Electrical muscle stimulation in young adults: effect of muscle volume on brain-derived neurotrophic factor levels.

Abstract

Electrical muscle stimulation (EMS) is known to be effective at stimulating brain-derived neurotrophic factor (BDNF) levels, but the relationship between the volume of muscle stimulated and BDNF levels is not clear. The purpose of this study was to quantify BDNF as a function of muscle volume stimulated in young adults. Twelve young adults (male, n = 9, age = 27.3 ± 5.5years) were enrolled in this study. Participants completed three testing conditions in randomized order: 23min of maximum tolerated bilateral stimulation of (1) the quadriceps muscle or (2) the musculature of the entire lower limbs and (3) control testing and retesting after 23min without an intervention. Blood samples were collected before, immediately after, 20min after, and 40min after the intervention when EMS was applied to the thighs or the entire lower limb conditions. Serum obtained from blood collection was used for BDNF analysis. The delta value of BDNF for the test and retest in the control condition was - 42.1 ± 73.8pg/mL, and there was no significant difference between the test and retest BDNF. Compared to stimulation of the quadriceps muscle, stimulation of the entire lower limbs produced significantly higher BDNF at 20min post-treatment than those at pre-treatment or 40min post-treatment, and BDNF was also significantly higher immediately post-treatment than those at pre-treatment. Only stimulation of the quadriceps muscle did not induce a significant change between pre- and post-treatment. Our findings suggest that the volume of muscle stimulation is important for increased BDNF.