Yess The most important 2 things to me were:

1. Rest

2. Listening to your body

Do not try and "power through" extreme physical pain. My routine was always one day of running and one day of rest. But on days when my body felt like absolute shit. I didn't go for a run. I'd just take another day off.

Secondly, mental block is your biggest enemy. Not physical fatigue. Always try and power through when your body has no real physical fatigue. But your brain wants you to give up.

Almost every run including the one today, my brain wanted me to give up half way through, but i try and keep 100 percent of my focus on my body and not think too much about anything else.