After closing with a 62 at the Tournament of Champions this month, Chris Kirk showed up at the site of his next start and learned he had been randomly selected for out-of-competition testing as part of the PGA Tour's anti-doping program.

The timing prompted Kirk, tongue in cheek, to post on Twitter: “Like clockwork, tie course record on Monday, drug test on Wednesday.”

On Saturday, after his round at the Humana Challenge in La Quinta, Calif., Kirk said he was happy with “any and all drug testing.” All golfers with gold medal aspirations should feel that way, because the anti-doping program they are set to join is considerably less predictable and more invasive.

In advance of golf’s return to the Olympics next year in Rio de Janeiro, the golfers will be under the aegis of the World Anti-Doping Agency. The agency operates its testing program much differently from what golfers, especially those from the United States, have come to expect. Consider Kirk, whose first exposure to drug testing, he said, was during his freshman year at Georgia. Describing the N.C.A.A. protocol, he said, “They’d notify you the afternoon before, and you had to be there the next morning at 6 a.m. to give a sample.”

Kirk graduated to the program on the PGA Tour, in which players are targeted at tour sites. If they give urine samples on the Monday, Tuesday or Wednesday of a normal tournament week, that is considered out-of-competition testing.

Once under the Olympic umbrella, the golfers will be subject to unannounced testing at any time, including their off weeks. Brandt Snedeker, who has been critical of the tour’s anti-doping program, said: “The tour used to say they’d do that. It never really came to fruition.”

Speaking after his Saturday round at the Humana Challenge, Snedeker added, “I think it’s something that every golfer is going to be a little shocked when it actually does happen.”

As part of the Olympic anti-doping program, golfers will have to provide the anti-doping agency with a daily one-hour window of availability, listing when and where drug testers can find them, no matter where in the world they happen to be. In addition to urine, blood samples can also be collected.

“It’s going to be different,” Graeme McDowell said, “having the drug police knocking on your door at half five in the morning.”

McDowell, who is poised to represent Ireland at next year's Olympics, was speaking from last week's PGA Merchandise Show in Orlando, Fla. He appeared Wednesday on an Olympics forum alongside Suzann Pettersen, a top performer on the L.P.G.A. Tour; Gil Hanse and Amy Alcott, the architects of the 2016 Olympic course; and Peter Dawson, the International Golf Federation president.

Pettersen, 33, who is from Norway, said she was unfazed by the prospect of more stringent drug testing. She said she had to submit to regular and random drug testing from her national federation when she was a teenager.

“The procedure that we’re facing is nothing compared to my fellow Norwegian athletes,” she said. “They have to report their whereabouts 24/7, and if you’re not at the spot you said you were going to be, that’s almost the same as failing a drug test.”

From her perspective, the more stringent testing for the world’s golfers cannot start soon enough. “I know some of the Swedish athletes have joked and said, ‘Why don’t you install a GPS in us, and you’ll know where we are all the time?’ ” she said. “The pressure of always being on top of your schedule can be a pain, but for me, clean sport has always been a top priority.”

When will the golfers become subject to the anti-doping agency’s testing policies? McDowell said it was his understanding that it would be during the 13-week period leading up to the Olympics, which are scheduled to start on August 5th of next year. He was echoing the time frame set forth by Dawson, who said the golfers would be under the agency’s umbrella starting three months before the Olympics. “I think that’s it,” he said.

According to an official with the United States Anti-Doping Agency, pro athletes historically enter the registered testing pool 12 months before the Olympics, and the plans being completed for golf follow that timetable.

The prevailing view in golf is that drug testing is unnecessary because it is a clean sport whose practitioners consider cheating abhorrent. Speaking for that majority, Snedeker said: “I want the playing field level. I just think in the other sports, there’s so much to be gained by doing P.E.D.s,” or performance-enhancing drugs.

He added: “I get it when you’re talking about a hundredth of a second being the difference between winning an Olympic medal and not winning an Olympic medal. But with golf, I still remain skeptical.”

Ask most golfers why athletes take performance-enhancing drugs, and they will say it is to add muscle. But the drugs can also be used to help athletes recover faster from heavy training or injuries, as the players were reminded recently when one of their own on the Web.com Tour, the Class AAA of golf, received a one-year suspension for violating the PGA Tour’s anti-doping policy. That golfer, Bhavik Patel, a native Californian who played for Fresno State, did not appeal his punishment. “In an effort to overcome an injury, I made a lapse of judgment,” he said.

McDowell said it was important for those in golf to take the Olympic anti-doping program seriously. “It’s going to be very insightful for us as a sport, as a game, as professional athletes, to experience what those other sports have to put up with,” he said. “I’m not going to say we’ll embrace it. We will accept it.”

He added: “Part of the whole growing process to become an Olympic sport was to step up to the plate and really be responsible professional athletes and toe the line. We shouldn’t have anything to hide, and that’s the bottom line.”

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