Nairobi: Former world 800 metres champion Eunice Sum of Kenya has ruled out competing in indoor championships as she seeks to return to fitness ahead of the outdoor competition that will culminate in the Athletics World Championships in London in August.

Sum confirmed that she is back in training after a poor season last year and hopes to weather the storm and reclaim her title in London, reports Xinhua.

"The indoor championships are not my best and I do not want to put my body under a lot of pressure. It is good to focus on one thing and do it well. I will run the outdoor competitions alone," she said on Friday.

Sum, 28, had a torrid time last season which started with the doping scandal that involved her manager Federico Rosa.

Though she is not suspected of any role in the scandal, she found it hard to train as her mentor and manager was tormented by the Kenyan authorities before the case was dropped.

Now she has resumed training after her poor show in the Rio Olympics and hopes she will have gathered enough strength to go for gold in London in August.

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"It is not easy when the person you look up to, the one who has been helping you is in trouble even if it has nothing to do with you," said Sum.

"It weighs you down and focus is shifted. I have been training all along since last year after the Rio Olympics and I am really focused this season."

There will be no time to waste for Sum though. She is already planning for the Diamond League season, which starts in May in Doha.