Yannick Agnel started swimming at the age of eight, with Nautic Club Nîmois. He made a name for himself in 2009, during the French Championships. At the time, the full length swimsuit was at the heart of many debates, but nevertheless allowed. All the other swimmers wore one except Yannick, who decided to swim in an ordinary pair of swimming trunks. In 2010, he became European Champion of the 400m freestyle. Yannick also became French Champion of the 200m and 400m freestyle in 2011 and French Champion of the 100m and 200m freestyle in 2012, where he earned his ticket to the Olympics.
Yannick took on international status during the London Olympics, where he became Olympic Champion of the 200m freestyle and the 4x100m relay, also winning silver for the 4x200m freestyle. He confirmed his leadership status in 2013 during the Barcelona World Championships, winning the world champion title for the 200m freestyle and 4x100m freestyle. Following these achievements, Yannick set himself a new challenge - to move to Baltimore in the US and work with Michael Phelps’ coach, Bob Bowman. Finally back in France in 2014, swimming with the Club Olympique in Mulhouse, he decided to call upon the talents of Coach Lionel Horter.