First of all, how can you not love an exercise featuring the words "dirty dog" in its name? And secondly, it truly is a great butt-toning move. Since this is a standing variation, rather then being on all fours [1], you are going to work your core a lot more too. Bonus!

• Stand with your feet hip-width apart and your hands on your hips.
• With your core engaged and a solid standing right leg, lift your left leg out to the side, keeping the left knee bent. Squeeze your waist and hip. Do not lean to the right as you lift the leg — really focus the work in your waist and hip.
• Lower the left leg down, barely touching the ground with your left toes, then lift that leg up and repeat for a total of 15 reps.
• Keep the leg lifted on the last rep, and make 15 small pulses in a one-inch range to concentrate the work in your glutes and obliques. Then switch sides. Do at least two sets on each side.