Paris: Justin Gatlin, the 2004 Olympic 100-metre gold medallist who was suspended between 2006-10 after failing a second drugs test but is currently dominating the world of sprinting, has been tested 59 times by the US anti-doping agency (USADA) since his return.

According to USADA figures released on Wednesday, Gatlin has already been tested nine times this season. In 2014, there were 15 tests, 14 in 2013, 13 in 2012 and eight in 2011. The tests were conducted both in and out of competition.

At the age of 33, Gatlin has this season set new personal records in both the 100m (9.74sec) and 200m (19.57sec), establishing himself as the favourite to usurp Jamaican star Usain Bolt at next month’s world championships in Beijing.

USADA did not specify whether the tests carried out on Gatlin involved urine or blood, and did not give any of the results, with the American not having been subject to any procedures.

After his suspension for use of testosterone, cut to four years from eight following cooperation with USADA, Gatlin officially returned to competition on August 3, 2010, with no testing carried out that season.

The 2005 double world sprint champion returned to win the 2012 world 60m indoor title, Olympic bronze at the London Games and a world silver in Moscow a year later.

It is not just USADA that conducts testing, Gatlin was also subject to exams by the World Anti-Doping Agency (WADA), national anti-doping bodies at international events, and even track and field’s governing body, the IAAF.

Before the London Olympics, every athlete underwent pre-competition blood testing.