African-American Tommie Smith won 200m Olympic gold at the Mexico City Games in 1968 but caused controversy by making a 'Black Power Salute' during the awards ceremony. It was a protest in the face of on-going black civil rights issues.
Smith, who will watch Tyson Gay attempt to break his 200m world record over a straight course, in Manchester on Sunday, explains what led him to make one of the most political statements the Olympics has ever seen.
Watch more of this interview on BBC Two on Sunday afternoon.
And there is another chance to watch a 60-minute film, 1968 Olympics: Black Power Salute on BBC Four on Sunday at 1900 BST.
SUMMER OF ATHLETICS BEGINS
Diamond League first meeting, Doha
1700-1900 BST live on BBC Red Button and BBC Sport website (UK users only)
Michael Johnson meets Usain Bolt: The Fastest Man Who Has Ever Lived
1710 BST on BBC Two and iplayer for seven days after (UK users only)
Great Manchester Run and Great City Games
1000-1130 BST and 1630-1800 BST live on BBC Two and BBC Sport website (UK users only)
19 May: Usain Bolt's season debut at Daegu Pre-Championships, South Korea 1055-1345 BST live on BBC Red Button and BBC Sport website (UK users only)