The Effect of a Square-Stepping Exercise Intervention on Heart Rate Variability in Older Individuals with Type 2 Diabetes and Subjective Cognitive Complaints
Aging is associated with increased onset of diseases such as type 2 diabetes (T2D) and cognitive impairment. Heart rate variability (HRV), a measure of autonomic function, is reduced in T2D and may have the potential to indicate cognitive decline in this population. Square-stepping exercise (SSE) is a novel cognitive exercise recently implemented in cognitive research, which may have the potential to improve global cognitive function in T2D individuals. Participants with T2D (N=25, aged ≥ 50y) and self-reported cognitive complaints were randomized into either an SSE intervention or a wait-list (WL) control group for 24-weeks. HRV parameters (time and frequency domain) and GCF domains were assessed at baseline and 24-weeks. No significant differences were found in HRV parameters between groups at baseline and 24-weeks. However, heart rate was significantly reduced from baseline to 24-weeks in the SSE group, p = 0.046. Additionally, low and high frequency power were significantly decreased from baseline to 24-weeks in the WL group, p = 0.05 and p = 0.043 respectively. This study elucidates the impact of cognitive exercise training on HRV, however, it is inconclusive as to why a shift towards vagal modulation was observed in both the SSE and WL groups
