AUTHOR=Nhan Keegan , Todd Kendra R. , Jackson Garett S. , Van der Scheer Jan W. , Dix Gabriel U. , Martin Ginis Kathleen A. , Little Jonathan P. , Walsh Jeremy J. 

TITLE=Acute submaximal exercise does not impact aspects of cognition and BDNF in people with spinal cord injury: A pilot study

JOURNAL=Frontiers in Rehabilitation Sciences

VOLUME=3

YEAR=2022

URL=https://www.frontiersin.org/journals/rehabilitation-sciences/articles/10.3389/fresc.2022.983345

DOI=10.3389/fresc.2022.983345

ISSN=2673-6861

ABSTRACT=<sec><title>Objective</title><p>To investigate the effect of acute submaximal exercise, based on the spinal cord injury (SCI) Exercise Guidelines, on cognition and brain-derived neurotrophic factor (BDNF) in people with SCI.</p></sec><sec><title>Design</title><p>Eight adults (7 males) with traumatic SCI volunteered in this pre-registered pilot study. In randomized order, participants completed submaximal intensity arm cycling (60% of measured peak-power output at 55–60 rpm) for 30 min or time-matched quiet rest (control condition) on separate days. Blood-borne BDNF was measured in serum and plasma at pre-intervention, 0 min and 90 min post-intervention. Cognition was assessed using the Stroop Test and Task-Switching Test on an electronic tablet pre- and 10 min post-intervention.</p></sec><sec><title>Results</title><p>Submaximal exercise had no effect on plasma [F<sub>(2,12) </sub>= 1.09; <italic>P </italic>= 0.365; <italic>η</italic>² = 0.069] or serum BDNF [F<sub>(2,12) </sub>= 0.507; <italic>P </italic>= 0.614; <italic>η</italic>² = 0.024] at either 0 min or 90 min post-intervention. Similarly, there was no impact of exercise on either Stroop [F<sub>(1,7) </sub>= 2.05; <italic>P </italic>= 0.195; <italic>η</italic>² = 0.065] or Task-Switching performance [F<sub>(1,7) </sub>= 0.016; <italic>P </italic>= 0.903; <italic>η</italic>² &lt; 0.001] compared to the control condition. Interestingly, there was a positive correlation between years since injury and resting levels of both plasma (r = 0.831; <italic>P</italic> = 0.011) and serum BDNF (r = 0.799; <italic>P</italic> = 0.023). However, there was not relationship between years since injury and the BDNF response to exercise.</p></sec><sec><title>Conclusions</title><p>Acute guideline-based exercise did not increase BDNF or improve aspects of cognition in persons with SCI. This work establishes a foundation for continued investigations of exercise as a therapeutic approach to promoting brain health among persons with SCI.</p></sec>