The effect of an acute bout of high intensity intermittent exercise on neural growth factors in young adults: Sex differences

Abstract
The neurophysiological response to exercise on cognition is modulated through chemical pathways which involve several neurotrophic factors and the sex of the individual determines this effect. We examined sex differences in the concentration of neural growth factors (NGF); brain derived neurotrophic factor (BDNF), vascular endothelial growth factor (VEGF) and insulin like growth factor-I (IGF- I) in response to acute high intensity intermittent exercise (HIIE). We also evaluated the relationship of NGF with gonadal hormones before and after the HIIE session. Forty healthy young adults (22 males and 18 females) performed HIIE (4 bouts of 4 minutes at 90–95% HR max with 3min active recovery at 70% HRmax). Venous blood was drawn before and immediately after the exercise session and was analyzed for the concentration of serum BDNF, VEGF, IGF-I, cortisol, estradiol, luteinizing hormone (LH), follicle stimulating hormone (FSH) and testosterone, using ELISA method. A significant sex difference (p<0.05) was observed for BDNF concentration in response to HIIE and a significant increase was found in males but not in females. A significant (p<0.005) positive correlation of BDNF with FSH and LH and a significant (p<0.05) negative correlation of BDNF and VEGF with testosterone were found. Other NGFs (VEGF and IGF-I) did not show sex differences in response to HIIE. In conclusion, a single session of HIIE increases the serum concentration of BDNF in males and IGF-I in females and the response of NGF is different in males and females.