The 33-year-old undertook a 30-day challenge to do 100 sit ups per day – no mean feat when his starting weight was 28 stone/175kg.
The Beast posted a YouTube video during lockdown as he attempted to shed excess weight and gain fitness ahead of the fight, which is due to take place in Las Vegas on September 18, although a venue is yet to be confirmed.
He said: “I'm going to start dropping bodyweight and getting fit.
"I'm going to attempt 100 sit ups. I don't think I'll get there, but it's a building process... Rome wasn't built in a day!
"So, I'm going to try and do 100 sit ups every day, a little bit of boxing work and then I'm going to go for a bike ride and start dropping the pounds.
"I am currently today 385lbs, which is 175kg, or just under 28 stone in English terms. I'm going to document this journey for you guys to see."
The video shows Hall undertaking his challenge everywhere from his back garden to the kitchen floor.
On day five, he said: “It’s hard, it’s really hard. After 40-45 reps I really have to slow it down. Today I made it to 65. It’s getting easier, and I feel the weight’s coming off quite quickly.”
While he visibly struggles in the opening days, by the final day, his abs are visible and despite his size, The Beast is rocking a six pack.
As the challenge comes to a close, he said: "I'm currently 166 kilos, so I anticipate I've lost around about eight kilos, so about a stone and a quarter and I feel great for it.
"I feel absolutely fantastic. All the excess fat's gone, my abs have come out massively, so I'm really, really happy with the results."
Hall vs Bjornsson
The pair’s long-running rivalry is set to come to a head in September, with both men having won World’s Strongest Man – Hall in 2017, and Thor taking a prize year later.
The Icelandic star – well known in popular culture for starring as The Mountain in Game of Thrones – holds the unofficial deadlift world record after lifting 501kg in his home gym.
While this breaks the official record of 500kg – held by Hall – it is not recognised by the strongman authorities because it wasn’t achieved in a competition setting.
However, it certainly added fuel to the fire between the pair.News Now - Sport News