In winning four in London, Cole sat alongside Australia's swimming stalwarts Matthew Cowdrey and Jacqueline Freney in doing the heavy lifting for the nation's medal count.

Fast forward to Rio and Cowdrey and Freney are missing from the Australian swimming team. Cole, 24, is suddenly one of the leaders among the green-and-gold contingent.

That pressure can have an impact. Cole admitted as much after winning her first individual gold medal at these Games on Friday (Saturday morning AEST), topping the podium in her women's 100m backstroke category.

"It's day nine of competition, that can be hard for any athlete," she said.

"I was watching the Olympics and watching the swimmers come out of the pool and saying how much of a rollercoaster the emotions were, and I completely understand what they were talking about now.

"I knew that I was [the] world record-holder going into that race. I was still questioning if I was worthy to be there heading in, and I knew that I was, but it's amazing that even after the amount of psychological sports training that I've had, those thoughts still come in and take you down."

Cole (1:09.18) finished less than half a second ahead of Spanish teenager Nuria Marques Soto (1:09.57).

"I don't know if people that age [17] feel any pain when they swim. I have no idea. But they just keep coming at you," Cole said.

"As you get older it can be hard to have the same enthusiasm going into a race. Once you start getting beaten a couple of times, that thought of you being invincible disappears, and you do start questioning yourself."

Cole takes home six medals from Rio, winning her third silver on Friday after joining with Lakeisha Patterson, Maddison Elliott and Madeleine Scott in her women's 4x100m medley relay.

Her surprise second came on day two in the women's 400m freestyle (S9). Cole opted to also do that race, a distance she admits that tests her, because otherwise her program would have started on day five.

The former Victorian, who now trains at Castle Hill in NSW, said the past four years had been challenging after surgery on both her shoulders in 2013 and a change of coach.

"I had to change my training program quite drastically," Cole said. "I chose a coach who had never had any experience with a first class athlete.

"We're actually the same age. He was actually my boss when I started working with him. It was a bit hard to go from one of my closest friends to all of a sudden my coach telling me what to do.

"But it's a relationship that's worked really well. I find for the first time in my life I'm working with my coach. We don't have that hierarchy there.

"I guess it's really made me find that passion for sport again, because I personally have invested so much these last few years, as well as him.

"I feel like I had the responsibility on myself to bring home a gold medal for both of us today."