If you want to measure an athlete's popularity, then Twitter is a great place to start.
Of course, not every athlete is on Twitter, but the majority of big-name sports stars are.
We've produced a list of the most-followed athletes on Twitter, complete with their follower numbers, number of tweets and how many people they follow back.
All statistics are current at the time of writing, although it must be remembered that the numbers change on an hourly basis.
Despite the fact ten athletes feature on this list, it may come as a surprise to discover that only two sports are represented.
Click next to see the world's most popular sports stars - based on Twitter followers...