I ran a 7:49 mile in the fourth grade. They thought I cheated and skipped a lap. I didn’t, but I too was surprised by my relative speed. I was one of those types who did the bent arm hang instead of pull ups. I thought I was not athletic and couldn’t achieve much physically, so generally, I didn’t. Until I did.

Our expectations for ourselves can be far more limiting than our bodies and I have had to learn this lesson throughout my life.

I am currently training for my first marathon. It is humbling, exciting, and occasionally painful. Mostly it is a matter of putting one foot in front of the other. In this process I have learned a lot. I must prepare. I must be willing to challenge what I think my body cannot handle. I must confront fears and jettison habits that have carried me through decades of 5Ks and dedicated running that was good, but not marathon-level.

For example: Eating while I run will not make me throw up, nor does it obliterate the point of a workout — I have to do it to survive. Or, pushing through pain is not heroic or tough; if I don’t take breaks when my body tells me to, I won’t be able to run my race. I knew I had gone pro when my period started while I was on a busy street, and I just kept going.

More than anything, marathon training has taught me that I can mostly do what I say I’m going to do if I focus and commit. It is also training me to better recognize the boundaries of what focus and commitment can achieve. I can’t and won’t become everything I’ve dreamed of, including some things I had thought more achievable than running a marathon. And yet, remarkably, I’m still going.