Her 43secs victory in the 5km run 20km bike 2.5km run was the fourth World Junior Duathlon title for the Team Bodyworks XTC club since 2001.
Sophie's win follows on from her European Duathlon title in 2007 and brings to a close a season that has reached both the highs and lows associated with sport.
Meanwhile in the penultimate World Cup Triathlon Series event of the 2008 season in Lorient, France Olly Freeman took a sixth place finish along with Todd Leckie. Team Bodyworks XTC team mate making his World Cup debut finishing in 14th place.
Todd's finish was one place behind GB Olympic Team athlete Tim Don. Olly has now moved his World ranking to a career high fifth with one race left in the season long series.
Team Bodyworks XTC athletes took part in the Littlehampton Development Chaser meet. The group of Alicia Buck, Emily Bignell, Sarah Ingle, Flora Alessondrani, Harrison Rolls King and Luke Howard posted 15 PBs between them on an intensive day of swims.
Meanwhile Josh Pankhurst was swimming for Sussex in Southampton winning the 100m Backstroke comfortably.
This followed on the back of the Brighton Ken Deeley Sprint Meet held the weekend before where the athletes took part over 50m on each stroke and 100m IM with individual event wins for Luke Stacey and Josh.