I call this duckwalking - which has a double meaning - you have to duck under things while you walk and you look like a duck who is walking
These are very hard for me to do since I've had 3 back surgeries - we get to that point and I always say - look I can duck or I can walk, but I can't do both at the same time and someone (I never go out in the woods alone) will usually help me get past those both ways