Cardiac arrest in fitness class caught on camera
Mark Kingsland was sparring in a fitness class when he went into cardiac arrest, and it was caught on camera.
Now he has recovered he spoke to presenter Victoria Derbyshire and the man who gave him life-saving CPR.
Watch the Victoria Derbyshire programme on BBC Two and BBC News Channel, 10:00 to 11:00 GMT - and see more of our stories here.