Velilla began her career in 1998 and quickly rose to prominence in the Spanish sprinting scene. She won her first national title in the 100 meters in 2000 and has since claimed 11 additional Spanish titles in various individual and relay events.
On the international stage, Velilla has represented Spain in numerous major competitions, including the Olympic Games, the World Championships, and the European Championships. Her greatest achievement came at the 2007 European Athletics Indoor Championships, where she captured the gold medal in the 60-meter dash. Velilla also won a silver medal in the 100 meters at the 2009 Mediterranean Games.
In addition to her athletic achievements, Velilla has also been involved in various sports-related initiatives, including promoting physical activity and advocating for greater gender equality in sports. She is a motivational speaker and has frequently been featured in media and educational programs.