I had finished the first draft of my book before entering for the Tony Lothian Prize. I knew I had uncovered a really good story, about my eccentric, difficult father, the physiologist on the 1953 Everest Expedition. I couldn’t bear him, yet felt bound to write about him. Without his work, the Everest ascent in 1953 would not have been possible. Nor would the world-wide revolution in high altitude climbing that followed immediately afterwards. Yet he remained unknown to the general public and would soon be completely forgotten.

Once I began researching his life I found the subject – and the surrounding history – so fascinating and multifaceted that it could hardly be contained within the draft I eventually produced: a tome some 230,000 words covering every detail of my father’s life from cradle to grave.

There seemed no doubt that this very long book about an unknown scientist by an unknown author was destined only for vanity publishing. But then, someone suggested I enter for the Tony Lothian Prize (TLP). To my amazement, I won the Prize in 2009.

Four years later the book, published by Rider (Random House), became runner up for this year’s HW Fisher Best First Biography Prize, behind Charles Moore’s biography of Mrs Thatcher. My book has also won the Boardman Tasker Prize and the Banff John Whyte Prize for non-fiction mountaineering literature, and was longlisted for the Samuel Johnson Prize. This run of extraordinary good luck owes an amazing amount to the TLP, which had a four-fold impact on me.

The Prize began exercising it influence when I had to prepare the competition entry. I already had a gripping chapter describing the shattering moment when, at the age of 46, I first found out about my father’s contribution to Everest. But I also had to write a four-page synopsis of the whole book. Faced with the need to impress the judges, I reached for a graphic scene describing a young doctor arriving at my father’s laboratory to ask his advice, and finding a semi naked, chalk-white, phantom figure with wild red hair lying in a state of collapse in a Victorian bath full of cold water and floating ice cubes. At this point it suddenly dawned on me that the book needed to grab readers’ attention in much the same way. I had to make them want to turn the pages. I had been so busy writing down facts that this overwhelmingly obvious point hadn’t occurred to me before.

But without the great boost to my confidence conferred by the winning of the Prize, I don’t think I would have found the energy and persistence to rewrite the whole book completely, and then cut it drastically twice more.

Another effect of the Prize was to open doors for me in all kinds of ways –it gave me credibility when I interviewed subjects, it helped me to find an agent, and it helped me to find an editor and a publisher.

There was one further profound effect. At the prize-giving dinner, four seasoned biographers including one of the judges – John Guy – came to give me advice. All of them said the same thing: “Don’t imagine this book will be a success if you just write about your father’s life and scientific career. You must put yourself and your journey of discovery into it.”

I found this rather annoying. I didn’t want to write about myself, and except in the introduction, I hadn’t done so. It was true that the introduction seemed to promise the book would have a personal dimension, but until then I thought I could get away without delivering it.

I might have ignored one or two people’s advice, but I really couldn’t ignore four. So when I rewrote the whole book – this time with help from an editor – I wove my personal story into it. That part was surprisingly painful. One day while discussing my father with my editor, he became exceedingly uncomfortable. “You’re not going to cry are you?” he asked, looking horrified.

My book is the first TLP winner to have been shortlisted for the HW Fisher Best First Biography Prize. Although it didn’t win, I am over the moon about the result.

Harriet Tuckey is the author of Everest: The First Ascent (Rider).