Often clients tell me their backs can feel tight, stiff, or achy after walking more than usual, and they want to know what to do about it! My (not so) secret to easing the backache that comes with long walks is the 10 second squat sit.
The squat sit unloads your spine and gives the glute and back muscles a gentle stretch. Upon standing, your glute and core muscles concentrically contract, readying them for another walk about.
And think about it: If you were a hunter/gatherer, you'd probably drop down into a squat once or twice a day when nature called. Now it's NOT always good to look to the past to make health choices for today. (please keep your vaccines up to date!) But our evolutionary history of walking proves to still be a healthful choice for modern humans today, and I believe the 10 second squat sit is another human movement best done daily, even though there are plenty of chairs around.
If you have tight ankles and hips, you might need to hold on to something in front of you. Or, go for the "I'm tying my shoe" squat with one heel down at a time. Those with uneven knee flexion ranges may fair better with a few cat/cows while on all fours.