Train in multiple planes with “around the clock” lunges, so you can handle uneven terrain.
The exercise Lunge forward with your right foot into the 12 o’clock position. Then lunge to 1:00 (your torso and left leg still face noon). Travel around the face until 6:00 (a backward lunge). Switch to your left foot, and go clockwise from 6 to noon. Do four sets; weighted pack optional.