Stand up and get into a wide stance with your back straight and vertical and a dumbbell hanging between your legs in your hands. Your head should be up as if looking into the horizon. This is your starting position.
Squat down all the way until the dumbbell is just a few inches away from the floor. Focus on keeping your back as vertical as possible. Once down, push back up until you get back into the starting position but remember not to lock-out (straighten) your legs all the way! You should always keep tension in your legs for maximum movement efficiency.
Finally, repeat the entire movement for the desired or prescribed number of repetitions.
DO
DON'T
Perform this exercise in a smooth and fluid motion
Keep your back straight and as vertical as possible at all times
Don't extended your legs completely straight on the upward portion of the movement
SPECIAL NOTES & LEVEL of DIFFICULTY VARIATIONS
To increase the level of difficulty, slow down the movement or use a heavier dumbbell.