Neurotrophic growth factor response to lower body resistance training in older adults

Multimodal cognitive interventions (resistance training + cognitive training; RT + CT) may synergistically improve cognitive function in older adults. RT stimulates the release of neurotrophic growth factors (NGF) which orchestrate structural and functional brain plasticity in the aging brain, while CT increases regional cerebral blood flow. Timing the administration of CT following a bout of RT, when NGF levels are at their highest, may maximize the blood‐borne dose of NGF delivered to active brain tissue. We refer to this as the ‘anabolic window’. Currently, when and how much NGF levels in the blood increase following a bout of RT is poorly understood. The purpose of this work was to characterize the timing and magnitude of insulin like growth factor‐1 (IGF‐1) and brain derived neurotrophic factor (BDNF) levels in venous blood for 2 hours following an acute bout of RT. Methods 10 older adults (ages 60 – 77) performed 1 hour of lower‐body RT and rested for 2 hours post‐exercise. Blood was taken before and for 2 hours after RT at set time points. This procedure was repeated after 8‐weeks of regular RT. Results BDNF increased immediately post‐exercise then returned to resting levels before and after 8 weeks of RT. IGF‐1 levels did not change. Conclusions these data are the first to show an increase in BDNF immediately following RT in older adults. This may represent the anabolic window for performing CT. NSERC