think through the split
The axe head and speed and focus and keeping the edge straight to the wood does the work. Your hands merely steer this operation. Steer more, power less. Speed more, aim better. Finesse and focus is easier on the mitts than grunt swings.
To me, good splitting is like any other sport. Ya, most anyone can grab a whatever with some sort of edge to it and mangle a chunk of wood into pieces, but the better you get at it the less effort it takes to do even more work. And the less it beats on you, hands included.
I also cull the herd fast. I have all the wood I want, so if a particular piece starts to give me fits, it gets thrown onto the obnoxious/bummer pile. I cull it till later. Two months (or so) later I'll go through the pile again. Amazing what an additional two months of drying will do for you, more cracks to aim at, etc.
Anyway, I think of it as way more a sport/skill than "work" and for some reason it keeps getting easier the more I refine my technique. Especially with the fiskars.
I must say though I am dissatisfied with the fiskars sharpener. I have some brand X one that works better, but even that leaves some meat on the platter. I am thinking I might invest in a rouge wheel instead..maybe. There's a huge difference with the fiskars between normal "sharp" and OMG if your finger gets within an inch you get sliced sharp. The latter will really split some wood.