BDNF Responses in Healthy Older Persons to 35 Minutes of Physical Exercise, Cognitive Training, and Mindfulness: Associations with Working Memory Function

Abstract

Brain-derived neurotrophic factor (BDNF) has a central role in brain plasticity by mediating changes in cortical thickness and synaptic density in response to physical activity and environmental enrichment. Previous studies suggest that physical exercise can augment BDNF levels, both in serum and the brain, but no other study has examined how different types of activities compare with physical exercise in their ability to affect BDNF levels. By using a balanced cross over experimental design, we exposed nineteen healthy older adults to 35-minute sessions of physical exercise, cognitive training, and mindfulness practice, and compared the resulting changes in mature BDNF levels between the three activities. We show that a single bout of physical exercise has significantly larger impact on serum BDNF levels than either cognitive training or mindfulness practice in the same persons. This is the first study on immediate BDNF effects of physical activity in older healthy humans and also the first study to demonstrate an association between serum BDNF responsivity to acute physical exercise and working memory function. We conclude that the BDNF increase we found after physical exercise more probably has a peripheral than a central origin, but that the association between post-intervention BDNF levels and cognitive function could have implications for BDNF responsivity in serum as a potential marker of cognitive health.

Keywords: Aging; brain-derived neurotrophic factor; cognitive function; cognitive training; crossover design; exercise; geriatrics; intervention study; mindfulness; neuroplasticity.

Fig. 1

BDNF level changes from baseline at 0, 20, and 60 minutes after each intervention. Bars represent the difference in ng/ml serum between baseline and each post-intervention time point.

Fig. 2

BDNF response to physical exercise for each participant. Each bar depicts the change in BDNF level between the average post-intervention BDNF level (across the three time points) in relation to the baseline (pre-session) level for each participant in the physical exercise condition.

Fig. 3

BDNF response to cognitive training for each participant. Each bar depicts the change in BDNF level between the average post-intervention BDNF level (across the three time points) in relation to the baseline (pre-session) level for each participant in the cognitive training condition.

Fig. 4

BDNF response to mindfulness practice for each participant. Each bar depicts the change in BDNF level between the average post-intervention BDNF level (across the three time points) in relation to the baseline (pre-session) level for each participant in the mindfulness condition.