NAIROBI, Nov. 12 (Xinhua) -- Two-time Olympic 800m champion David Rudisha will race sparingly ahead of the 2019 World Championships to avoid a recurrence of the injury that kept him out of competition for a year.

The 29-year-old Kenyan is working around the clock to preserve his fitness and put his name up for contention for a third Olympic gold in Tokyo in 2020.

Speaking in Nairobi, Rudisha says a quad muscle strain that forced him to skip the 2017 World Championships has fully healed.

He also says he has shaken off an irritation around the sitting bone, a condition that causes hamstring problems, and will be ready to recapture his world title in Doha, Qatar in October.

"Many times I worried if I would ever return to competition. This is not the first time injury has plagued my career. But it sent me to the brink and I doubted whether I could make a comeback.

"But I found inspiration and worked hard to overcome it and now I have slowly resumed training. I have been running in Nairobi and Eldoret and now I hope to do well in the 2019 season," Rudisha said on Monday in Eldoret.

In 2013, Rudisha suffered a knee injury while training in New York that failed to heal in time for him to defend his world title at the Moscow World Championships.

He returned to fitness and was able to retain it in Beijing in 2015 and went on to win gold at the Rio Olympics.

However, injury slowed him down in 2017 and he had no choice but to stay out of competition in 2018. But the 29-year-old is now back to his best form and will be dreaming of regaining his fitness that saw him run over 27 races without defeat from 2011 to 2013.

"I want to see how I will fare in competition. But I must say that I will not run in as many races as before. Injuries may have taken a toll on my body and my speed may not be as fast. I will be very careful as to where I compete in order to reserve my energy for the World Championships," he said.

Rudisha will also have one eye on competing at his third Olympics.

Having missed the Beijing 2008 Games with a tendon injury, Rudisha won in London 2012 in a world record time of 1:40.91, and retained his crown in Rio four years later.

He wants to go an extra mile and bag his Olympic medal to cement his status as a true legend.

"My focus is on the World Championships. But I also want to run at the Olympics," he added.