiction and other difficulties since they suffered a catalogue of sexual abuse at his hands as children and adolescents.
Leroyer faces up to 20 years imprisonment if convicted of child rape and 10 years for sexual molestation. The jury's verdict is expected on Wednesday.
A French national backstroke champion in the 1970s, Leroyer then managed the Rouen Hockey Club from 1986 to 1996. That prestigious role during a period that saw the club win five national championships helped him befriend the parents of his child victims, who often accepted him into their homes and lives.