The number of local athletes who flunked drug tests in 2010 reached a five-year high, a report showed Tuesday.

According to the doping control center at the Korea Institute of Science and Technology, 43 athletes tested positive for banned substances last year.

There were 47 athletes who doped in 2005, but the number fell to 15 by 2008 and increased slightly to 26 in 2009, before nearly matching the 2005 level last year.

Bodybuilding was the most juiced sport with 18 athletes, followed by basketball with three.

The KIST said 39 were caught during competitions, while four tested positive in random tests outside competitions.

Of substances, diuretics were used in 17 cases, followed by steroids with 11 and stimulants with 10. Diuretics are known to help athletes lose weight and they can also be a masking agent for anabolic steroids or stimulants. In a high-profile case, middleweight boxer Julio Cesar Chavez Jr. of Mexico tested positive for a diuretic.

Daiane dos Santos of Brazil, the 2003 world champion in artistic gymnastics, and the 2001 world rhythmic gymnastics champion Alina Kabaeva of Russia have tested positive for diuretics, too.

Officials have stepped up their anti-doping drive in local sports. The KIST said there were 4,139 drug tests last year, compared to only 599 in 2001. 

(Yonhap News)