Activity Analysis - Daily Cup of Coffee

Everyday on my way to school I drink a cup of coffee. When I get my cup of coffee out of my cup holder my arm begins in an extended position at the elbow, and it moves into flexion at the elbow as I bring the cup of coffee towards my mouth to take a drink. This extension and flexion at the elbow occurs in the sagittal plane about a frontal axis. The osteokinematics of the elbow during this activity are extension to flexion in an open kinematic chain; while the arthrokinematics can be described as the moving ulnar concave segment rolls and glides anteriorly on the convex humerus. The prime mover for elbow flexion is the biceps brachii, which performs a concentric contraction when bringing my coffee cup towards my mouth to take a drink.