Demonic ones! I hope you are feeling the spring coming on. I’d like to suggest that you sneak in a couple hill reps in an upcoming run. When you come to a nice hill (not too long, not too steep) that’s maybe 100 yards, stop and prepare for 3-4 reps. Run up strong but not hard, walk back down, and repeat. You’ll be amazed at how your stride feels on the rest of your run. Just don’t push too hard right now.