But are some records unbeatable? The Olympic Games in Paris this summer are likely to bring extraordinary performances, some of which may never be surpassed.
This could be the year... of a two-hour marathon
But are some records unbeatable? The Olympic Games in Paris this summer are likely to bring extraordinary performances, some of which may never be surpassed.
<h2 class="wp-block-heading eplus-wrapper">Distance persistence</h2>
Two weeks before the Chicago marathon in October, Kelvin Kiptum fell ill. According to his coach, Gervais Hakizimana, it left his body weak: "What worsened everything was the acute tonsillitisWhen the tonsils are swollen and painful, usually caused by a viral infection. , which had made his neck swollen." But this, said Hakizimana, was no excuse to miss the 26.2-mile race: "I had to handle the situation and told him that he can't fail to compete."
So the 23-year-old Kenyan ran - and set a new world record of 2 hours 35 seconds. It was a whole 34 seconds faster than the record set by Eliud Kipchoge the previous year.
The achievement was extraordinary. It was only the third marathon Kiptum had ever run. He had averaged 13.04 miles per hour.
He and Kipchoge both come from poor backgrounds in Kenya. Kiptum herded his family's cattle as a young boy and started racing his friends barefoot along forest trails. Kipchoge ran two miles to school every day; when he met his coach at 16, he was delivering milk on a bicycle.
Until Kiptum emerged as a rival, Kipchoge's supremacy in the marathon seemed assured. His run of 2 hours 1 minute and 39 seconds amazed commentators:
"The lower the world record gets, the harder it is to be broken, and the less it should be broken by," LetsRun.com noted. "Yet Eliud Kipchoge just broke the world record by more than any man in the last 41 years."
Ever since record-keeping began, people have wondered where the limits of human achievement might lie. Until Roger BannisterAn English neurologist and athlete. He died in 2018. ran a mile in under four minutes, some believed it was physically impossible.
The record for the marathon has been cut by almost a third since 1908, when Johnny Haynes ran it in 2 hours 55 minutes 18.4 seconds. Now beating the 2-hour mark is the greatest goal in athletics.
Several things have contributed to faster times. Today's athletes are better trained than in Haynes's day. They have better equipment and better nutritional advice.
Eliud Kipchoge has in fact already run a marathon in under two hours in Vienna - but not in a way that is officially recognised. Other athletes took it in turns to run in front of him in a wind-blocking formation, a laser projected from a car showed them the ideal pace, and a cyclist rode alongside to hand him energy drinks. One expert compared it to running down a mountain.
Data scientistA new type of data expert. Data scientists work with businesses to understand data and help to convert it into action that will improve a business or organisation's performance. Simon Angus has constructed a graph showing changes to the marathon record over the past 65 years. He estimates that the two-hour barrier will be broken in March 2027 - but that no one will ever run faster than 1 hour 55 minutes and 40 seconds.
In an article for Sports Brief, Martin Moses lists five existing records that may never be broken. One is Uwe Hohn's 104.8m javelin throw in 1984: no one else has ever reached the 100m mark.
Moses reckons that Usain Bolt's 100m record (9.58 seconds) and Florence Griffith-Joyner's (10.49) are both safe. He also lists Jarmila Kratochvilova's 800m record (1 minute 53.28 seconds) and Marita Koch's 400m record (47.6 seconds).
But are some records unbeatable?
Yes: Logic tells us that there are limits to what the human body can manage. No on will ever run 100m in 5 seconds, so there must be a point at which nothing more can be shaved off the fastest time.
No: Existing records have been set by extraordinary athletes - but it is possible that even more extraordinary ones will emerge in the future. And they will be helped by ever-improving sports science.
Or... Record-breaking requires perfect conditions - Kiptum's run in Chicago was helped by cool temperatures and dry, cloudy weather. Climate change means they will become much harder to find in future.
Tonsillitis - When the tonsils are swollen and painful, usually caused by a viral infection.
Roger Bannister - An English neurologist and athlete. He died in 2018.
Data scientist - A new type of data expert. Data scientists work with businesses to understand data and help to convert it into action that will improve a business or organisation's performance.
This could be the year… of a two-hour marathon

Glossary
Tonsillitis - When the tonsils are swollen and painful, usually caused by a viral infection.
Roger Bannister - An English neurologist and athlete. He died in 2018.
Data scientist - A new type of data expert. Data scientists work with businesses to understand data and help to convert it into action that will improve a business or organisation's performance.