Stand with your torso upright holding two dumbbells in your hands by your sides. T
Step forward with your right leg around 2 feet or so from the foot being left stationary behind and lower your upper body down, while keeping the torso upright and maintaining balance. Make sure that you keep your front shin perpendicular to the ground.
Using mainly the heel of your foot, push up and go back to the starting position.
Repeat the movement for the recommended amount of repetitions and then perform with the left leg.
Variations: There are several ways to perform the exercise.
One way is to alternate each leg. For instance do one repetition with the right, then the left, then the right and so on.
The other way is to do what I call a static lunge where your starting position is with one of your feet already forward. In this case, you just go up and down from that starting position until you are done with the recommended amount of repetitions. Then you switch legs and do the same.
A more challenging version is the walking lunges where you walk across the room. For walking lunges the leg being left back has to be brought forward after the lunging action has happened in order to continue moving ahead.
Lunges can be performed with dumbbells as described above or with a barbell on the back, though the barbell variety is better suited for the advanced athletes who have mastered the exercise and no longer have balance issues.