In the AF/MF tab of the X-H1’s menu is the AF-C Custom settings, allowing you to customise the response of the continuous autofocus (AF-C) system.
These comprise five Sets of settings along with a sixth that is provided for the photographer to customise. Each of the Sets specifies values for Tracking Sensitivity, Speed Tracking Sensitivity and Zone Area Switching. These are designed to take control over how quickly the camera adjusts the focus when the subject distance or speed of movement changes, or prioritise the focus area. A good understanding of the subject and the situation is needed, but the menu screen displays typical uses for each Set.