How an Olympic swimmer tried too hard, then found a balance to life

I grew up in Melbourne, in a house 100 metres from the sea, and spent much of my childhood either at the beach or in my neighbour's swimming pool. I didn't take formal swimming lessons but my older brother did, so I just copied what he was doing. I was into all the sports - I won a football (Australian Rules) scholarship to high school and played baseball at the national level, but when I was 13, I decided to concentrate on swimming. I was getting frustrated with having to rely on other people's performances in team sports. With swimming, I knew it was down to me, and that I'd reap the rewards for the hard work I put into training. That really appealed.

When I was 16, I trialled for the 2004 Olympic team but missed out by 0.1 seconds. Two years later, I made the world championship team and shortly after, graduated from school and moved to the Gold Coast, to become a professional swimmer. It was a great place to swim, with beautiful facilities and gorgeous weather. During a typical week, I'd spend 20 hours in the pool and five hours in the gym, plus yoga, pilates and spinning. I spent a lot of my downtime in the sea, swimming and surfing. When you spend that much time in the water, you get a feeling of becoming one with it, which helps you become stronger and more capable, even when you're not training. I never found the training boring. Others saw it as a sacrifice, but I loved pushing myself to my limits. I knew what I wanted to achieve and the discipline required came naturally.

I made my first national team swimming backstroke because there was a weakness in the Australian swim team, so I grasped the opportunity. But my best stroke is butterfly, so, after a couple of years, I switched. When you swim butterfly … well, there's no better feeling. You take a breath as you go over the water and if you time it right, and hit the sweet spot, you feel as if you're floating. I made the Olympic squad for the Beijing Olympics in 2008. I hit my peak at just the right time. My coach and I had developed a "not trying" technique, which made me fluid and relaxed when racing - I wasn't going to be rattled by anything. I won three medals (4x100-metre freestyle relay - bronze; 100-metre butterfly - bronze; and 4x100-metre medley relay - silver) and it was an incredible experience. The Olympic village was great, the volunteer staff were fantastic. All the Australian swimmers thought the Water Cube was the best-looking pool we'd ever seen. The swimming all took place in the first week so, during the second week, we explored the city and visited little villages with rivers and lanterns and nice restaurants. I also spent a lot of time at a nightclub called China Doll - that was fun.

The last two years of my career were tough - I didn't swim a good race and my results went backwards. I started overthinking it, stressing about it - it's like trying to outsmart something that only really works if it comes instinctively. With swimming, you've got to have a feel for the water, and make sure you catch and move it at the optimal time. If you pull too hard and rip at the water, you slow down. It's all about efficiency and using the right amount of force. If you think too much, your body tenses. I swam better when I wasn't consciously trying, and just focused on the rhythm and feel of the strokes. My response was to train harder. When I was younger, the harder I worked the better I swam. So I started secretly sneaking in extra gym classes and spinning sessions but instead of making me fitter, it wore me down, because I wasn't giving my body the opportunity to rest and recover. As a result, my adrenal system was shot, my testosterone levels were lower than a female's and I couldn't perform when I needed to. My body was sending me a message.

I realised I had to work out how to live a more balanced life. I needed to switch off from swimming when away from training, and find other things to occupy me. I started studying yoga and meditation, and exploring opportunities in the business world. I worked at and became part owner of Engine Swim, a company that makes swimwear and accessories for performance swimming and surf lifesaving. I have since started up a learn-to-swim centre, New Wave Swim School, in Melbourne, with my dad and brother. I retired from professional swimming in 2012 but I wanted to stay as fit and healthy as possible. A mate introduced me to CrossFit and I was instantly hooked. As a swimmer, all your training is geared to achieving the fastest time and once you get really good, it becomes increasingly hard to improve your scores. CrossFit's the polar opposite in that it's about being competent at everything - running, rowing, Olympic weightlifting, bodyweight movement, gymnastics. The idea is that you don't become the best in the world at any particular discipline, but you see gradual improvements in all of them. I competed at the highest level at the world CrossFit Games in California, last year, which was awesome.

And I've got a new job teaching swimming and CrossFit for Chosen, a company that runs wellness and adventure holidays in Bali, New Zealand, Guatemala and Iceland. It's designed to help stressed-out people calm down, get healthy and restore balance in their lives.