12 or more years between first and last olympic appearence:
Veronica Campbell-Brown 2000 - 2016
Usain Bolt 2004 - 2016
Evelyn Ashford 1976 - 1992 (boykott 1980)
Marlies Göhr 1976 - 1988 (boykott 1984)
Ezekiel Kemboi 2004 - 2016
Allyson Felix 2004 - 2016
Mamo Wolde 1956 - 1972
4 or more appearences in same running event:
Paul Martin (5: 1920-1936 in 800m)
Willie Davenport (4: 1964-1976 in 110mH)
Emiel Puttemans (4: 1968-1980 in 5000m)
Pietro Mennea (5: 1972-1988 in 200m)
Evelyn Ashford (4: 1976; 1984-1992 in 100m + 4: 1976; 1984-1992 in 4x100m) - boykott 1980
Carlos Sala (5: 1980-1996 in 110mH)
Johnny Gray (4: 1984-1996 in 800m)
Merlene Ottey (6: 1984-2004 in 100m + 6: 1980-1996; 2004 in 200m + 6: 1980-2000 in 4x100m)
Pauline Davis-Thompson (4: 1984-1992; 2000 in 200m);
Branko Zorko (5: 1988-2004 in 1500m)
Letitia Vriiesde (5: 1988-2004 in 800m)
Sandie Richards (4: 1988-2000 in 400m + 5: 1988-2004 in 4x400m)
Mary Onyali (5: 1988-2004 in 200m)
Colin Jackson (4: 1988-2000 in 110mH)
Maria Mutola (6: 1988 - 2004 in 800m)
Gail Devers (5: 1988-2004 in 100mH)
Derartu Tulu (4: 1992-2004 in 10000m)
Haile Gebrselassie (4: 1996-2008 in 10000m)
Antoni Bernadó (5_ 1996-2012 in Marathon)
Ezekiel Kemboi (4: 2004-2016 in 3000mSt)
Usain Bolt (4: 2004-2016 in 200m (very soon))
Veronica Campbell-Brown (4: 2004-2016 in 200m + 4: 2000-2012 in 4x100m)