Australian Olympian Sam Willoughby says his recovery from the BMX cycling crash that paralysed him is continuing positively.

While the London Olympic silver medallist accepts his racing days are over, Willoughby is now focused on walking fiancee Alise Post down the aisle when they marry on December 31.

Willoughby has progressed from cycling on a stationary bike to crawling on his hands and knees.

Willoughby endured a horrific fall while training on a BMX track in the US last September.

The impact initially left him with no movement from the chest down, after he sustained fractures to vertebrae that severely compressed his spinal cord.

Since then, the 25-year-old from Adelaide said he constantly improved at rehabilitation exercises.

“I can ride the bike pretty easily now and am doing quite a bit of crawling,” Willoughby told News Corp from the United States, where he is receiving treatment.

“I’ve progressed to using ankle weights when I do that now to try to strengthen up whatever function I’ve got in my hips.”

Anyone need a starter for Tokyo #notquitedoneyet #getupyoudog #biggears

A post shared by Sam Willoughby (@swilloughby91_) on Apr 17, 2017 at 1:31pm PDT

He said he could last three minutes standing on a vibration plate, up from 30 seconds when he started.

Willoughby in April posted an Instagram video of him on an exercise bike, with the caption, “anyone need a starter for Tokyo #notquitedoneyet”.

But the two-time world champion said he was comfortable with no longer being able to race.

“Obviously I didn’t want it to end this way but it puts things into perspective,” he said.