How symmetrical is your body from left to right? You might assume both sides match perfectly. Small differences exist in nearly everyone. You measure 10 body parts on each side for five athletes and five non-athletes. These include: - all five fingers - the wrist and foot - the ear and forearm - the leg from knee to foot Athletes average 78% symmetry across all measurements. Non-athletes average 70%. The gap suggests a link between athletic ability and balanced body proportions.