Static balance is affected following an exercise task in chronic obstructive pulmonary disease

PURPOSE: To investigate balance following a submaximal exercise task (6-minute walk test [6MWT]) in patients with chronic obstructive pulmonary disease (COPD). METHODS: A consecutive sample of 19 patients with COPD from an institutional pulmonary rehabilitation program served as participants. The following measures were recorded before and following a 6MWT: (1) timed-up and go (TUG) test, (2) step-up test, and (3) quiet standing for 30 seconds with eyes open and closed in a narrow and semi-tandem stance. Displacement of the body at the level of the waist was recorded using a swaymeter. Data were analyzed using a linear mixed model. RESULTS: In the semi-tandem stance with eyes closed post-6MWT, increases in total sway (165.9 mm vs 240.0 mm, P = .043) and mediolateral sway (45.8 mm vs 66.6 mm, P = .011) were found in comparison with pre-6MWT measures. The exercise task did not affect the TUG test performance (8.3 seconds vs 9.0 seconds, P = .213), number of steps completed during the step-up test (10 vs 10, P = .233), or sway during the semi-tandem stance with eyes open; narrow base, eyes open or closed (P > .05). Conclusions: A submaximal exercise task in patients with COPD affects balance during static standing tasks in the absence of visual input. This may have implications for functional performance following exercise in patients with chronic respiratory disease. (C) 2008 Lippincott Williams & Wilkins, Inc