Jessica Ennis-Hill insists there is no chance of her continuing her career beyond the 2017 World Championships in London.
The Olympic heptathlon champion is building up to the defence of her title in Rio and admits she could hang up her spikes after August's event in Brazil.
"I think at the moment I'm just focused on Rio and being the best prepared I can and going out there and seeing what I can do," said the 30-year-old, who is recovering from an Achilles injury which ruled her out of the indoor season.
"And then it's going to be a decision to make after Rio for me - whether I decide to retire after Rio or whether I decide I want to do one more year and go to the World Championships and retire after that. But I definitely won't be going on any longer than 2017."
The Sheffield athlete will head to Rio as the reigning world champion after her astonishing comeback victory in Beijing last summer when she took gold in only her second heptathlon since London 2012 and just 13 months after the birth of her son Reggie.
But she maintains she will not be favourite to land another Olympic crown.
Ennis-Hill, whose Beijing s uccess saw her nominated for the 2 016 Laureus World Comeback of the Year Award, added on Laureus.com: "People will obviously expect me to just keep performing at a high level and winning gold medals.
"Unfortunately it's not that easy. And this year is going to be more challenging just because of the level of competition. Everyone has stepped up their game.
"It's going to be tough and I think I'm definitely not the favourite. I think there's Brianne Theisen-Eaton (the Canadian who won pentathlon gold at the World Indoor Championships this month) and I think Katarina Johnson-Thompson - she had her disappointments last year - is going to want to come back and make amends for what happened in Beijing."
Ennis-Hill's 23-year-old team-mate Johnson-Thompson endured a disastrous World Championships, finishing in 28th place after failing to record a distance in the long jump.