But are some records unbeatable? The Olympic Games in Paris this summer are likely to bring amazing performances, some of which may never be beaten.
This could be the year… of a two-hour marathon

Glossary
Chicago - One of the biggest cities in the USA.
Marathon - A very long running race, lasting for 26.2 miles.
Coach - Either a type of bus, or a person who trains an athlete.
Kenya - A country in East Africa with a population of nearly 54 million people.
Roger Bannister - An English neurologist and athlete. He died in 2018.
Expert - Someone who knows a lot about a particular subject.