The Bone Endocrine Function, Insulin Resistance Index, and Lipid Profile of Inactive Girls after 4 Weeks of High-Intensity Plyometric Training

Physical activity and exercise can affect the bones, and participate in glucose and fat metabolism by releasing osteokines such as under-carboxylated osteocalcin. Therefore, the aim of this study was to investigate the effect of 4 weeks of high-intensity plyometric training on serum levels of under-carboxylated osteocalcin, insulin resistance index, and lipid profile components in inactive girls.

This was a semi-experimental research with pretest-posttest design. 24 inactive girl students with mean age of 24.16 ± 1.53 years and mean body mass index (BMI) of 22.22 ± 1.01 kg/m2</sup> were randomly divided into two equal groups of Plyometric training and control. The exercise protocol was performed for 4 weeks (three session per week), while the control group did not have any regular physical activity. Blood samples were obtained before and after the intervention period for under-carboxylated osteocalcin, lipid profile, glucose, insulin, and insulin resistance measures. The data were analyzed using independent and dependent t-test (P < 0.050).

There was a significant decrease in blood glucose level (P = 0.035), insulin resistance index (P = 0.040), and some lipid profile parameters such as cholesterol (P = 0.040) and low-density lipoprotein (LDL) (P = 0.025) in the training group. Moreover, a significant decrease was seen in blood glucose serum level (P = 0.025) and insulin resistance index (P = 0.030), with no significant change in under-carboxylated osteocalcin and lipid profile components in the exercise group compared to the control.

A significant reduction was observed in blood glucose serum levels, insulin resistance index, and improvement of some lipid profile components in inactive girls, which appeared to be independent of changes in bone endocrine function index (under-carboxylated osteocalcin).