RELATIONSHIPS AMONG PHYSICAL ACTIVITY, LIMB BLOOD FLOW AND AUTONOMIC NEUROPATHY TESTS IN ADULTS WITH DIABETES

Abstract

Considerable evidence suggests that dysfunction in microcirculation is associated with diabetic neuropathy. In view of the fact that exercise is associated with increases in peripheral blood flow, it may be possible for exercise to be associated with decreased autonomic neuropathy. Thus, the purpose of this study was to examine the relationships among physical activity (PA), autonomic neuropathy tests (ANT), and limb blood flow (LBF) in adults with diabetes. It was hypothesized that adults with diabetes with greater PA would have lower scores on ANT and would have greater LBF than those with less PA. Twelve adults with diabetes, (7 women and 5 men); duration of diabetes = 12.0 ± 10.8 (SD) yrs; and a.m. glucose 153.3 ± 53 mg/dl; served as participants. Procedures were a seven-day exercise recall (Kcal/kg/week); ANT score derived from five cardiovascular autonomic function tests: 1) beat to beat variation to deep breathing, 2) orthostatic heart rate response, 3) orthostatic blood pressure response, 4) blood pressure response to handgrip, and 5) heart rate response to Valsalva maneuver; and LBF assessed by Laser Doppler Flowmetry at the flexor surface of the distal phalanx of the right great toe and the extensor surface of the right ankle. Pearson's Product Correlation identified a positive relationship between PA and toe blood flow (r = 0.693, p < 0.05) and a negative relationship between PA and ANT score (r = −0.639, p < 0.05), both independent of glucose control. However, no correlation was identified between LBF and ANT score. In conclusion, it may be possible for physical activity to increase peripheral blood flow and decrease neuropathy in adults with diabetes. Partially supported by Moore Instruments, Indiana University Department of Kinesiology and the Indiana University Adult Fitness Program.