The Effect of 8 Weeks Low Carbohydrate Diet and Cross-Fit Training on Ghrelin, Insulin, and Appetite Levels in Active Woman

Document Type : Original Article (s)


1 Department of Sports Physiology, School of Sports Sciences, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran

2 Associate Professor, Department of Sports Physiology, School of Sports Sciences, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran

3 Associate Professor, Department of Physical Education and Sport Science, School of Sports Sciences, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran


Background: Human appetite is controlled by a complex matrix. The aim of this study was to determine the effect of low carb diet and cross-fit training on the levels of ghrelin, insulin, and appetite.Methods: In this semi-experimental study, 83 healthy women with an average age of 32.5 ± 7.7 years, weight of 60.5 ± 5.5 kg and body mass index of 22.7 ± 1.7 kg/m2 were selected using targeted sampling method, and randomly divided to 4 groups of low carbohydrate diet, cross-fit training, combination, and control. Training groups followed 3 sessions each week for 8 weeks, and diet groups followed a low-carb diet with 40 percent carbohydrate, 40 percent fat, and 20 percent protein for eight weeks. Ghrelin and insulin concentrations were measured after 12 hours of fasting at the baseline position and 48 hours after the last training session. Data were analyzed based on different groups.Findings: The amount of ghrelin in the diet group (P = 0.001) and the combined group (P = 0.008) significantly reduced, and in exercise and control groups was unchanged. Appetite rate decreased significantly in the two groups of diet (P = 0.003) and combination (P = 0.010), significantly increased in the exercise group (P = 0.040) and did not differ in the control group. Insulin levels did not change significantly in any of the groups.Conclusion: It can be concluded that a low carb diet reduces appetite and ghrelin concentration. More, the combined effect of exercise with diet is more effective than exercise alone. On the other hand, people without dietary restrictions tend to receive food compensation after intense strength training.


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