For Canadian astronaut David Saint-Jacques, it's all about preparation as he continues his training four months before he blasts off into space.

Saint-Jacques, 48, is currently in Moscow along with U.S. astronaut Anne McClain and Russian Oleg Kononenko, who will join him on board a Soyuz aircraft when it launches for the International Space Station from Kazakhstan on Dec. 20.

"The goal is to get to the day of the launch with a clear mind and the confidence you have full possession of your faculties," he said in an in-person interview with The Canadian Press on Thursday.

"I like the mountain analogy. Right now, I'm climbing Everest. If you ask a climber who is two-thirds up Everest if he is excited about soon getting to the top... no. He is concentrated. He doesn't want to trip up, doesn't want to get caught in his rope."

The Quebec native, who will become the ninth Canadian to travel to space, will serve as a co-pilot for the Soyuz capsule and, because of his medical training, will be the crew's doctor on board the station during the six-month stay.

Saint-Jacques is expecting stiff challenges during gruelling training tests Friday.

"At the beginning, you don't know what to do...but finally you get better and at the end you survive almost everything they throw at you, and you're ready," he said.

An astronaut since 2009, Saint-Jacques was named to the mission in 2016.

Trained as both an engineer and a doctor, Saint-Jacques will be the first Canadian aboard the space station since Chris Hadfield spent five months on it in 2012 and 2013.

McClain, who also will be flying into space for the first time, said she is happy to be doing so with her Canadian teammate.

"I knew David before I was assigned to this flight and I was very happy when I got the assignment with him," she told The Canadian Press in a separate interview. "And I've gotten to know him even better over the past few years. And I think the most important aspect of a crew is trust -- and I have come to trust David both professionally and personally.

"All of our lives are in each other's hands in the Soyuz and I trust him to do the right thing. And personally, I can rely on him for anything that comes up in my own life."

Doug Wheelock, the NASA director of operations at the Moscow space facility, also had kind words for Saint-Jacques.

"He's a smile with legs, so David is just a joy to have on our team here," he said.

"He's got an effervescent personality that tends to draw everyone in...David has been just a real jewel for us."

Wheelock said being in space is "like a ballet on fingertips."

"David is very well-tuned, he's got the hands of a surgeon, so he's got a very light, very commanding touch on the control systems and he'll be a great space flyer," he added.

Saint-Jacques will celebrate his 49th birthday on the space station Jan. 6.