Combined exercise training improves specific domains of cognitive functions and metabolic markers in middle-aged and older adults with type 2 diabetes mellitus

Aim: To investigate the effects of 8-weeks of CT on specific domains of cognitive function, metabolic and cardiovascular parameters of subjects with Type 2 Diabetes Mellitus (T2DM). Methods: 31 sedentary T2DM adults and older divided into CT (3x/week, during 8-week, n = 16) or Control group (CONT, n = 15). Before and after the intervention, a cognitive task battery, blood samples, and functional tests were assessed. Results: CT improved inhibitory control (d = 0.89), working memory (d = 0.88), cognitive flexibility (d = 0.67) and attention/concentration (d = 0.64) in T2DM subjects. However, memory, verbal fluency, and processing speed (d < 0.1, p > 0.05 for all) were not changed. The CTinduced improvements on global cognitive z-score (r = -0.51; p < 0.001) were inversely correlated to cognitive screening scores. Moreover, CT improved functional performance (p < 0.05) and reduced insulin levels (p = 0.04). Although there was no statistical significance, there were a clinically relevant reduction of peripheral insulin sensitivity (d = 0.51, p = 0.09), resistin levels (d = 0.53, p = 0.08), diastolic (d = 0.63, p = 0.09) and mean blood pressure (d = 0.50, p = 0.09). Conversely, no changes were observed for glucose, fructosamine and blood lipids (d < 0.2 for all). Conclusion: CT partially reversed the negative effects of T2DM on specific cognitive domains possibly by amelioration of metabolic regulation. Moreover, lower cognitive scores may modulate the responsivity of cognitive function to CT. (C) 2021 Elsevier B.V. All rights reserved.