Obesity Adds Constraint on Balance Control and Movement Performance

Abstract

We examined if a weight loss program improves the speed-accuracy tradeoff of goal-directed aiming movements of obese individuals. Ten obese subjects aimed at targets of different sizes from a seated and a standing posture. The kinematics of the aiming was recorded. All participants were evaluated before and after a weight loss program when weight reduction had stabilized. Before weight loss, movement times and duration of deceleration phases were longer when subjects were standing than when they were seated. These effects vanished after weight loss. Weight loss yielded an increased aiming speed when subjects aimed at targets from an upright posture and this effect was greater for the smaller target. This difference was not observed when seated. The results suggest that a more stable postural platform resulting from weight loss allows a better control of the upper-limb movement.