What can cycling do for your health?
In early July the world's greatest cycling race, the Tour de France, will begin in Yorkshire.
Sir Bradley Wiggins, Chris Froome and Mark Cavendish will be among those hoping to take on the most gruelling event in sport - covering more than 2,000 miles in three weeks.
But how does the level of fitness of these elite athletes compare with the growing army of middle-aged men in Lycra - or Mamils - who can be seen out riding every weekend?
The BBC's medical correspondent Fergus Walsh is one of those middle-aged riders.
He went to the School of Sport and Exercise Sciences at the University of Kent to have his cardiovascular health tested, to assess whether all those hours on the bike have been useful.
The test was carried out by senior lecturer Dr James Hopker.