Effects of Acute Aerobic Exercise on Cognitive Function in Individuals with Down Syndrome

Abstract

Individuals with Down syndrome (DS) commonly exhibit a mild to moderate level of cognitive impairment, which further affects quality of life in this population. Regular aerobic exercise has been shown to improve cognitive function among individuals with and without DS. However, if an acute bout of moderate intensity aerobic exercise has cognitive benefit in individuals with DS has yet to be explored. PURPOSE: To investigate the effect of an acute bout of aerobic exercise on cognitive function in individuals with and without DS. METHODS: Forty volunteers with and without DS (DS=20, 25 yrs; Control=20, 25 yrs) participated in this study. VO2peak was obtained via indirect calorimetry by an individualized maximal exercise treadmill protocol. Participants exercised at 60% of maximal capacity for 20 min on a separate day. Cognitive function tests (task completion time and accuracy of task completion, A Quick Test for Cognitive Speed, AQT) were measured before, immediately after, and 30 min after the submaximal walking bout. Individuals without DS performed an additional cognitive function test, the Flanker test, to avoid the known ceiling effect of the AQT. RESULTS: Individuals with DS exhibited impaired cognitive function compared to individuals without DS with slower task completion time and higher error rate. (p < 0.05 for both). AQT components, task completion time and error rate, were not altered after 20 min of treadmill exercise in either group. However, improved reaction time and error rate on the Flanker test (immediate; 30 min post), suggest exercise positively benefited cognitive function among those without DS. (p < 0.05). CONCLUSIONS: Our results indicate that individuals with DS may need a higher intensity or longer exercise time for cognitive improvement. In addition, in-depth cognitive function testing may be more sensitive in detecting changes with exercise in individuals with DS.