Effects of supplementation with virgin olive oil on hormonal status in half-marathon trained and untrained runners

Abstract

Several studies have investigated the effects of exercise on hormonal status. Several studies have reported that exercise induce alterations in hormone concentrations. This study focuses on the effects associated to the intake of virgin olive oil, rich in monounsaturated fatty acids (MUFA) on hormonal status in half-marathon athletes. The contents of tocopherols, phenolic compounds, Pigment, flavonoids, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical test and activity of the oil on hydrogen peroxide were determined. The consequence of the consumption of virgin olive oil on hormonal status was studied in healthy male athletes of ages between 19–22 years. The participants were separated into three groups of ten subjects each and reserved under distinct regimes for 10 weeks as follows: Group 1 untrained runners receiving 20 ml of olive oil, Group 2 half-marathon runner performing training routines, 5 days a week while receiving 20 ml of olive oil, Group 3 half-marathon runners performing training routines, 5 days a week unsupplemented with virgin olive oil. Blood samples were taken: one day before endurance training programme, after a 10- week endurance training programme, at the end of the training period, two days before the half-marathon race, and 24 hours after the half-marathon race. Plasma was analyzed for testosterone (T), luteinizing hormone (LH), Follicle Stimulating Hormone (FSH), cortisol (C) and insulin. The results of this study showed that virgin olive oil of Blanquette variety is characterized by high content of tocopherols, phenolic compounds (25.2 ± 0.07 mg/Kg, 485, 46 ± 1.35 mg/Kg), pigments with 79.34.± 0.92 ppm of Total carotenoids, and a high percentage inhibition of the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical and a percentage of hydrogen peroxide (H2O2) inhibition was observed (76.03 ± 0.43% and 86.45±0. 28%, respectively). The consumption of this oil was associated with statistically significant increase of Testosterone in supplemented groups compared with runner of non-supplemented group and sedentary controls. Luteinizing hormone (LH) concentration decreased in runners not supplemented with virgin olive oil compared to group 2 runners and sedentary controls. After a 10-week running training program (before half-marathon race) and immediately after a half-marathon race, cortisol only significantly increased (p<0.001) in runners of group 3; it then demonstrated a tendency toward declining 24 hours after a marathon race. This study found that virgin olive oil supplementation can improve hormonal status in half-marathon athletes. Key words: olive oil, monounsaturated fatty acid, tocopherols, exercise, half-marathon