Superfit Jennifer Lopez has aced her first triathlon, finishing the gruelling event in Malibu, California in under two and a half hours. The singer was cheered on by husband Marc Anthony as she ran, swam and cycled her way through the endurance race on Sunday. But the uber-glam singer and actress shed her wetsuit and goggles in time for hubby Marc Anthony’s surprise 40th birthday party later the same night. Phew…. JLo wasn’t the only celeb to get a piece of the action. She was joined by actor and Maid In Manhatten co-star, Matthew McConaughey, who also took part. He was watched and cheered on by girlfriend Camila Alves and their baby son Levi. La Lopez, 39, competed to raise money for Children's Hospital Los Angeles and to make children Max and Emme proud. We’re sure they will be.