Wheelchair athlete Richard Nicholson during training at the Australian Institute of Sport in Canberra in preparation for the 2012 London Paralympic Games.

Wheelchair athlete Richard Nicholson during training at the Australian Institute of Sport in Canberra in preparation for the 2012 London Paralympic Games. Photo: Alex Ellinghausen

Powerlifting had become so tainted by drug cheats, Canberra's Richard Nicholson turned his back on the sport never to return - despite winning a silver medal at the 2000 Sydney Paralympic Games.

Nicholson will compete at his fifth Paralympics at the London Games in August, but instead of powerlifting he'll be racing in the 400 metres sprint, the 4x400m relay, as well as the 100m sprint.

The 41-year-old wheelchair racer also won silver as part of the men's 4x100m relay team at Athens in 2004, a feat he probably wouldn't have achieved if it wasn't for the tainted nature of powerlifting 12 years ago.

Eleven competitors returned positive drugs tests at the Sydney Paralympics, of which 10 were powerlifters. The International Paralympic Committee was so concerned with the legitimacy of the sport it will test every powerlifter in August in the lead-up to the London Games.

For Nicholson, whose legs were paralysed after an illness when he was four, his time had come to get out of the sport.

''I got a silver medal in Sydney and I thought, 'that's the best I could do playing by the rules','' he said. ''I didn't think I could do a lot better against guys who were cheating.''

There was never the temptation of ''if you can't beat them, join them''.

''It goes against every fibre in my being to do that. You play sport, you play hard but you play fair, so it wasn't something I was tempted to do and at that time it wasn't an option for me so I just chose to do something else,'' he said.

''I think [the sport has] improved. I don't want to dwell on that sort of thing. Unfortunately it's just part of sport. It's not necessarily the ones earning a lot of money, either. There's no money in Paralympic sport but people are still keen to do it.''

But Nicholson doesn't want to be seen as taking pot-shots at powerlifting. His change was also about having more events to compete in throughout the year. He competed in Switzerland last month and if he can repeat those efforts, he'll make the final of the 400m in London.

If he gets there, beating his personal best of 48.2 seconds is the goal and a possible podium finish.

''My goal is to make sure I do the best I can do, just do a PB and if that's good enough on the day that will be in the final on the podium with any luck,'' Nicholson said.

''I guess we had a really good competition in Switzerland last month and I was happy with my result there and on the current rankings I think that puts me in the top eight. That's in the final, if I can do that and a little better I'll be quite pleased.''

Nicholson also competes in marathons, winning silver and bronze in the 2010 and 2011 Sydney marathon respectively.