Effects of motor and cognitive dual-task performance in depressive elderly, healthy older adults, and healthy young individuals

Impairments in dual-task performance can be observed in healthy older adults when motor and cognitive assignments are applied simultaneously. According to the hypofrontality hypothesis, there may be a reduction in frontal cognitive function during exercise. Objective The aim of the present study was to compare the performance changes on cognitive tests of depressive elderly (n=10), healthy older adults (n=10), and healthy young individuals (n=10) during cycle ergometer exercise. Methods The groups were submitted to a working memory test, a short memory test and a semantic memory test, before and during a 20-minute cycle ergometer exercise at 80% of their age-predicted maximal heart rate. Results Significant differences (p=0.04) were observed in scores on the digit backward test during exercise when young individuals were compared to healthy older adults. This result indicates that young subjects, as expected, had better performance than elderly. No significant differences were found among the groups for the digit forward subtest (p=0.40) or the vocabulary test (p=0.69). Conclusion Data from this study showed that healthy older adults had impaired performance on higher cognitive tasks when these assignments were applied together with motor tasks.