MOTHER of three Trish Ham is the instructor US Navy SEAL recruits fear.
The personal trainer, who grew up in Ipswich, has undergone an incredible career change, leaving her nursing career to follow her passion.
Living next door to St Andrew's Hospital, nursing was an obvious career choice.
But after doing her training at Ipswich Hospital and working as a nurse at several hospitals, she discovered boxing.
"I enjoyed it, lost a lot of weight, went and saw a personal trainer myself, loved it, so I did my own training course and became a trainer after that and realised how awesome it was," she said.
She took on personal training work part time while working as a nurse since 2003.
When the family moved to Kentucky in the US for her husband's work six years ago, she saw the opportunity to move into personal training.
She volunteered to train Navy SEAL candidates and hasn't looked back.
The candidates go through two and a half hours training a day, six days a week, to prepare for Navy Special Warfare recruitment.
"It is extreme training," she said.
"We do strength training, we do a lot of stuff with sandbags, log training where they hold logs over their heads.
"They do a huge amount of running, push-ups, pull-ups and sit-ups, which they have to be awesome at. They swim a lot too, they have to be good underwater.
"Someone asked me to come and give these guys a kick in the butt and I did. So I thought I might as well keep training them so I trained them in the gym."
The work then lead to the US Navy's recruiters sending her all their special warfare candidates.
"They have to do much better than boot camp. They are the top guys. They have to do 100 push-ups, 100 sit-ups, 20 pull-ups, they have to run a 5-minute-30-second mile consistently. They have to swim fast," she said.
"Usually when they get to me, most guys can pump out 50 push-ups, but they can't, under pressure, pump out 100. So my first job is to get them really good, passing basic training, get their contract, then we get them ready for BUD/S (Basic Underwater Demolition Seals Training). When they leave me, they go to boot camp, they go to special warfare prep, then they go to BUD/S.
BUD/S is where they experience brutal training including the famed "Hell Week".
Mrs Ham has 12 candidates at the moment, 18-26 years of age, which she trains for 6-12 months before they can get a contract with special warfare.
At 163cm in height, she manages to shame them into getting through the training.
"They are all slightly scared of me. They just know that I have a bit of power over them," she said.
"I'm not like a drill sergeant. I tell them the truth. I am more an encourager than anything.
"No-one has ever said anything about me being an Australian or about being trained by a girl.
"I do a lot of the training myself, but I just say "I can do it, watch me do it", and I've just done it for 30 seconds. They hold on to a 70 pound (32kg) sandbag for two hours and run a couple of miles, do tonnes of squats and lunges.
"I see my role more as building them up and getting them ready. My mental training is making them do hard things for a very long time and not giving up, teaching them not to be quitters."