@baldwinbeckett As others are pointing out, nothing is ‘better’ and that’s basically true.
If you are asking STRICTLY about calorie burning. I believe, and I might be wrong about this, so if anyone is actually an expert, please correct me, but: it’s really only the distance that matters, because the human body is REALLY good at homeostasis. So if you walk a mile, or run a mile, it will approximately be the same relative calories burned. This might seem outrageous, but if you think about it, if you run that mile you will only be running for a few minutes. If you walk it will, of course, take significantly longer. Increasing incline WILL increase calories burned, but it will be uniform across the board, whether you’re walking or running.
I never mess with the incline unless I am running a walking “program” on the treadmill (which I do, a lot) and it adjusts the incline for me without me fucking with it. All it does is raise your heart rate. Which is fine. It’s great for your metabolism and does burn more calories than no incline.
Anyway, I do both walking and running. On cardio days I run fast for 1/2 hour (no incline) and then cool down by walking for 1/2 hour. I work in progressive overload into the running portion by upping my speed by 0.1 mph every week. I am currently at a 7.6 mph run, although I recently had to dial that WAY back to 7.0 because I didn’t run while I was recently sick, so I’m working my way back up to 7.6
On non-cardio days, I just walk for however long I want to post-lifting. I don’t even track it. Usually with one of those programs you can select on the treadmill that I spoke of earlier.