Background.
Paired exercise and cognitive training have the potential to enhance
cognition by “priming” the brain and upregulating neurotrophins.
Methods.
Two-site randomized controlled trial. Fifty-two patients >6 months
poststroke with concerns about cognitive impairment trained 50 to 70
minutes, 3× week for 10 weeks with 12-week follow-up. Participants were
randomized to 1 of 2 physical interventions: Aerobic (>60% VO
2peak
using <10% body weight–supported treadmill) or Activity (range of
movement and functional tasks). Exercise was paired with 1 of 2
cognitive interventions (computerized dual working memory training [COG]
or control computer games [Games]). The primary outcome for the 4
groups (Aerobic + COG, Aerobic + Games, Activity + COG, and Activity +
Games) was fluid intelligence measured using
Raven’s Progressive Matrices Test administered at baseline, posttraining, and 3-month
follow-up. Serum neurotrophins collected at one site (N = 30) included
brain-derived neurotrophic factor (BDNF) at rest (BDNF
resting) and after a graded exercise test (BDNF
response) and insulin-like growth factor–1 at the same timepoints (IGF-1
rest, IGF-1
response).
Results.
At follow-up, fluid intelligence scores significantly improved compared
to baseline in the Aerobic + COG and Activity + COG groups; however,
only the Aerobic + COG group was significantly different (+47.8%) from
control (Activity + Games −8.5%). Greater IGF-1
response at baseline predicted 40% of the variance in cognitive improvement. There was no effect of the interventions on BDNF
resting or BDNF
response; nor was BDNF predictive of the outcome.
Conclusions.
Aerobic exercise combined with cognitive training improved fluid
intelligence by almost 50% in patients >6 months poststroke.
Participants with more robust improvements in cognition were able to
upregulate higher levels of serum IGF-1 suggesting that this
neurotrophin may be involved in behaviorally induced plasticity.
No comments:
Post a Comment