Career
He became a stagiaire for Cofidis in 2003 before turning professional with the Vlaanderen–T Interim team in 2004. At this stage he was specialized in the cyclo-cross discipline but was beginning to perform well in stage races such as the Deutschland Tour. In the 2006 Giro d"Italia Gadret showed great potential in the mountains by finishing 7th, 6th and 5th on the three mountain stages.
He crashed on the 18th stage and was forced to abandon with a broken collar bone.
Despite these promising results on the road, Gadret was back in the 2006–2007 cyclo-cross season where he challenged the domination of Belgian Sven Nys in the Koppenbergcross and finished 8th in the UCI World Cyclo-cross Championships. Returning to the road with the aim of competing in his first Tour de France, Gadret took his first road victory at the Grand Prix of Aargau Canton.
On Stage 15 of the 2010 Tour de France Gadret caused controversy when he refused to give his wheel to his team leader, Nicolas Roche, following a puncture on the final climb of the day and then began attacking the group ahead of Roche. He later finished 19th overall In the 2011 Giro d"Italia, Gadret finished 3rd overall with a victory on stage 11.
After eight seasons with Ag2r–Louisiana Mondiale, Gadret left the squad at the end of the 2013 season, and joined the Movistar Team for 2014.
He retired at the end of 2015. Cyclo-Cross.