De 27-jarige Brittany woont in New York en komt dagelijks te laat aan op haar werk na een nachtje stappen. Wanneer ze voor een kleinigheid een dokter bezoekt krijgt ze in plaats daarvan een waslijst aan diagnoses te horen. Opeens wordt ze gedwongen over haar levensstijl na te denken, waarna ze besluit te beginnen met hardlopen.
Nee, helaas is Brittany Runs a Marathon nog niet beschikbaar op Netflix in Nederland.
| Visual Effects | Alex Noble | Visual Effects Supervisor |
| Art | Lindsay Stephen | Set Decoration Buyer |
| Sound | Ric Schnupp | Sound Re-Recording Mixer |
| Sound | Ric Schnupp | Supervising Sound Editor |
| Production | Laura Rosenthal | Casting |
| Directing | Thomas Fatone | First Assistant Director |
| Directing | Kim Thompson | Second Assistant Director |
| Production | Jolian Blevins | Unit Production Manager |
| Sound | Winslow Bright | Music Supervisor |
| Directing | Paul Downs Colaizzo | Director |
| Writing | Paul Downs Colaizzo | Writer |
| Production | Matthew Plouffe | Producer |
| Production | Tobey Maguire | Producer |
| Production | Margot Hand | Producer |
| Camera | Seamus Tierney | Director of Photography |
| Editing | Casey Brooks | Editor |
| Production | Jillian Bell | Executive Producer |
| Art | Naomi Munro | Art Direction |
| Art | Erin Magill | Production Design |
| Art | Kim Fischer | Set Decoration |
| Costume & Make-Up | Stacey Berman | Costume Designer |
| Production | Paul Downs Colaizzo | Executive Producer |
| Sound | Duncan Thum | Original Music Composer |
| Production | Jolian Blevins | Co-Producer |
| Production | Richard G. Weinberg | Executive Producer |
| Production | Padraic 'Paddy' Murphy | Associate Producer |
| Production | Maribeth Fox | Casting |
| Costume & Make-Up | Scott Hersh | Makeup Department Head |
| Costume & Make-Up | Dennis Polanco | Hair Department Head |
| Costume & Make-Up | Michael Zambrano | Key Hair Stylist |
