| Athlete |
Nation(s) |
Sport(s) |
Role(s) |
Era |
Notes |
| Alfred Grisar |
 BEL |
POL |
Olympics |
1920 |
Co-owner of Koko, who ran in 1928 |
| Freddie Guest |
 GBR |
POL |
Olympics |
1924 |
Co-owner of Koko, who ran in 1928 |
| Eddie Harty |
 IRL |
EVE |
Olympics |
1960 |
Winning jockey aboard Highland Wedding in 1969 |
| James Hennessy |
 FRA |
EDV |
Olympics |
1900 |
Owned Lutteur III, who won the race in 1909 |
| Harry Llewellyn |
GBR |
EJP |
Olympics |
1948—1952 |
Rode as a jockey aboard Ego in 1936 and 1937, finishing 2nd and 4th respectively |
| Fon, Marqués de Portago |
 ESP |
BOB |
Olympics |
1956 |
Rode as a jockey in 1950 and 1952 |