Swimming Icon Michael Phelps Aiming High for Rio Olympics

American swimming legend Michael Phelps aims for more glories at next year's Rio Olympics after coming through the toughest period of his life.

Phelps, who has won 18 Olympic titles, suffered a setback in September 2014 when he was arrested for drunk-driving after a night out at a local casino in Maryland -- the second time he had been found to be driving under the influence of drugs or alcohol, reports Xinhua.

He pleaded guilty to drunk-driving and was given one-year suspended sentence and 18 months' probation, but was spared jail.

The 30-year-old Phelps says after the arrest he spent four days in his Maryland home before realising he had to get his life back on track.

"I was in a real dark place. Not wanting to be alive anymore," he told American magazine Sports Illustrated.

"I look back now, I lived in a bubble for a long time," he said.

His coach Bob Bowman believes Phelps is healthier than ever and is on target for a further six gold medals at the 2016 Games in Rio.

He has not drunk alcohol since his arrest, and has vowed not to drink until after the Rio Olympics next August.

"You're going to see a different me than you saw in any of the other Olympics," he said.