This form of cross-training brings some surprising benefits.

I know swimming isn’t for everyone, and many runners would rather sport seven bloody toe blisters than swim back-and-forth umpteen times. But through my always-foggy goggles, I’m seeing some upside beyond the conditioning benefits. Specifically:

Reminders about the importance of form: In the water, form can be just as much of a difference maker between speeding up or slowing down. Eyes down, elbows up, rotate torso, breathing rhythm. Sure, the body position is different between horizontal and vertical training, but swimming has nudged me to think more about little body changes that can help on the road.

Mental stamina: A couple weeks ago, I did a two-mile swim. When you poke through the water like I do, that distance takes a loooong time. That’s many, many minutes of looking down at a black line—no music, no scenery, nothing but your mind numbly counting wall touches. I feel like that has helped me hang on for longer during tough runs.

Hunger management: On the scale of knowing when I’m the hungriest, “after a swim” ranks pretty high. (Probably right after “all the freaking time.”) But during this stretch of training, I’ve consciously told myself I don’t need to eat right after swimming—and that’s helped me stay disciplined when my Pavlovian response is to justify a lot of calories just because I ran.

A Much-Needed Push: One day, I was sharing a lane with a guy who was swimming at a good clip. On my last 50-meter lap, I decided that I was going to try to stay with him when he passed me. When he came up on me with about 35 meters to go, I cranked as hard as I could. I stayed on his hip, and he eventually pulled away.

When you run alone as often as I do, you sometimes miss that extra push that comes from even artificial competition. The lap lane—if only for a few dozen meters—gave me that. And I will take that straight back to the track.

Ted Spiker usually does not have a sandwich after his sandwich workout, but if he did, he would like it to be corned beef with onions. You can follow him at @ProfSpiker on Twitter, Instagram, and Snapchat.