“Yes, she didn't know, she never knew about Harry Potter - I started writing it six months before she died, so that is painful,” Rowling said. “I wish she'd known.

“My mother was a passionate reader, and she would have been excited whatever I did, if I succeeded at anything, but particularly to be a writer, she would have considered that to be a very valuable thing.”

“She always seemed very young,” she said. “She was very fit, she was a non-smoker, non-drinker, and I say all of this because of course then for her to be diagnosed at 35 with an illness that would kill her was just the most enormous shock to us and everyone who knew her.”

“I was a teenager, but yes, it had the most enormous impact on our family life, and my mother, by the time she was diagnosed, she was quite ill,” recalled Rowling.

“She had been showing symptoms for a few years and didn't know what they were, so by the time she was diagnosed, her health was deteriorating, so it wasn't just the spectre of the unknown, it was dealing with the daily reality of somebody who's starting not to be able to walk as well as they had, and for such an active person that was a real privation.”

‘I grew up in a house where my father and male relatives were all football supporters and I was used to watching football on TV.’

She added: ‘It’s not until I married a Scot that I was taken – not entirely willingly – to the rugby. And then I accidentally ended up enjoying the rugby. So there is hope for you. You can definitely convert, ha ha!’

She said: ‘I was very taken aback by the difference in a rugby crowd and a football crowd. As a woman, being at the rugby is quite a welcoming place. Whereas I can remember going to football matches in London and feeling quite intimidated. So that was obviously a welcome change.’

She added: ‘What is happening on the [rugby] pitch is horrible and violent and dreadful but meanwhile you are sitting with a lot of people who will happily buy you half a pint and a pie and chat away to you even if they are supporting the opposition – and I found that rather enjoyable.’

Rowling also contrasted the attitude of rugby players with that of footballers, who were willing to cheat or feign injury.

She said: ‘[Rugby players] don’t dive. I think that is rather a nice difference between rugby and football. You do start to respect them for literally soldiering on when they are in terrible pain. It’s quite the reverse of football.’

She said: ‘Rugby in Scotland was a farmer’s game, a farm lad’s game more than a public school boy’s game, I would say.’

Rowling, who will look at women’s rugby in Scotland, said: ‘I have never played myself and I cannot see myself playing rugby ever.

‘But I do really take my hat off to the women who do. And I am kind of fascinated by why women play. I had a friend at university who played and she played very very well. She loved the physicality of it.

‘I am very interested in people who genuinely feel satisfied by putting themselves through 80 minutes of utter hell.’

Speaking on Woman's Hour on BBC Radio 4 today, Rowling, 48, says she decided to "tidy myself up a bit" when people began to comment on how she looked when she first began to appear in the public eye after the success of her Harry Potter books.

"I would be a liar if I said I don't care," she admits on the programme, which she is also guest-editing.

"I found it very difficult, when I first became well-known, to read criticism about how I looked, how messy my hair was, and how generally unkempt I looked.

"I did tidy myself up a bit. But I do often resent the amount of time it takes to pull yourself together to go on TV."

Rowling is the first guest editor in Woman's Hour's 67-year history and in the programme she will highlight the plight of the world's eight million children forced to live in institutions.

She is also tackling why Scotland has the highest number of multiple sclerosis sufferers in the world, and her loves of rugby and shoes.

But speaking to presenter Jane Garvey she also argues women are under greater pressure than their male counterparts in terms of public image.

"It must be so nice to be a man and just think 'which of the three suits will I wear today?' and nobody would say a thing.

"With us it's our weight, our clothes, how we're ageing, our hair."

Rowling says she wishes she was strong-willed and didn't care how others see her, but describes herself as "weak-willed".

Introducing the segment, she said: ‘There are far more important things in life than shoes. But having said that, I like shoes and I have often wondered in a vague way why women are so obsessed with this particular item of clothing.

‘And I think it is undeniable that probably shoes do come first in the most mythologised, fetishised item list, I’d say.

‘So I thought this was a great opportunity to investigate that, and I thought how often shoes turn up in stories and fairy tales and why is that. What is the power and myth of the shoe?’

‘Naturally. I’m not a pumps girl, I’m not a sensible flats girl’, Rowling, 48, said before speculating on ‘the power and myth of the shoe’, which she described as the most ‘mythologised, fetishised’ fashion item of all.

She told the audience: ‘My first award was a Nibbie, but that night I was wearing much, much cheaper shoes.’