Image copyright PA

Agatha Christie read 200 books every year, while Facebook founder Mark Zuckerberg gets through a book a fortnight. President Theodore Roosevelt read a book a day, and increased this to two or three when he had a quiet night. But how can mere mortals get through more?

Harriet Klausner - a school librarian who died last year - was either one of history's greatest speed-readers or someone somewhat economical with the truth.

Klausner clocked up a staggering 31,014 Amazon book reviews, sometimes reading six books a day. But not everyone could accept that feat, with a group of critics forming to debunk her claims.

The speed-reader defended herself by pointing out that some of the romance novels she reviewed were so short and simple they could be polished off in an hour. And Klausner offered a simple explanation for her enthusiasm: "If a book doesn't hold my interest by page 50, I'll stop reading," she told the Wall Street Journal.

Image copyright PA

Klausner's achievements may seem to be in the realm of fantasy but many of us do wish we could read more. Finish more books. Cram in more knowledge. Appreciate more literature.

Distracted by TV box sets, football matches and Twitter trends, we seem to find it increasingly difficult to fit reading into our lives.

John Sutherland is an author, book critic, columnist and emeritus Lord Northcliffe Professor of Modern English Literature at University College London.

In 2015 he read approximately 150 books.

"Quite a lot," he suggests, "probably as many books as I had hot dinners." Using a tablet enables Sutherland to skip through pages at lightning speed. "That way you don't have to rely on a dampened forefinger - and the risk of giving the next reader tuberculosis," he laughs.

Image copyright Alamy

A professional reader's livelihood depends on their ability to race through words. Last year Sutherland finished a new book approximately every 2.4 days. "I turn four pages at a time if I have to," Sutherland says, "whereas most people like to enjoy their reading. Even I tend not to read more than one book a day… unless there is a gun pointed at my head."

The time it takes to read a book, particularly a dense classic like War And Peace, currently the basis for a relatively brief BBC TV adaptation, can be off-putting.

Image caption The BBC's War And Peace adaptation - 1,000 pages, or six hours on TV?

As a schoolboy, Tony Buzan was given a secret speed-reading test. He was pleased with his score of 213 words per minute. "I thought, wow, I must be a pretty fast reader. But then I asked a girl in my classroom and she had scored over 300. I was crushed."

Buzan decided to improve his skills. He practised speed-reading at home and researched the physics of the eye, as well as learning about fixation (also known as eye focus) and chunking (grouping words together so they can be read as a single chunk).

Buzan discovered that he could read more quickly after physical exercise. Before long, he had doubled his reading speed.

Now a speed-reading and memory consultant, Buzan believes the number of books we read is important. "Instead of reading, say, 1,000 books in my lifetime," he tells me, "I might now read 2,000. And that could change my life."

Tony Buzan's tips for reading quickly

Image copyright PA

Learn how to use your eyes to read faster

Become physically fit, to give your brain more oxygen

Learn how to memorise chapters and even whole books

Read about the brain and its workings

Form a speed-reading and studying team with friends

If you take the often-cited average reading speed of 300 words a minute, the average reader might take about one minute to get through a page. To get through a 300-page novel a day, the reader would have to set aside 35 hours a week.

"There are only so many books I can read in my lifetime and I am not going to waste my time on rubbish," protests columnist and Sunday Times book reviewer Jenni Russell. She thinks we become more selective with age.

My advice is to get bored - my early life was very boring, and reading was a good way of filling in great tracts of tedious time John Sutherland, Literature professor

"When we are young we have an intense curiosity about other people, how they think and feel, their psychology. Now a writer has to have exemplary skill or insight to hold my attention." As a child, Russell read as many as 20 books in a week. Now she reads three a month.

What is the best way to approach a year of reading?

"My advice is to get bored," says John Sutherland. "My early life was very boring. Reading was a good way of filling in great tracts of tedious time."

Russian revolutionary Leon Trotsky also capitalised on boredom. During two years in prison he read from morning until night, tackling classic European fiction, Darwin's studies and Lenin's theories of communism.

Image copyright Getty Images Image caption Leon Trotsky

Former Dorchester Prison literacy tutor Ginny Williams-Ellis founded the charity Read Easy to help people who are unable to read at all. "Books are a very low priority for the people we work with," she explains. "They are complete beginners - their motivation is learning to read shopping lists, tin labels, newspapers, the words that appear in everyday life."

The charity runs one-on-one sessions, similar to the government-funded lessons held in prisons. "Quite of lot of people get excited once they have learnt to read. We worked with one lady, a hairdresser, who was a complete beginner and now reads a romance novel every night."

Russell understands that captivation: "In our lives we only see the surface of people. Fiction takes us into the heads, the thoughts, the motivations of other people. Novels take us to places that we would never otherwise see. Reading can have an astonishing effect on us."

Image copyright PA

Literary coach and journalist Glynis Kozma advises people to carve out time in their schedules: "Rather than thinking that you need to sit down and read for an hour at a time, try to make use of small amounts of time," she suggests. "Read for 20 minutes while you are waiting for dinner to cook. Use every 15-minute gap."

Kozma aims to read one book a month, although she sometimes misses her target. "I think a lot of people feel guilty about reading," she says. "We are all so busy and have so much going on in our lives that we find it difficult to justify taking the time out."

Subscribe to the BBC News Magazine's email newsletter to get articles sent to your inbox.