Most working mothers are lucky to make a weekly yoga class or use the treadmill to stay in shape.
Mother-of-three Janet Smith instead lifts tractor tyres around the backyard of her Margaret River home or runs with ropes as thick as her arms.
The 35-year-old personal trainer knew nothing about obstacle course racing until nine months ago when a starring role in the ESPN television series Search4hurt earned her a wildcard entry to the extreme sport's national championships in South Australia.
Mrs Smith shocked herself and the rest of the field by finishing third and qualifying to represent Australia at the inaugural world championships being held in the US in October.
The unexpected success has meant Margaret River's own G.I. Jane putting herself through a personal boot camp to be ready for the gruelling 13km course that will pit her against steep hills, walls, creek beds and more mud than she can imagine. Mrs Smith said her unusual training regime had become normal for her three young daughters aged seven, six and three.
"I've got a gym set up at home here and I've got your big tractor tyres and ropes," she said.
"It's outside of the box, a bit more functional, a bit more fun."
Mrs Smith will warm up for the international challenge by competing in the inaugural South West Mudfest on July 19.
Registrations can be made at www.swmudfest.com.au .