Use the Back button in your browser to see the other results of your search or to select another record.

Detailed Search Results

Exercise intensity affects acute neurotrophic and neurophysiological responses poststroke [with consumer summary]
Boyne P, Meyrose C, Westover J, Whitesel D, Hatter K, Reisman DS, Cunningham D, Carl D, Jansen C, Khoury JC, Gerson M, Kissela B, Dunning K
Journal of Applied Physiology 2019 Feb;126(2):431-443
clinical trial
5/10 [Eligibility criteria: No; Random allocation: Yes; Concealed allocation: No; Baseline comparability: No; Blind subjects: No; Blind therapists: No; Blind assessors: Yes; Adequate follow-up: Yes; Intention-to-treat analysis: No; Between-group comparisons: Yes; Point estimates and variability: Yes. Note: Eligibility criteria item does not contribute to total score] *This score has been confirmed*

Aerobic exercise may acutely prime the brain to be more responsive to rehabilitation, thus facilitating neurologic recovery from conditions like stroke. This aerobic priming effect could occur through multiple mechanisms, including upregulation of circulating brain-derived neurotrophic factor (BDNF), increased corticospinal excitability, and decreased intracortical inhibition. However, optimal exercise parameters for targeting these mechanisms are poorly understood. This study tested the effects of exercise intensity on acute BDNF and neurophysiological responses. Sixteen ambulatory persons > 6 mo poststroke performed three different 20-min exercise protocols in random order, approximately 1 wk apart, including the following: (1) treadmill high-intensity interval training (HIT-treadmill); (2) seated-stepper HIT (HIT-stepper); and (3) treadmill moderate-intensity continuous exercise (MCT-treadmill). Serum BDNF and transcranial magnetic stimulation measures of paretic lower limb excitability and inhibition were assessed at multiple time points during each session. Compared with MCT-treadmill, HIT-treadmill elicited significantly greater acute increases in circulating BDNF and corticospinal excitability. HIT-stepper initially showed BDNF responses similar to HIT-treadmill but was no longer significantly different from MCT-treadmill after decreasing the intensity in reaction to two hypotensive events. Additional regression analyses showed that an intensity sufficient to accumulate blood lactate appeared to be important for eliciting BDNF responses, that the interval training approach may have facilitated the corticospinal excitability increases, and that the circulating BDNF response was (negatively) related to intracortical inhibition. These findings further elucidate neurologic mechanisms of aerobic exercise and inform selection of optimal exercise-dosing parameters for enhancing acute neurologic effects.

Full text (sometimes free) may be available at these link(s):      help