Rory McIlroy says golf must improve its drug-testing regime as he could "get away with" doping as it stands.
The most recent report from the World Anti-Doping Agency revealed 507 tests were carried out on golfers in 2014, with eight testing positive.
"I've been tested once this year but it was only a urine test," said the Northern Irish world number four.
"You can't really pick up HGH (human growth hormone) in a urine test, so I could use HGH and get away with it."
The 27-year-old added: "If golf is in the Olympics it needs to improve the drug testing.
"On average, we get tested four or five times a year. It's very little compared to other Olympic sports." The International Golf Federation, which is responsible for the testing programme, has not commented.
Wada carried out 283,304 tests worldwide, with banned substances found in more than 3,800 samples.
Golf had the fewest number of tests done out of all the summer Olympic sports.