Thanks for the tip. While you are at it, check out the Swiss knot. Far easier to untie than a double knot with all of the same security. I've never had a shoe come untied since I started using it.
@@UltraTrailSteven Esentially, on the loop part of the knot, you run it through a second time. You can still untie it by pulling an end like a single knot, but it doesn't come untied.
