Acute and chronic exercise influence serum brain‐derived neurotrophic factor in multiple sclerosis

Exercise has been shown to increase neurotrophin production in the brain and spinal cord and may be an effective countermeasure to minimize deleterious changes associated with neurodegenerative diseases such as multiple sclerosis (MS). We studied the acute and chronic impact of 8 weeks of aerobic exercise on serum brain‐derived neurotrophic factor (BDNF) in MS and matched controls. Eleven MS subjects and eleven healthy controls matched for age, weight, height, percent body fat and VO 2peak completed the study. Subjects performed 30 minutes of cycle ergometry at 60% of VO 2peak , three times a week for 8 consecutive weeks. Resting serum BDNF was lower in MS compared to controls at week 0 (p=0.03) and only tended to be lower at week 8 (p=0.07). Resting BDNF concentration in controls remained unchanged throughout the training intervention. However, resting BDNF increased at week 4 in MS subjects (p=0.04). Both MS and controls showed decreases in BDNF during a 3‐hour recovery following a single bout of exercise (p<0.001) but these responses were different between groups (p=0.01). Our study provides new evidence that exercise training may modulate BDNF at rest in MS. A single bout of exercise may also stimulate clearance of circulating BDNF. Further investigation is warranted to clarify the significance of these changes on neuroprotection. Supported by a National Multiple Sclerosis Society Grant