Strength training does not influence serum brain-derived neurotrophic factor

The purpose of the study was to examine the acute effect of a strength training session on brain-derived neurotrophic factor and insulin-like growth factor 1. Furthermore, the influence of a 10-week strength training program on brain-derived neurotrophic factor (BDNF) and insulin-like growth factor-1 (IGF-1) resting levels and memory performance was studied. Fifteen untrained subjects followed a strength training program for 10 weeks. Eight control subjects remained physically inactive. To study the influence of an acute strength training session, blood samples were taken before and after the sixth and 30th sessions. Training effects were evaluated by taking blood samples at rest before and following the training program. Short- and mid-term memories were assessed using the digit span and a recall of images test. BDNF, IGF-1 and its binding protein (IGFBP-3) were measured in serum samples. Data were analyzed (p < 0.05) using a mixed design ANOVA model, Duncan's multiple range post hoc tests, and Pearson's correlation. A single strength training session did not influence BDNF and IGF-1 concentrations. No effect of the strength training period on BDNF, IGF-1, and IGFBP-3 was found. No correlation was found between peripheral BDNF and IGF-1. Short-term memory improved in both the experimental and control groups, but no difference between groups was present. Mid-term memory did not improve following the 10 weeks of training. A period of strength training in sedentary subjects does not significantly change the growth factors or memory function compared to a control group. Also, BDNF and IGF-1 are not acutely influenced by a training session. Further research should focus on the beneficial role of physical exercise in neurodegenerative diseases.