dunno what light comes off Your head?
I used quite some headlamps on my helmet for night trail biking (additional light). Now its a Streamlight Argo HP, modded with SSC and 18650.
With a rechargeable Li-Ion (size 17650), even in original state, output is quite sufficient for running.
And there are quite other makes.
imho an additional handheld is a good idea, because the headlamp gives no shadows. Knee sized rocks look like a flat piece of stone till one hits it.
L2D-CE because of Your runtime requirement