hardset nipples wrote:
What's the purpose? For building strength, incline. For faster turnover, decline. General speed maintenance, flat. You're going to benefit if you're doing these right, regardless, so you're probably worrying about this detail too much.
This is the answer. Know the purpose of what you are doing in training, and don't overthink it.
I like doing slight decline (say 2% max) strides or pick-ups on easy days. I find it helps if you're feeling sluggish or tired from a previous workout to get going. For workouts where I am trying to improve speed or power, I prefer flat or uphill (as steep as possible while still being able to run properly).
Ultimately though the real decider is the logistics of where I'm running. Work with what you got.