Background: Phlebodium Decumanum is a type of fern that could have an immune or stress response modulating action.
Aim: To evaluate if the consumption of a preparation obtained from Phlebodium Decumanum, modifies the changes induced by exercise in plasma levels of testosterone and cortisol.
Material and methods: Fourteen male subjects aged 22 +/- 2 years were randomized to consume Phlebodium Decumanum and 10 subjects, aged 23 +/- 1 years were ascribed to consume a placebo. Both groups performed a standard exercise program, three times a week during one month. Plasma free testosterone and cortisol levels were measured before and 48 hours after the last session of the exercise program.
Results: Cortisol levels increased significantly from 18.9 +/- 6.8 to 26.2 +/- 5.9 fig/dl, in the control group. In the group consuming the study product, no changes were detected (20.0 +/-4.6 and 20.9 +/- 5.9) fig/dl before and after the exercise program, respectively). Plasma free testosterone decreased significantly in both groups from 36.1 +/- 11.04 to 20.7 +/-4.3 pg/ml in the control group and from 33.7 +/- 10.0 pg/ml to 18.6 +/- 4.9 pg/ml in study group.
Conclusions: The cortisol levels increased significantly in the control group but not in the study group. Therefore we can suggest that consumption of Phlebodium Decumanum would be able to modulate the response of this hormone to physical stress.