A former Australia's Strongest Man winner and World's Strongest Man entrant, Mr Edwards pulled a 10-tonne fire engine up the driveway of Government House on Tuesday morning.

It was all in the bid to break the Guinness World Record for the fastest time to pull a 10-tonne fire engine 50 metres - the current record of which is one minute and seven seconds.

But more than that, Mr Edwards wanted to mark PTSD Awareness Day and raise awareness for the important work of charities FearLess PTSD Australia New Zealand and Integra Service Dogs Australia.

While Mr Edwards did not complete the 50 metres, he did manage to pull the ACT Emergency Services vehicle to about the halfway mark - receiving a cheer from the crowd and an impromptu rendition of You Are My Sunshine by Linda Hurley, who was watching on with her husband Governor-General David Hurley.

"I'm disappointed that I didn't do it because I honestly thought I could do it," he said.

"But once it stops, and you're halfway through, it's really hard to keep going. And technically, with the Guinness rules, once the actual implement stops, you've got to stop the attempt. But I thought I could at least get through to the finish.

"But it won't stop me, I'll have another go. The cause is greater than the individual. The more we can get people understanding about post-traumatic stress and the impact that it has, and the fact that it's not a life-limiting situation."

MUST READS:

This is not the first time Mr Edwards has tried his hand at pulling heavy loads, having already pulled aircraft - including a C-17 and a C-130 - a steam locomotive and a ship.

When it came to training for such an event, however, Mr Edwards said it wasn't just about strength alone.

"Strength is still important but it's about being able to sustain a load for a couple of minutes. So it's almost on that threshold level of the human capability where you're not doing strength, you're not doing aerobic, you're doing both," he said.

"For me, I couldn't get access to pumpers all the time, but it's just a lot of work with the legs and I did a lot of cycling this time, which I haven't done for a long time. That's the closest thing you can do."

Mr Edwards is an ambassador for both FearLess - which supports people living with post-traumatic stress disorder - and Integra Service Dogs Australia - which delivers assistance dogs to veterans and first responders with PTSD.

But for Australia's former strongest man, the cause is personal, as he lives with PTSD.

"I call myself a statistic. I'm one of the statistics on both sides in terms of, attempting to take my own life, but also PTSD," Mr Edwards said.

"It's cathartic when you start to get clarity about what can you do to help others not end up where I ended up. And then part of that is one, talking about it, but also two, about getting people to understand that, sure, we talk about the stigma of it all and stigma is still alive, but I prefer to talk about normalising it."

Support is available for those who may be distressed. Phone Lifeline 13 11 14; Mensline 1300 789 978; Kids Helpline 1800 551 800; beyondblue 1300 224 636; 1800-RESPECT 1800 737 732.

We've made it a whole lot easier for you to have your say. Our new comment platform requires only one log-in to access articles and to join the discussion on The Canberra Times website. Find out how to register so you can enjoy civil, friendly and engaging discussions. See our moderation policy here.

Our journalists work hard to provide local, up-to-date news to the community. This is how you can continue to access our trusted content: