Still Moving.....
Hmmm, my DH gets a cramp in his calf once in a while, and that sucks - he just has to wait it out. I recall that my calves barked for a long time when I first started my walk/jog thing 21 years ago. I had to work thru it, stretching did not help. I did my walks on an empty stomach, first thing in the am, but somehow it never occurred to me to eat something first. Who knows that may have helped me too! I don't think it was a potassium drop - that usually happens after a biggo workout. Potassium comes from veggies, fruits, have you been doing good on eating that stuff? I'm with Al, may be a stretch thing before you go is worth a try. It cannot hurt to eat a light snack or drink some low sugar gatorade - just a little bit, not one of those bog chugs of it.