In athletics, that would be the current women's 100 meter dash record set by Florence Griffith-Joyner on July 16, 1988.
Ralph Metcalfe and Eddie Tolan held the men's 100 meter dash world record at 10.38 seconds for almost 16 years (August 1, 1932 through July 9, 1948).
Jim Hines held the men's 100 meter dash record at 9.95 seconds for almost 15 years (October 14, 1968 through July 3, 1983).
usain bolt
one hundred twenty one
David Ambler - 100m record of 10.41s
There is no Guinness World Records listed specifically for longest time standing, however, St Simeons pole-sitting feat (c AD 521-97) is the longest-standing world record for an individual chronicled. Suresh Joachim holds the Guinness World Record for standing on one leg. He managed this for 76 hours and 40 minutes.
Paul Nash 100m record was in 1968
Kristy Coventry from Zimbabwe rewrote the world record for the women's 100m breastroke, and the record is 58.77 seconds.
The men's long jump world record set by Mike Powell in 1991 is the longest standing athletics world record. He jumped 8.95 meters (29 feet 41⁄4 inches) at the World Championships in Athletics in Tokyo.
The men's long jump - 8.90 meters set in 1968 at Mexico City.
Gerald Mathers for the 330M dash - last run in 1912. While the answer above is right for the Modern Olympics, if you wanted to be really pedantic, the longest standing record for the Olympic games in their history is Nero's for chariot racing.
1.5
9.91
10.49s