Kate Percy - Go Faster Food: Over 100 energy-boosting recipes for runners, cyclists, swimmers and rowers

'Man ist was man isst' 'You are what you eat'. I would never have believed that these words would ring so true when I used them for my German thesis in those heady days as a student in southern Germany in the 80s. The nearest I came to sport then was a few leisurely descents of the local ski slope to the caf for a glass of wine and a cheese fondue. How things have changed. I fell in love with a sports fanatic, married him and, despite several years of dragging my feet, ended up an enthusiastic and capable marathon runner.

This happened by accident really. Faced with the dreariness of watching my husband train for and run yet another marathon, I decided that enough was enough; I had to see for myself what all the fuss was about. After a few weeks of running two to three times a week, I started to really enjoy myself. I felt less stressed, more positive and full of energy. I decided to go the whole hog and to train for the New York Marathon.

Since then I haven't looked back. I have run the New York, Amsterdam, Berlin and London Marathons and now have a good enough qualifying time for entry into prestigious marathons like Boston. I also love running half marathons and cross-country races and I have even tried my hand at fell running. If I were a better swimmer I would be very tempted to have a go at triathlon, but I'll have to work on that one ...

I find that the main problem with doing all this exercise is fuelling the body adequately. Athletes, whether amateur or elite, really do have unique nutritional demands. When we are training, we can be burning up to several thousand calories every day. No wonder we get hungry. We can, and we should, eat more than the average person. Eating and drinking properly needs to become an essential part of our everyday routine and sticking to a good diet, especially in those hard-training weeks leading up to an event, can not only have a dramatic effect on stamina and performance, but it can also make our training easier and even help the body repair and improve itself.

I became interested in the best foods to eat for endurance a few years back, when my husband was training for New York in 2000. His training started well, but he gradually began to sound like a stuck record, complaining every day that he was tired and hungry and yawning constantly. I decided to study nutrition, I changed our diet and, like magic, he began to feel more energised and started to really enjoy his running.

I have become increasingly fascinated by how some foods help endurance and recovery better than others and why, when you lapse for just one day, you start to feel lethargic, your energy levels drop dramatically and you are unable to fulfil your potential. What is also so interesting is that it is not just what you eat and drink that is important, it is also how much you eat and