SIX-time world short-course champion Mark Foster admits deciding to attempt to qualify for his fifth Olympics was a slow process.

The Billericay-born 37-year-old cruised through to the finals of the 50m freestyle at the British Championships, which double as the Olympic trials, in Sheffield last night.

Foster clocked 22.29 seconds to cover the 50m course and finish in first place, exactly a tenth of a second faster than second place man Simon Burnett.

It marks a turnaround for the Bath University swimmer, who had announced his intention to quit international swimming after the 2006 Commonwealth Games.

Foster never officially retired and returned to competition last summer to claim both the 50metres butterfly and 50m freestyle titles at the ASA National Championships.

This qualified Foster for the World Short-Course Championships in Manchester taking place straight after the trials.

Now Foster can complete the turnaround when he attempts to overcome the bitter disappointment of his failure to qualify for Athens as long as he can achieve the qualifying standard of 22.35seconds for the 50m free, his solitary event.

"First and foremost all I did was go to the gym to keep in shape and go to the pool because I enjoy the feel of it and it's very spiritual - water - and whether I swum once a week or once every two weeks I enjoyed it.

"I did a couple of invitational meets in Europe and had some great results and thought - well hang on, I'm not doing an awful lot and I'm swimming this quick, why don't I do a little bit more training again and let's see what we can do.

"That was after Sheffield. So I thought if I'm going to be fit and I'm going to be ready why don't we see what we can do at the trials? So that's how it all came about."

Foster also admitted it would not erase the disappointment he felt over Athens.

"I was obviously devastated not going last time when I think the year before I was world short-course medallist and was in the form of my life," he said.

"Because I got an injury beforehand that was really soul-destroying so this won't make up for that. But I am just seeing what happens. The biggest thing for me now is that I'm doing it because I want to do it."

Foster swims in the 50m free final this morning at Sheffield's Ponds Forge.