There is substantial evidence showing that physical activity and specially structured exercise supports cognitive health. One of the known mechanisms that connect exercise and the brain is a protein called brain- derived neurotrophic factor (BDNF). BDNF is involved in the growth and repair of brain cells. Results from aerobic exercise studies have shown upregulation and increased circulating levels of BDNF. The effect of aerobic exercise on BDNF increases as exercise intensity increases. The impact of resistance exercise on BDNF is less clear so researchers from Murdoch University in Australia conducted a study to find out.
This study, published in the Journal of Science and Medicine in Sport compared the effect of two different resistance exercise workouts on BDNF levels. One group performed a strength- focused workout (5 reps x 5 sets with 3 minutes’ rest between sets). The other group performed a hypertrophy-focused workout (10 reps x 3 sets with 1 minute’s rest between sets). To measure BDNF levels, blood samples were collected before warmup, immediately after the workout, and then 30 minutes later.
Hypertrophy workouts produced a significant increase in BDNF levels while strength workouts did not.
Acute resistance exercise using a moderate rep range increases serum BDNF concentrations when performed at 100% of 10RM with 60 seconds of rest in between sets. Hypertrophy-type resistance exercise is likely to provide cognitive benefit due to increased BDNF expression.
The take-home message from this study is that bodybuilding, or at least the time training in the gym, is a healthy endeavor and should be maintained throughout your life not just to maintain physical strength but also to help maintain cognitive function as you age.