Both men appear to be doing all they can to grab an extra edge ahead of the fight, and Usyk took to social media to reveal a common – but uncomfortable – technique to do just that.

He shared a post-training photo on his Instagram account on Thursday, with fans questioning why he had two devices wrapped around his biceps.

Oleksandr Usyk has shown off his brutal method of putting on muscle ahead of his clash with Tyson Fury

The Ukrainian boasted that ‘the hard work is done’ in the caption of the social media post

The two heavyweights will go head-to-head in a clash to crown the undisputed champion

The devices were belt-like objects that are used to restrict blood flow to the arms, a technique boxers often use to help build muscle.

The bands are known as pneumatic restriction cuffs and the Ukrainian had no qualms about showing them off online.

With less blood flow to the muscles, they therefore receive less oxygen and tire quicker.

Pressure around the limb also leads to pooling of blood in the limbs, which causes hypertrophy, and is only usually carried out by trained professionals.

It causes muscles to swell and get bigger, meaning the boxer is effectively stronger ahead of their fight, which is what Usyk is likely aiming for.

In the photo, captioned: ‘The hard work is done,’ the 37-year-old, who boasts a 21-0 record in professional boxing – including back-to-back wins over Anthony Joshua – can be seen sat on the edge of a ring post-workout.

‘He no longer looks like a blown up cruiserweight,’ one fan commented on the post.

Another added: ‘I feel Fury will lose.’

Fury, meanwhile, impressed fans in showing off his slimmed-down physique ahead of the fight

While Usyk has been looking to put on weight ahead of the bout, Fury has displayed his slimmed-down physique ahead of the rearranged fight.

Although it has been reported that the star eats 6,000 calories a day, he stunned fans with a body transformation in a topless photo shared on his own social media.

Fury, who is defending his WBC belt against Usyk on May 18, shared the snap on the social media platform with the caption ‘Undisputed incoming’ and the date of their fight.