Improved cognitive performance following aerobic exercise training in people with traumatic brain injury

Objective: To examine cognitive function in individuals with traumatic brain injury (TBI) prior to and after participation in an aerobic exercise training program.

Design: Pre-post intervention study.

Setting: Medical research center.

Participants: Volunteer sample of individuals (N=7) (age, 33.3±7.9y) with chronic nonpenetrating TBI (injury severity: 3=mild, 4=moderate; time since most current injury: 4.0±5.5y) who were ambulatory.

Intervention: Twelve weeks of supervised vigorous aerobic exercise training performed 3 times a week for 30 minutes on a treadmill.

Main outcome measures: Cognitive function was assessed using the Trail Making Test Part A (TMT-A), Trail Making Test Part B (TMT-B), and Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Sleep quality and depression were measured with the Pittsburgh Sleep Quality Index (PSQI) and Beck Depression Inventory, version 2 (BDI-II). Indices of cardiorespiratory fitness were used to examine the relation between improvements in cognitive function and cardiorespiratory fitness.

Results: After training, improvements in cognitive function were observed with greater scores on the TMT-A (10.3±6.8; P=.007), TMT-B (9.6±7.0; P=.011), and RBANS total scale (13.3±9.3; P=.009). No changes were observed in measures of the PSQI and BDI-II. The magnitude of cognitive improvements was also strongly related to the gains in cardiorespiratory fitness.

Conclusions: These findings suggest that vigorous aerobic exercise training may improve specific aspects of cognitive function in individuals with TBI and cardiorespiratory fitness gains may be a determinant of these improvements.