Anthony Joshua has donned an altitude mask as he continues to ramp up his training regime with less than a month to go until his showdown with Wladimir Klitschko.
Still seeking ways to rise his performance levels ahead of one of the most anticipated title bouts of the year, Joshua drew comparisons with Bane, the villain from the Batman comic and movie series.
In a video posted to his Instagram, the IBF world heavyweight champion is shown wearing the mask while going through his intense workout regime – including press-ups, pull-ups, bouncing a medicine ball and lifting kettle bells.
Arguments still rage over whether these elevation masks, which are intended to simulate the restricted oxygen intake of training in the thinner air of high-altitude, but Joshua isn't taking any chances.
The 27-year-old from Watford has a perfect record of 18 wins and no defeats with 18 knockouts in his professional career thus far, having come a long way since his super-heavyweight gold medal at the London 2012 Olympic Games.
However, Joshua has never had to box past the seventh round, and his upcoming opponent has cast doubt over his aptitude for boxing.
"I have a lot respect for Anthony and what he's doing," said Klitschko earlier this week. "His commitment and physical ability – he can box, he can lift weights, he's strong. He can be a crossfit world champion actually.
"He has great capability. I believe he could do it. There are a lot of boxers doing it, but crossfit is not boxing.
"He has these big muscles that give him confidence. He wants to demolish people right in front of him. Those muscles give him a lot of confidence."
Klitschko, 41, dominated the heavyweight division for nearly a decade before a points-decision loss to Tyson Fury in Germany in 2015.