I've been noticing that recently that I am experiencing less fidgitiness in my meditation sessions. I think mostly I've just gotten stronger, that the extra muscle is better able to support my spine, allowing me to keep my seat for longer periods of time without discomfort.
I've also been doing these insane leg stretches every morning which is definitely helping my legs. I haven't talked about them yet but I'll get around to it soon.
And with all the exercise healthy food my mind is certainly clearer.
I thought my zazen was pretty "good" before but now it's coming easier than it has for a long time, since I was in the Peace Corps (another time I was on a low calorie diet (not by choice) and pretty fit (also not by choice!).