Immediate Effects of Arm Reaching Training in Standing on Postural Control Differ between Right and Left Stroke Individuals.

BACKGROUND:Arm reaching training in standing for several weeks affects the postural control of individuals recovering from cerebrovascular accident (CVA). Whether these effects differ with the side of the brain lesion are unknown. OBJECTIVES:To examine the immediate effects of a training session of arm reaching movements on the balance and trunk motion of individuals who suffered a right or left CVA. MATERIALS AND METHODS:Thirty-six adults divided into four groups (i.e., right CVA, left CVA, right control, and left control) performed 120 reaches in a standing position toward one of three target heights. Before and after the reaching trials, participants stood as quiet as possible on two force plates and had their postural sway, trunk motion, and body weight distribution assessed. RESULTS:CVA groups showed greater postural sway regardless of the brain lesion's side compared to the control groups. After the session of reaching movements, the left stroke group reduced the postural sway and trunk displacements. Larger ranges of weight-bearing asymmetry were more frequent after the training session, mainly for the right stroke group. CONCLUSIONS:A single session training of reaching movements affects mostly the postural control of left stroke survivors. More training sessions may be needed for individuals after right stroke to show balance improvements. The current findings support the hemispheric specialization for postural control and suggest that the training involving arm movements in standing can benefit the motor rehabilitation of stroke individuals.