Heather Fell, Olympic modern pentathlete silver medalist, writes about her life 'on and off' the track.

PREPARATION for my weekend event was far from the perfect model of a gentle taper in training, healthy eating and a good sleep pattern – apparently you can get away with that in your twenties.

My training consisted of running further than intended as I just enjoyed the Californian sun on my back a little too much, that teamed with it being a perfect method to see so many of the sights. Once home I attempted to rest my legs, so thought what better time to head out on my bike - surely if you are sitting down it doesn't count? It was however, my first time ever on a road bike so containing my excitement and not sprinting up the hills was a challenge. I was concerned by the group's reaction when they discovered that not only was I running a half marathon the next day I also didn't have any padded shorts or cycle gear — just extra layers of my running kit.

As for nutrition there were copious amounts cookies and ice cream oh and 'cookie ice cream sandwiches' – yes you heard me right. It has to be the most unhealthy yet best sandwich ever invented – affected the plan of the lighter I am the faster I would run went out of the window.

The final factor was more out of my control due to the eight-hour time difference but my ability to sleep anywhere and anytime reduced this problem significantly. All of this teamed with the fact I entered my next decade on the morning of the race meant I was not holding out high hopes; so you can understand how I reasoned to myself during the run when I thought I was down on my target pace. Having only ran one half marathon before I had little to compare to and it seems that my calculations along the route were far out as I finished with a surprising 12 minute personal best – a perfect birthday present!