This Tabata circuit combines six rounds of wall balls and six rounds of wall sits. These moves get your heart rate up and work your entire body, with an emphasis on the glutes and legs. Required equipment: Medicine ball (6-14 lbs) and a sturdy open wall. Repeating this workout? The actual workout starts at 3:45 (3 minutes, 45 seconds into the video). Feel free to skip the intro if you don't need a review about wall balls and wall sits.