I call myself an accidental athlete I first realised my capacity for endurance while I was [working for an NGO] in Nepal. I would cycle every day with friends and Nepali sherpas, and I outperformed all of them. So I started doing marathons and triathlons when I returned to the UK, and didn't stop. I'd never in a million years thought I could win the Ironman World Championships once, let alone four years running.
Sometimes your worst races are your biggest triumphs They enable you to develop and grow and learn. What I've learnt most is to keep a sense of perspective.
Sacrifice is not a word I like It has too many negative connotations. But it's true you do have to forgo certain things while you're training. I can find the lifestyle very mono-dimensional and incredibly monkish. I'm an all-or-nothing person, and I give everything I have to my training. It can get a little all-consuming.
I like to splurge on burgers, pizzas and kebabs after a race after months of watching my diet. But only temporarily, as I believe in everything in moderation; ultimately I'm much happier with brown rice, brown pasta, fresh fruit and vegetables.
I suffered from bulimia when I was 16, 17, 18 and then from anorexia during my MA. I look at my body in a more holistic sense these days. Rather than looking in the mirror and seeing a particular image, I see a body that has enabled me to achieve great things. I hope that by sharing these issues I might impart a positive message to others.
Mediocrity in life doesn't interest me Although I never take a win for granted, it's always at the forefront of my mind. To be happy in life, I think, you have to adjust that mindset. Trouble is, it's difficult.
I draw heavily on the Rudyard Kipling poem 'If' I write it on all my racing water bottles and I carry a dog-eared copy around with me everywhere. It's so motivating. I repeat its first line constantly: "If you can keep your head when all about you are losing theirs..."
Chrissie Wellington, 35, is a British triathlete and four-time World Ironman Champion. Her autobiography, 'A Life Without Limits: A World Champion's Journey', is published on Thursday by Constable, priced £18.99