The Power of Exercise

08/09/2011 12:26 BST | Updated 08/11/2011 10:12 GMT

Exercise is a truly powerful thing.

I came from a small town in Somerset. Everybody knew me. I was known as the boy who ran everywhere. I never walked. I ran absolutely everywhere. People assumed that I loved to run. To be honest, that have never crossed my mind, I just wanted to get where I was going as quickly as possible.

In my second year at secondary school, the PE session that everybody had been dreading, finally arrived. Cross country! After crossing the finish line, I had to wait fifteen minutes for the next kid to finish. The PE teacher, a well-known and celebrated cross-country runner, just stared at me wide eyed - he later called my Dad and informed him that his son was a cross-country runner. And so my cross-country career began. Nobody noticed that I didn't enjoy running, nobody noticed that I only ran to get where I was going as quickly as possible. I went on to compete at a high level in the UK and in Europe.

Luckily, at the age of thirteen, I had a horrible accident that almost destroyed my left knee. I couldn't walk for six months, and it took four years for my leg to look the same again. During my rehabilitation, I started swimming to strengthen the muscles around my knee. Unluckily, somebody called my dad and told him I was a swimmer. Three year on, I went on to become the Western counties champion.

At the age of nineteen, I'd had enough. While my friends were out on Saturday nights dating girls, I would be at a swimming gala captaining the Yeovil swim squad. It was a no-brainer, the swimming would have to go.

As the years went on, I invested my energy into my theatre company and my playwriting. I completed a film studies degree and later got a job as a runner in the post-production industry. I spent the next seven years sat in a chair and staring at TV screens - gaining a lot of weight and losing a lot of colour from my cheeks. Late nights, bad living, poor diet, and the accumulation of bad habits particular to the TV industry took their toll. I was depressed. So I left, my job, my house and my girlfriend and went home to Yeovil.

I remained depressed for a week or two, but this headspace seemed so unlike me. Something was wrong and I didn't know what. My instincts told me to get back into the pool and to regain my fitness. So I did.

At the end of the first week, I didn't feel much fitter, but I felt less depressed. At the end of the second week, I didn't feel that depressed at all. After six months, I could no longer relate to the depressed, overweight, low-energy person I had become during those seven years.

Exercise is a truly powerful thing.

For every positive physiological change that occurs in the body, there is a corresponding and equally positive change that occurs within the mind.

Having learnt this fact, through my own body, I didn't need to be told twice. I had been trying to decide which direction to my new career should follow and I now I knew - I would become a personal trainer. Now I would need to stay fit healthy and positive. What a great bi-product of my new career choice.

To find out more about Doug visit his website.

Read more posts from Doug Robertson at Body in Balance.