Investigating the role of intensity of exercise training on plasma apelin concentrations and insulin resistance in elderly patients with type 2 diabetes

The purpose of this study was to compare the effect of high intensity interval training (HIIT) and moderate continuous training on plasma apelin concentrations and insulin resistance in elderly patients with type 2 diabetes. 39 elderly males and females were randomly divided into three groups: high intensity interval training (HIGH), moderate continuous training (CONT) and control (CTL).
This research was a clinical trial; it was informative and quantitative one in collecting information. Training interventions were performed three times per week and for 10 weeks on a bicycle ergometer. The high intensity interval training included 6 intervals and each interval included 4 minutes with 85-90% HRmax and 3 minutes with 45-50% HRmax. The moderate-continuous training included 42 minutes cycling with 70% HRmax. 48 hours after the last training session, blood sampling was performed and plasma apelin levels, lipid profile, glucose, glycosylated hemoglobin, and insulin plasma levels were measured.
ANOVA test and Tukey post hoc test showed a significant decrease in insulin resistance in the two groups of training compared to the control group (P = 0.019). The plasma apelin levels in the high intensity interval training group was significantly lower than the control group (P = 0.022). Cardio respiratory fitness (VO2peak) was significantly increased in the training groups compared to the control group (P = 0.008). After a 10-week exercise, HDL-levels increased significantly in exercise groups (P = 0.022) and decreased significantly compared to the plasma levels of LDL (P = 0.046). However, there was no significant difference between the training groups. All the values were expressed as mean± SEM and P Possibly in elderly patient with type 2 diabetes high intensity interval training have a greater effect on the improvement and regulation of the secretion of apelin and other glycemic indices compared to continuous training protocols.