Comparing Effects of a 12-Week Aerobic Interval Training with and without Fennel on Metabolic Syndrome Indices and Estrogen Metabolites in Obese and Menopausal Women

Background and Objectives: Decreases in metabolism of estrogen and plasma levels of estrogen are associated with increased metabolic syndrome and cancer risk factors in postmenopausal women. The objective of this study was to investigate effects of a 12-week aerobic interval training with and without fennel consumption on metabolic syndrome indices and estrogen metabolites in obese and menopausal women.  Materials & Methods: In this semi-experimental study, 26 obese and menopausal females aged 50–60 years were randomly assigned to two major groups of training-placebo and training-supplement. Training was carried out at 45–65% heart rate reserve, three days per week for 12 weeks. Training-supplement group included 100 mg of the fennel supplementation. Samples were collected 48 h before and after the last sessions of exercise training. Metabolites of estrogen, including 2-hydroxyestrone and 16-α-hydroxyestrone, were assessed using enzyme-linked immunosorbent assay (ELISA). Data were analyzed using ANCOVA and SPSS Software v.18. Results: Body weight and body mass index (BMI) decreased in training-supplementation group in obese menopausal women, compared to training-placebo group (p < 0.05). No significant differences were seen in blood pressure, HDL and WHR. Furthermore, plasma levels of 16-α-hydroxyestrone significantly decreased while the ratio of 2-hydroxyestrone to 16-α-hydroxyestrone significantly increased with significant differences between the two groups (p < 0.05). Conclusion: Combination of aerobic interval training with fennel consumption may decrease body weight, BMI and 16-α-hydroxyestrone and increase 2-hydroxyestrone in obese menopausal women.