Jundishapur Journal of Medical Sciences

Jundishapur Journal of Medical Sciences

The Effect of Two Types of Continuous and Interval Aerobic Exercise on Improving the Lipid Profile and Liver Enzyme Markers in Insulin-Resistant Prediabetic Rats

Document Type : Original Article

Authors
Sahar Zamani 1
Forouzan Fattahi Masrour 2
Maghsoud Peeri 3
1 PhD in Exercise Physiology, Department of Exercise Physiology, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
2 Assistant Professor of Exercise Physiology, Department of Exercise Physiology, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
3 Professor of Exercise Physiology, Department of Exercise Physiology, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
10.22118/jsmj.2026.565417.4107
Abstract
Background:
Prediabetes accompanied by insulin resistance is associated with metabolic disorders, including dyslipidemia and liver damage. The aim of this study was to compare the effects of two aerobic exercise protocols—continuous aerobic training and high-intensity interval training—on the lipid profile and liver enzymes in a fructose-induced prediabetic animal model.
Methods:
Thirty-two female Wistar rats were randomly divided into four groups: healthy control (C), diabetic control (D), diabetic + continuous exercise (D+CONT), and diabetic + interval exercise (D+INT). After inducing prediabetes with fructose, the exercise protocols were performed for 8 weeks, 5 sessions per week. At the end, serum levels of glucose, lipids (triglycerides, total cholesterol, LDL, HDL), liver enzymes (ALT, AST, ALP), HOMA-IR, and oxidative stress index were measured.
Results:
Induction of prediabetes led to a significant increase in glucose, severe dyslipidemia, and elevated liver enzymes and MDA (p < 0.001). Both exercise protocols resulted in a significant reduction in serum glucose (to levels similar to the control group), improvement in the lipid profile (decrease in triglycerides, cholesterol, and LDL; increase in HDL), and reduction in liver enzymes and MDA. However, no statistically significant differences were observed between the two exercise groups in any of the examined indicators (p > 0.05).
Conclusions:
Both continuous and interval exercise methods were equally effective in improving metabolic, lipid, and liver indices in the prediabetic animal model. This finding suggests that the choice between these two methods can be based on individual preferences, as their metabolic efficacy is equivalent.
Keywords
Continuous exercise
Interval exercise
Lipid profile
Liver enzymes
Prediabetes
Subjects
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Jundishapur Journal of Medical Sciences
Volume 25, Issue 3 - Serial Number 162
September and October 2026
Pages 199-207

  • Receive Date 10 December 2025
  • Revise Date 27 May 2026
  • Accept Date 31 May 2026