Date Presented 03/28/20
This study aims to compare the effects of dosage of sequential combination of cognitive and physical exercise training for the elderly with MCI. The high dosage (HD) group received a total of 36 training sessions and the low dosage (LD) group received a total of 12 training sessions. Both groups improved significantly in physical, cognition, and daily function. The LD group saw more benefits in general cognitive function. It is suggested that LD training was enough to improve functions in elderly with MCI.
Primary Author and Speaker: I-Ching Chuang
Additional Authors and Speakers: Ching-yi Wu
PURPOSE: Mild cognitive impairment (MCI) is a syndrome defined as an intermediate stage between cognitively intact and clinically diagnosed dementia. The progression rate from MCI to dementia ranges from 10 to 15% each year, resulting in increased family care and medical expenses. Effective and efficient interventions are essential for the community-based elderly with MCI. Sequential training, which is combining physical exercise and cognitive training sequentially, has positive influences on cognitive function in these people. However, it is yet not clear the appropriate dosage of the effective sequential training for elderly with MCI. Thus, this study aims to compare the intervention effects of high and low dosage of sequential training for the community-based elderly with MCI.
DESIGN: This study was a pre-post-test design and allocated participants from several community centers. The inclusion criteria in this study were: (1) MMSE≥17 and MoCA<26; (2) self- or informant-reported memory or cognitive complaints. Participants were randomly assigned to high dosage sequential combination of physical exercise training and cognitive training group (HD group, N=21) and low dosage combination of cognitive training and physical exercise (LD group, N=68).
METHODS: All participants received multicomponent exercise program that involves balance training, strength training, and aerobic exercise followed by cognitive training. The HD group received group training for 90-120 min/d, 2-3 d/wk, for a total of 36 training sessions. The LD group received group training for 90-120 min/d, 1 d/wk, for a total of 12 training sessions. The outcome measures involve cognitive functions, physical function and activities of daily living function (ADL). Cognitive tests included the Montreal Cognitive Assessment (MoCA), the verbal fluency subtest of Wechsler Memory Scale (WMS), and trail making test (TMT). Physical function was evaluated by Time up and go (TUG). The Lawton Instrumental Activities of Daily Living (IADL) was used to evaluate ADL. We used the analyses of covariance (ANCOVA) to investigate the effect of different training dosage on each outcome variable.
RESULTS: There were no significant differences in demographic characteristics between two groups. For the within-group comparison, both groups showed a significant improvement on cognitive, physical and daily function. ANCOVA analyses showed that the LD group improved more than the HD group at posttreatment on the MoCA (p = 0.004, η
2 = 0.093). There were no significant differences between groups on the verbal fluency (p = 0.104), TUG (p = 0.353), TMT (p = 0.185), and Lawton IADL (p = 0.994).
CONCLUSION: The results provided preliminary evidence that both groups improved significantly after training in the physical, cognition, and daily function. In addition, the LD group was more beneficial on general cognitive function assessed by MoCA. Moreover, the result revealed that the high training dosage was not better than the low training dosage, and thus, it is suggested that a total of 12 training sessions (low dosage) in 3 months were enough to improve physical, cognitive, and daily function in elderly with MCI. These outcomes confirm that the low training dosage is a feasible and effective alternative to general high training dosage administered at community centers. Future studies include a large sample of participants are needed to validate our findings.
References
Bamidis, P. D., Fissler, P., Papageorgiou, S. G., Zilidou, V., Konstantinidis, E. I., Billis, A. S., … Kolassa, I. T. (2015). Gains in cognition through combined cognitive and physical training: the role of training dosage and severity of neurocognitive disorder. Frontiers in aging neuroscience, 7, 152. doi:10.3389/fnagi.2015.00152
Tait, J. L., Duckham, R. L., Milte, C. M., Main, L. C., & Daly, R. M. (2017). Influence of Sequential vs. Simultaneous Dual-Task Exercise Training on Cognitive Function in Older Adults. Frontiers in aging neuroscience, 9, 368. doi:10.3389/fnagi.2017.00368
