Sally Pearson says she would have risked the end of her athletics career by trying to overcome a hamstring injury and compete at the Rio Olympics.

The Olympic 100 metre hurdles champion says she's "gutted" at being forced to withdraw from the Rio Games after injuring a hamstring at training on Monday.

"I could have gone to the Olympics and still competed but competing and going out to the Olympics, it means different things to me," she told the Nine Network on Wednesday.

"I go there for 100 per cent effort and I wouldn't be able to give that effort that I would like to bring ... and the risk of re-injuring and causing a lot more damage and probably not coming back was very, very high.