Editing run scene

I’ve created a running sequence but the character moves across the screen far too quickly. What is the best way to increase the exposures? Should I use the timeline and/or the xsheet. When I select all of the body parts on the xhseet and select increase xposure the character is no longer visible in the camera. Any suggestions? Does the position of my keyframes and when I set keyframes play a part in this matter?

You are working in pure drawings or symbols in main timeline?
If you are working directly in drawings you can increment the exposure selecting the frames and right click, exposure/set exposure to 1-2-3 or more.
If you are working with timeline, always overwrite the exposure, but if you work in the x-sheet you can decide if overwrite or insert the exposure (insert push down the rest of the action).
With symbols his drawings contained in the symbol box are linked to the assigned symbol cell, you can extend the exposure in the cells that are linked with drawings, but if his selection not contains drawings, you cannot see anyting in this exposure. Then for example, if his symbol box contains five drawings: 1-2-3-4-5, first you need assign a basic exposure in the symbol layer in timeline (swapping), select the frames that are linked with drawings, basic example, the first five cells of the symbol, an proceed to set the desired exposure. If the layer symbol dragged to main timeline is showed filling all the scene length in timeline, these exposure contains blank cells numbers into the symbol itself. Adjust the brackets of the symbol timeline to the actual drawings frames (you only have five drawings to swap, in the example), then you need swap the rest of the exposure to involve these five drawing numbers in the desired order and exposure. Hope that I be clear exposing.