There are many upper body exercises you can do along with lunges. It is an
especially good idea to include your isolation exercises for small muscle groups
along with walking lunges as it will allow you to get them out of the way,
giving you more time to work on adding more weight to your compound exercises.
In this case, if you perform military press or
heavy dumbbell shoulder press early in your legs and shoulders workout,
you can add walking lunge front raise later in an attempt to maximize your time
in the weight room. This in turn will give you more time to do cardio or recover
from exercise.