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Available now on the documentary from the BBC World Service.
The distinct musical genre of Amapiano can be heard in clubs and parties all around the world.
It's a sound born out of the unique cultural identity of South Africa.
I am legendary Chris and I'm going to take you on a journey of exploration
as we dive into the history of the music.
Listen now by searching for the documentary wherever you get your BBC podcasts.
In a basement on the east coast of the United States stands an airtight box,
a little over six feet high and seven feet long.
It's made of copper and lined with zinc and wood with one small glass window onto the outside world.
Inside sits a young man who can just about stand and lie down,
but his cell isn't wide enough for him to stretch out his arms to his sides.
He's supplied with oxygen, food and water,
but he's subjected to gruelling physical and mental exercises that leave him utterly exhausted.
And he can't leave for almost two weeks.
It sounds like torture, right, or something out of a gripping psychological thriller.
In fact,
this man was a volunteer taking part in a scientific experiment and this unforgiving chamber at its willing prisoner helped to create something that's fundamental to the way many of us view food and our own bodies.
I'm Bridget Kendall and on this week's episode of the Forum,
our subject is the calorie, an invisible force that shapes the way we feed ourselves.