| Name | Team | Event Name |
|---|---|---|
| Oliver Cecala | Hikers4Life | Hike Yosemite |
| Oliver Penn | TCS New York City Marathon | |
| Olivia Petrillo | The Running Joke | Bank of America Chicago Marathon |
| Olivia Sahaydak | Bank of America Chicago Marathon | |
| Olivia Spitznagle | Isabella and Olivia | Bank of America Chicago Marathon |
| Olivia Tate | Bank of America Chicago Marathon | |
| Olivia Vertin | Bank of America Chicago Marathon | |
| Orion Ramroop | TCS New York City Marathon | |
| Osayre Gomez de Peralta | United Airlines NYC Half | |
| Oscar Arnold | America's Most Beautiful Bike Ride |