Impact of Strength Training Intensity on Brain-derived Neurotrophic Factor

Area of Science:

• Exercise Physiology
• Neuroscience
• Biochemistry

Background:

• Brain-derived neurotrophic factor (BDNF) plays a crucial role in neuronal plasticity, learning, and memory.
• Exercise is a known modulator of BDNF levels, but the specific effects of varying strength-training intensities require further elucidation.

Purpose of the Study:

• To investigate the acute effects of different strength-training intensities on plasma BDNF levels in trained men.
• To compare the physiological responses, including lactate and BDNF changes, between 60% and 80% of one-repetition maximum (1RM) strength training.

Main Methods:

• A randomized crossover design was used with 14 trained male participants.
• Participants completed strength-training protocols (bench press, leg press, lat pull-down) at 60% and 80% of 1RM to failure, with 2-minute rest intervals.
• Blood samples were collected pre-exercise, immediately post-exercise, and one hour post-exercise.

Main Results:

• Strength training at 60% 1RM significantly increased plasma lactate but did not alter plasma BDNF levels.
• Strength training at 80% 1RM significantly increased plasma lactate and elevated plasma BDNF levels one hour post-exercise (461 to 1730 pg/ml, p=0.035).

Conclusions:

• A single session of high-intensity strength training (80% 1RM) is effective in increasing circulating BDNF levels.
• Intensity appears to be a critical factor in modulating the exercise-induced BDNF response during resistance training.