About us Latest Blogs Sport Aberdeen Alphabet Workout - E is for Elbow to Knee Plank E is for "Elbow to knee plank" as we reach day five of the Sport Aberdeen Alphabet Workout. Here is how to work on the perfect plank: Begin in plank position. Maintaining a tight core and flat back, bring your left knee to your left elbow. Pause and slowly return each to the starting point. Repeat with the other side and keep alternating Check back tomorrow for the letter F.