(Reuters) - Double Olympic champion Valerie Adams feels the suspension on Russian athletes from the Rio Games is a positive step toward eradicating doping and the New Zealand shot putter has called for a life ban on drug cheats.

Russia's track and field team have been suspended from international competition since November following a World Anti-Doping Agency report and are barred from next month's Games as a punishment for the nation's systematic doping problems.

A number of Russian athletes have appealed against the International Association of Athletics Federations (IAAF) ban, and the Court of Arbitration for Sport (CAS) will step in to settle the dispute between the country, its athletes and the governing body of world athletics.

"It will definitely be a positive step because if you don't stop it at the top it will just keep going," Adams, 31, told the Guardian in an interview.

Adams, who was awarded gold at the 2012 Olympics after Belarusian Nadzeya Ostapchuk tested positive for a performance enhancing drug, said there should be no way back for tainted athletes.

"Once a cheater always a cheater. Kick them out and don't let them back in. Zero tolerance," she said.

Adams has thrice suffered heartbreak in her career, after finishing behind athletes who have subsequently been found out as drug cheats.

"In 2004, at the Athens Olympics, I finished ninth (behind winner Irina Korzhanenko of Russia, subsequently convicted of doping at those Games) and so I missed out on three extra throws (granted to the top eight competitors)," Adams said.

"In 2005 Nadzeya Ostapchuk got the world championship gold ahead of me but then, eight years later, they re-tested her results and she got caught for doping. Same thing happened in 2012 at the London Olympics."

Adams said doping violations has tarnished her sport.

"This whole situation with doping right now is damaging to our sport," she said. "It fires me up to educate our young athletes and make them understand it is possible to become a champion without using illegal substances.

"That's so important because it ruins your life. You've worked so hard for what? You get caught and then what? To win something because of a lie?"

Should she win a gold in Rio, Adams will become the first woman to win the shot put event at three successive Olympics.

(Reporting by Nivedita Shankar in Bengaluru; editing by Sudipto Ganguly)