Whenever I get greedy-- no, not whenever--I'm always greedy about running progress-- running shuts me down. Rarely, in fact, does the greed get rewarded-- perhaps intermittently enough to keep trying (Psych 101 taught me something I can't quite recall about intermittent rewards being very powerful), though.
The lesson I know I should be learning: run for the sake of running.
I was out two days ago-- I could barely sustain a jog for a few minutes. (Once, I was able to run a 10k without any walking breaks. But recently I've been sick; less recently, my body has had some significant aches and pains.) During that run/walk, I was constantly battling my internal frustration. I'm not as good as I was. What if I can't get that good again? Sometimes this has felt easy, but it feels horrible now.
The practice of running-- as a long-term pursuit-- is, I think, a game of constantly paying attention and simultaneously not worrying about comparing what you're noticing. I find it hard to consciously try to measure my status (a little faster today, a little farther today) without inviting disappointment when I'm not progressing in a positive direction.
I've written before about running and patience-- I'm thinking that humility is part of that lesson too. Not only do I need to be patient with myself-- if I'm interested in the long-term practice of running, then I need to not be overeager to only experience upward progress, but I also need to temper my glee with humility-- a great day doesn't make be any better than I was the day before.
I'm still practicing.