Cognitive function affects trainability for physical performance in exercise intervention among older adults with mild cognitive impairment

Kazuki Uemura,^1,3 Hiroyuki Shimada,¹ Hyuma Makizako,^1,3 Takehiko Doi,¹ Daisuke Yoshida,¹ Kota Tsutsumimoto,¹ Yuya Anan,¹ Takao Suzuki<sup>2

1</sup>Section for Health Promotion, Department for Research and Development to Support Independent Life of Elderly, Center for Gerontology and Social Science, National Center for Geriatrics and Gerontology, ²Research Institute, National Center for Geriatrics and Gerontology, Aichi, ³Japan Society for the Promotion of Science, Tokyo, Japan

Background: Although much evidence supports the hypothesis that cognitive function and physical function are interrelated, it is unclear whether cognitive decline with mild cognitive impairment influences trainability of physical performance in exercise intervention. The purpose of this study was to examine the association between cognitive function at baseline and change in physical performance after exercise intervention in older adults with mild cognitive impairment.
Methods: Forty-four older adults diagnosed with mild cognitive impairment based on the Peterson criteria (mean age 74.8 years) consented to and completed a 6-month twice weekly exercise intervention. The Timed Up and Go (TUG) test was used as a measure of physical performance. The Mini-Mental State Examination (MMSE), Trail Making Test Part B, Geriatric Depression Scale, baseline muscle strength of knee extension, and attendance rate of intervention, were measured as factors for predicting trainability.
Results: In the correlation analysis, the change in TUG showed modest correlations with attendance rate in the exercise program (r = -0.354, P = 0.027) and MMSE at baseline 
(r = -0.321, P = 0.034). A multiple regression analysis revealed that change in TUG was independently associated with attendance rate (ß = -0.322, P = 0.026) and MMSE score
(ß = -0.295, P = 0.041), controlling for age and gender.
Conclusion: General cognitive function was associated with improvements in physical performance after exercise intervention in subjects with mild cognitive impairment. Further research is needed to examine the effects of exercise programs designed to address cognitive obstacles in older adults with mild cognitive impairment.

Keywords: exercise, mobility, rehabilitation, Timed Up and Go test