I think that's a fairly common complaint for some people.
(I've seen the same question posted here quite a few times.)
Make sure you are well hydrated before and after your walk.
You can also do some "arm circles" or hand flexing while you walking which may help.
Generally it's nothing to be concerned with.....
SB doesn't really focus a whole lot on the amount of sodium in our diet, unless you are salt sensitive.
I'd also like to say "kudos" to you on the three mile walks!!
5' 6" , 130 , 49 yrs. Started SB 01-2005.
Sprinting (and cycling) enthusiastically along in Phase 3!
"I do not run to add days to my life-----I run to add life to my days."