People are doing push ups in pyjamas, on median strips, with their kids, with their pets and disguised as super heroes.

It's fun, yes, but the message at the centre of this campaign  could hardly be more serious. 

The profusion of push ups is helping to bring a secret, once hidden epidemic of post traumatic stress in our military to the forefront. 

Over in Canberra, from where Australia's defence operations are orchestrated, Fairfax journalists at the Canberra Times are also shining a light on the issue.

In a series of articles titled “The Silent War”, former commander Australian forces in the Middle East, Major General John Cantwell describes the looming crisis among returning soldiers as “a wave of sadness".

He warns a flood of soldiers from the battlefields of Afghanistan and Iraq will  present with serious psychological damage in the coming years.

And he knows all about this – General Cantwell himself suffers from PSTD related to his war service. 

He has gone on to write a book, Exit Wounds, of his own experiences, tracing his path from distinguished military career to a psychiatric ward.

He says we have exposed thousands of Australians to brutal experiences and we need to be ready for the fall out. 

Of the more than 45,000 Australians who have served in conflicts since 1999, it's estimated that nearly one in five will suffer a mental disorder.

But expert evidence suggests the actual numbers seeking treatment may be closer to 25-30 per cent, in line with the |US.

And it was in the US that the viral sensation of 22 push ups began – when statistics there showed 22 servicemen and women per day  were dying by suicide.

More recent figures report this has dropped to 20 per day, with the organisation behind the campaign, Honor Courage Commitment, saying they won't stop until this number is zero. 

In terms of dealing with war trauma, we have come a long way since the days when "shell shock” was spoken of in hushed tones.

Whether you can manage 22 push ups or not, let's keep this conversation going.