Oh yes! I hate it! I have forgotten to ask Dr. About because its never happening when I go. Sometimes it will happen a full day. I need to write this stuff down I have an appt on the 22nd of this month. I will ask. It's buggin me too.
I believe if you swing your arms down by your waist when you walk or run it you get swelling cause of excess blood there from the swinging. Try to keep hands and arms higher power walking style and see if there is a change.
I had the same problem when I started exercising a few weeks ago. But it has since disppeared. I think I fixed it with drinking lots of water and eating less sodium. Or maybe my body just got used to exercising?