This is just me.

When I climb on a bike, I think of it as laborious as chopping wood. It's a chore.

However, if you get on some Kentucky rolling roads, you can fire down one hill and darn near coast all the way up the next roller.

I call this free wood.

So when I'm padding my climbing numbers by going up and down rollers, I think of it as getting free wood.

I'd use this expression, but no one would know what I was talking about, and someone would make a dirty joke about it.

BTW, I got no free wood today. I had to earn what few feet I climbed.