YouTube star Calfreezy has tried a week in the life of KSI, including five-kilometre runs, intense physio sessions and eating a ton of oats for breakfast.
Everything KSI touches seems to turn to gold, whether that be acting, boxing or music.
But what is it about him that makes him so successful?
Well, Calfreezy decided to live like his friend for a week to try and find out.
KSI sorted Calfreezy out with his workout plan to gain an insight into what his gruelling fitness regime looks like during training camp.
Being one of the biggest internet stars on the planet undoubtedly has its perks - but it also means he hardly has any spare time either.
So it's no surprise then that his schedule is rather crazy.
On a typical day he gets out of bed at 8am, has a shower and has his first meal of the day at 9am.
VIDEO: A week in the life of KSI
Check out the video below...
He then works out from 10am-1pm - when most people are sat behind a desk in the office.
After his workout he has his lunch at 1pm then it's time for some much-needed R&R at 1:30pm.
He also sometimes mixes it up a bit here and there with a boxing session at 3pm and 4pm respectively.
At 4pm he films a video for his YouTube channel before having dinner at 5pm.
Then KSI takes a two-hour break to let his body recover from the busy schedule.
KSI left FaZe Temperrr out for the count
More rest and relaxation takes place until 7pm when he goes for a run which in his own words "has to be at least 5k."
He also makes sure that he is in bed by 11pm everyday so that he can get enough sleep.
Afterwards, Calfreezy admitted that running was 'the worst part of the routine'.
He explained: "The worst part of the routine so far has been the runs.
"I find the running just terrible.
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Calfreezy, KSI, Miniminter and Zerkaa in 2018
"I'm really struggling with the running side of things.
"I just really don't enjoy it.
"As much as I try to, I find it a very lonely experience.
"I enjoy the company of other people, and looking at what JJ does, a lot of it is very isolated.
"You have music, he's up on stage, alone.
"In a boxing ring, it's just him.
"These are things where it really is just him and he has to rely on him and I think when it comes to running it's just a bit lonely."
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