SHIFT

Horse Run / Gallop (SHIFT)

WhenMounted Horse Racing

ActionRun (On Horse)

Record

Action: Run (On Horse)
Input: SHIFT
When: Mounted Horse Racing
What it does: Accelerates your horse into a full gallop; speed and stamina drain scale with your rolled Horse Stats.
Tip: Feather SHIFT on steep uphill shortcuts so you do not bottom out stamina before the straightaway.

PC keys are the defaults. Console and mobile use the matching on-screen button.