Pacing?

[Transylvania]

Last night my juvie A. minatrix, for some reason, felt like pacing around its enclosure for a few hours. It confused me, because it hardly ever leaves its webs, let alone explores its entire cage from top to bottom over and over and over again. I couldn't come up with a good explanation for it. It has lived in this enclosure for a year. The humidity was fine and it had just been fed a big fat cricket a few days ago. It didn't seem distressed in any way - it just looked like it was out for a casual midnight stroll.
I'm sure this behavior is common, but is there a better explanation for it, other than it "just felt like exploring"?

 

[NikiP]

How large is it & has it molted (possibly matured?) recently?

My A. anax is a busy bee, always moving or digging. Not a MM. I just let it be.

 

[Chris_Skeleton]

I have an A. metallica that will pace around it's enclosure quite frequently.

 

[Transylvania]

It's 2" and its last molt was a few months ago.