A PureGym personal trainer has faced racist abuse after posting a "slave" workout online.
Matt Simpson shared the routine on Facebook to mark Black History Month, however he received a huge backlash over the post.
He apologised "wholeheartedly" for calling the exercise regime 12 Years of Slave in reference to the Hollywood blockbuster.
His post on the PureGym Luton and Dunstable Facebook page said "slavery was hard and so is this".
Mr Simpson has now spoken out about the "heartbreaking" trolling he has since received online, much of which focuses on him being black.
The personal trainer said he has been called the N-word and other racist words, with some of the vitriol even coming from black people.
He told Radio 1 Newsbeat : "Some of the abuse has been things I am ashamed to say out loud. The most common theme has been in reference to slavery, and my skin colour.
"I have been told 'keep to your white company' and 'we're going to take his black card off him.
"It's heartbreaking when you look at the sender and the sender resembles you."
He added that there was "no word" to describe how this makes any person of an ethnic minority feel.
The trainer said the mental impact of the abuse has affected his appetite and he has stopped going out as much.
Mr Simpson warned that trolling can send people into a "spiral of negativity", adding he does not feel as lively or as positive as he used to.
PureGym has apologised for the post and launched an investigation into it.
A spokesman for the company said: "PureGym apologises unreservedly for a post regarding Black History Month that was made today by our gym in Luton & Dunstable.
"This post was wholly unacceptable, was not approved or endorsed by the company and was removed when it was brought to our attention. We take this matter extremely seriously and are urgently investigating how and why this post was made.
"Thank you to those people who commented on this post and for raising this with us."
