In among a sea of activewear and exercise gear, the second-year medical student's running attire certainly stands out.

However, running in medical scrubs for 42 kilometres presents unique problems.

"It accentuates lots of things and there's some extra chafing as well and it's pretty sweaty underneath there," Mr Siddall said. "The wind turns it into a parachute and it makes it a lot more challenging."

While Mr Siddall's running get-up may seem like a novelty, there's a more serious side to the scrubs.

The 24-year-old will be running in the medical uniform for The Canberra Times Marathon Festival in April in an effort to raise awareness of mental health among doctors and medical staff.

The medical student will be running as part of a team of medical students, all wearing medical scrubs, raising money for Beyond Blue.

Mr Siddall said for many doctors and medical students, mental health issues remained hidden from public view.

"There's a perceived stigma that if you have mental-health concerns as a doctor, people see you as a worse doctor, and that's a dangerous attitude to have," he said.

"Many work long hours and what comes with that is exhaustion which can lead to greater mental health concerns, and combined with the pressure of a high-pressure job, many people are silently struggling."

A recent Beyond Blue survey into the mental health of doctors and medical students found the cohort reported substantially higher rates of psychological distress and suicidal thoughts compared to other professions.

The survey of more than 42,000 doctors and 6000 medical students also found stigmatising attitudes regarding mental health also persisted.

"Doctors are often seen as quite stoic people and quite hard working, and I'd love for people to realise they're also human and struggling with their own mental health and feel like they can't speak up," Mr Siddall said.

The medical student said running and exercise was a key factor in maintaining his mental health. He said he began regular running in an effort to boost his own mental health and hasn't looked back since.

The upcoming run will be Mr Siddall's second marathon, having completed his first in 2017 in Sydney.

His preparations include running at least 40 kilometres a week, and has already run several times in the scrubs to prepare for the main event.

"If you had told me three-years-ago that I would be running a marathon, I would've laughed at you," he said. "It wasn't something I would do for fun."