Beneficial Effects of Water-Based Exercise Alone and in Combination with Cognitive Training on Cardiovascular Fitness and Arterial Stiffness in Older Adults with Mild Cognitive Impairment: A Randomized Controlled Trial.

Mild cognitive impairment (MCI) is the transitional stage between normal cognition and dementia and is associated with arterial stiffness, which may lead to cardiovascular disease. A water-based exercise (W) presents a low-impact activity for the joints and increases resistance compared to exercises performed in the air, which benefits older adults. However, little evidence has been found regarding the effect of W on promoting cognitive and physical performance in older individuals with MCI. Therefore, this study aimed to investigate and compare the post-training effects of W alone and in combination with cognitive training on cognitive function, cardiovascular fitness, and arterial stiffness in older adults with MCI. Forty-six adults with MCI, aged 65 years or older, were enrolled. Participants were divided into two groups: a W group and a water-based exercise combined with cognitive training (W-COG) group. Both groups performed an aerobic exercise program in water for 60 min per/day, 3 day/week, for 12 weeks. Participants in the W-COG group simultaneously performed aerobic exercise and cognitive training in water. Cognitive performance, cardiovascular fitness, and arterial stiffness were examined before and after the intervention. The results revealed improvements in cognitive performance and cardiovascular fitness in both the W and W-COG groups after 12 weeks of intervention. However, there were no significant differences in cognitive and cardiovascular fitness changes between the two groups. Neither the W nor the W-COG groups showed a decrease in brachial pulse wave velocity. Therefore, W interventions have the potential to enhance cognitive function, restore cognition, and improve cardiovascular fitness in older adults with MCI.