It was eight weeks out from the Paralympics that Emily Petricola's preparations took an almighty hit.

The two-time Paralympian was diagnosed with Multiple Sclerosis (MS) in 2007 at the age of just 27.

Preparing to defend the para cycling C4 3,000m pursuit that she won in Tokyo, a flare-up in Petricola's condition threatened to take her out of the Paris Games.

Petricola worked with the Victorian Institute of Sport and other medical staff to give herself the best opportunity to race on the world's biggest stage.

"I just woke up one day and my back was in full spasm, which went into my left leg … it hasn't settled," she said.

"The medical support on the ground since we left Australia and prior to that, I wouldn't have been on the start line without those people."

Still dealing with the back and leg spasms, Petricola said it created doubt in her mind as she readied herself to race in Paris.

"It puts a lot of questions into your head around whether or not you can actually do it or whether or not I was going to be able to back up today," she said.

"One thing I know is the team around me. I've prepared me as well as possible and one thing I kept telling myself as I was warming up was that I've done the work, my body is ready to do this irrespective of how it feels."

Back on the bike and getting into condition to compete in Paris, Petricola suffered another setback when she crashed during training a fortnight from the Games.

"It's been really tough, (the crash) put a bit of a spanner in the works and set things off again," she said.

"I feel like every time I'm starting to take a step forward something from MS comes and presents its head.

"I believed that I would get here, it's just the level of performance that I would put out that was the bigger question for me."

The hard work paid off for Petricola, who won gold in the final over New Zealand's Anna Taylor, after setting a new world record during the heats.

The Australian now turns her attention from the track to the road, where she will compete for another medal in the time trial.

"My goal is to try and win. That's what I'm here to do, is to try and win two Paralympic gold medals," she said.

"It'll be really tough but I've got good people around me and we have done the work so hopefully we can have another great day."