Alexis Vastine first came to prominence internationally when he won a bronze medal at the 2004 World Junior Championships. He qualified for the 2008 Olympics with his performance at the 2007 Worlds. In Beijing Vastine lost a controversial semi-final decision to Manuel Díaz of the Dominican Republic, but Vastine earned a bronze medal. After winning a silver medal at the 2010 European Championships, he competed at the 2012 Olympics, losing out in the quarter-finals. Vastine was also a gold medalist at the 2005 Jeux de la Francophonie and at the 2009 Mediterranean Games.
In March 2015 Vastine was with a group of sports stars participating in the reality TV show “Dropped” in northwest Argentina. He was flying in a helicopter that collided with another chopper for the show, killing ten people, including Vastine and French Olympic swimming gold medalist Camille Muffat.