Tokyo Olympics: The ancient therapy of cupping is why athletes are covered in dark round splotches

Just what are all the dark round splotches covering many of the swimmers at the Tokyo Olympics?

It’s not a strange disease or love bites. It’s a process known as cupping — and it’s becoming more and more popular among top athletes.

In fact, Aussie champion swimmer Kyle Chalmers is covered in splotches — and they appear to be growing in number with every appearance he makes in the pool.

Cupping is an ancient therapy mostly used in Middle Eastern and Asian countries.

It involves placing warm suction cups on the skin to create a vacuum — leaving dark round splotches on the skin.

The process is believed by some to increase blood circulation, relieving muscle tension and promoting cell repair, despite there being no medical evidence that cupping has any benefit for athletes.

However, it hasn’t stopped current and former Olympians from taking up the ancient practice.

Retired American swimming legend Michael Phelps used the technique while in competition, saying he relied on cupping to heal sore muscles.

And it’s not just confined to athletes — celebrities including Gwyneth Paltrow and Jennifer Aniston have previously espoused their support of the dark splotches.

Robert Glatter, an emergency physician at Lenox Hill Hospital in New York and a former sideline physician for the New York Jets, told USA today that there are only a handful of studies on cupping but they were poorly done.

But he said it did not mean cupping was useless.

Dr Glatter said it could work as a placebo, giving elite athletes a psychological boost.