Navy has supported a 57km charity run from Sydney's North Head to South Head that raised vital funds for Australian veterans.

A small group of Navy people were among those who completed the head-to-head Run, which travelled through Navy establishments HMA Ships Penguin, Waterhen, Kuttabul and Watson.

Organised by military charity Bravery Trust, the Bravery Trek goes for 31 days as an official Veterans' Health Week event and can be completed on foot, on a bike or in the water.

The head-to-head run in Sydney was completed in just one day as a launch activity to kick-start efforts to raise money for veterans.

Aviation warfare officer Sub-Lieutenant Tiffany McCormack finished the run and said it was great to be alongside a group of like-minded individuals all working towards the same cause.

"I always felt as though I appreciated the necessity of supporting veterans but this experience really made me realise just how much this support can mean to someone who is struggling," Sub-Lieutenant McCormack said.

"Awareness is such a key factor and Bravery Trek allowed us to speak to so many people along our 57km adventure - people who potentially hadn't considered the effect service life can have mentally and physically."

Navy veteran Murray Bruce, a former submariner who joined at the age of 15 before returning to high school and later re-joining as a weapons electrical engineering officer, ran the course to launch the trek on October 10, accompanied by the Navy personnel and other runners.

Mr Bruce served in submarines and developed a passion for veteran advocacy that he has channelled into Bravery Trust and the Bravery Trek event.

"It's OK not to be OK when you leave the military. We often carry home a hidden kit bag full of health and mental health struggles we've incurred during our service," he said.

"Sadly, veterans often distance themselves from those around them and feel isolated and disconnected.

"Bravery Trek raises vital funds to close that gap, to increase awareness of the available support, to say 'it's OK to not be OK', and to put roofs over families and meals on tables when they are needed.

"In addition, through counselling they're helping vets and their families dig themselves out of unenviable holes that their circumstances have forced them into."

Go to braverytrek.com.au