Get to know us.

Extension Fitness is owned and operated by Tim and Deb Karajas.

Tim Karajas

Tim’s a Perth boy, married to a Perth girl, and they have four beautiful daughters.

Most of Tim’s week is spent doing 1-1 or Semi-Private Personal Training plus Online Personal Training - including Running Coaching.

Tim earned a Bachelor of Science in Physiotherapy from Curtin University in 2000.

Then he spent 5 years in Musculoskeletal Private Practice in Perth.

This was a pretty bruising experience as Tim’s personal values did not align with the industry, which was often pseudoscientific and unethical.

Particularly galling was the high prevalence of over-servicing: getting patients back again and again to perform manual and electrophysical treatments of dubious value for the sake of boosting up appointment numbers.

After 5 years of this, Tim had had enough of the cognitive dissonance so he headed to the snow (working as a Liftie in Queenstown, NZ) before coming back to Perth and changing careers.

But the call of a career associated with exercise was too strong to ignore.

Tim had always been into training - deriving immense personal benefit from various endurance sports and strength training.

In particular, these pursuits had a profound healing effect on the anxiety disorder he had been carrying and helped him manage symptoms of Tourette’s Syndrome, which he’s had since a child.

Tim completed his Cert IV in fitness in 2021 then started Extension Fitness.

Tim believes in a “strength first” paradigm. Once we build up your strength, everyday movement and other forms of exercise become easier and more enjoyable, so you’re more likely to do them.

At all times he’s keen to ensure you’re moving with good technique and appropriate loads, so that your training is building you up and making life better, not breaking you down or leaving you sore and unmotivated.

With his background as a Physio, Tim enjoys working alongside other likeminded healthcare providers (Physio, Chiro, Osteo, GP) to help you overcome persistent pain. This area of his work is growing naturally as word spreads about the results people are achieving with Tim as part of their team.

He can also help you use exercise (in particular structured strength training) to help you address chronic health concerns like osteoarthritis, obesity and diabetes.

George Antonio

George grew up in Fremantle and started personal training from a love of going to the gym while at high school. He is a father of 2 young children and is well supported by his wife Candice.

George has been a personal trainer for 15 plus years. He holds a Certificate 4 in Fitness and also a qualification with the Titleist Performance Institute, which means he specialises in golf mobility and strength training. He is known for keeping middle age and older adults ‘flushing it on the course’ while staying pain free!

George is employed as a personal trainer by 2 local councils, the City of Bayswater and City of Swan. He also works as a support worker and in this role he takes young men with Autism to gyms for a workout and other physical activity.

George loves to train daily even if it’s just some push ups in the lounge room while the kids climb all over him. His belief is that we are designed to exercise daily in some capacity. Whether it be a 15 minute home routine, a 45min gym session or a sports based activity.

He is the perfect person to help you take positive steps towards a sustainable and empowering training habit which fits in with your life (and doesn’t take it over).

George works alongside Tim following the same training philosophy - emphasising proper technique, safety, and sensible progression. He’ll help you push yourself, but without injury or extreme soreness.

Deb Karajas

Tim’s wife and partner in crime, Deb, keeps the Extension Fitness accounts, managing billing, and helping out with various admin tasks as needed. She manages the home-front and, importantly, keeps Coach Tim well fed!

Unlike Tim, Deb was not historically motivated to exercise or play sport. You could say she’s more king charles cavalier than kelpie! However, in her late 20s she discovered some latent competitiveness and talent for running, and also discovered first-hand the many benefits of a regular exercise habit. Now a little older and a little de-conditioned after the last baby, Deb mostly focuses on strength training to lay a strong foundation for her ‘second half,’ and has also enjoyed playing a season of grass hockey.

Having benefited from Tim’s coaching and guidance herself, Deb loves supporting Tim’s work in helping others to overcome their fitness obstacles and reap the benefits of an active life.