The Effect of Exercise on Plasma Ghrelin in Obesity

Abstract

Background and Aim of the Work : Obesity is an important health problem worldwide. Many solutions have been proposed for this problem the most important of which is physical exercise. Exercise affects caloric expenditure signaling to ghrelin-producing cells in the stomach, thereby affecting appetite regulation. This study examined the effect of weight control programs and exercise on plasma acylated ghrelin concentration in obese subjects. Subjects and Methods : 120 obese persons were recruited and randomly assigned into two treatment groups: diet group& diet and exercise group. The first group received low caloric diet for 12 weeks, while the second group was treated with same diet and exercise program every other day for the same period. Complete clinical, laboratory investigations and ghrelin concentrations were assessed at the start and end of the study. Results : In the diet group, the body weight, the BMI, the WHR (Waist hip ratio) and waist circumference were significantly reduced. On the other hand appetite measures, the triglycerides, cholesterol, HDL and LDL serum levels did not change significantly. Acylated ghrelin was significantly increased. In the diet and exercise group, the body weight, the BMI, the WHR, waist circumference, the feeling of hunger, the desire to eat and prospective food consumption score were significantly decreased. Feeling of fullness score and Serum HDL were significantly increased. Serum triglycerides, serum cholesterol, serum LDL and acylated ghrelin were significantly reduced. Higher reduction of BMI was observed in individuals with lower serum levels of acylated ghrelin. Conclusion : Exercise training was associated with highly significant reduction of anthropometric measurements, plasma acylated ghrelin (which was associated with significant reduction of appetite measures), whereas diet intervention alone promoted opposite effects. More reduction in BMI was observed in individuals with lower plasma levels of ghrelin at the start of the study.