The effect of physical fatigue on oscillatory dynamics of the sensorimotor cortex

Fry, Adam; Mullinger, Karen J.; O'Neill, George C.; Brookes, Matthew J.; Folland, Jonathan P.

Abstract

Aim: While physical fatigue is known to arise in part from supraspinal mechanisms within the brain exactly how brain activity is modulated during fatigue is not well understood. Therefore, this study examined how typical neural oscillatory responses to voluntary muscle contractions were affected by fatigue.
Methods: Eleven healthy adults (age 27±4 years) completed two experimental sessions in a randomised crossover design. Both sessions first assessed baseline maximal voluntary isometric wrist-flexion force (MVFb). Participants then performed an identical series of fourteen test contractions (2 × 100%MVFb, 10 × 40%MVFb, 2 × 100%MVFb) both before and after one of two interventions: forty 12-s contractions at 55%MVFb (fatigue intervention) or 5%MVFb (control intervention). Magnetoencephalography (MEG) was used to characterise both the movement-related mu and beta decrease (MRMD and MRBD) and the post-movement beta rebound (PMBR) within the contralateral sensorimotor cortex during the 40%MVFb test contractions, while the 100%MVFb test contractions were used to monitor physical fatigue.
Results: The fatigue intervention induced a substantial physical fatigue that endured throughout the post-intervention measurements (28.9-29.5% decrease in MVF, P<0.001). Fatigue had a significant effect on both PMBR (ANOVA, session × time-point interaction: P=0.018) and MRBD (P=0.021): the magnitude of PMBR increased following the fatigue but not the control interventions, whereas MRBD was decreased post-control but not post-fatigue. Mu oscillations were unchanged throughout both sessions.
Conclusion: Physical fatigue resulted in an increased PMBR, and offset attenuations in MRBD associated with task habituation.

Citation

Fry, A., Mullinger, K. J., O'Neill, G. C., Brookes, M. J., & Folland, J. P. (2018). The effect of physical fatigue on oscillatory dynamics of the sensorimotor cortex. Acta Physiologica, 220(3), 370-381. https://doi.org/10.1111/apha.12843

• Journal Article Type: Article
• Acceptance Date: Dec 7, 2016
• Online Publication Date: Jan 29, 2017
• Publication Date: Jul 1, 2018
• Deposit Date: Dec 20, 2016
• Publicly Available Date: Jan 29, 2017
• Journal: Acta Physiologica
• Print ISSN: 1748-1708
• Electronic ISSN: 1748-1716
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 220
• Issue: 3
• Pages: 370-381
• DOI: https://doi.org/10.1111/apha.12843
• Keywords: magnetoencephalography; MEG ; motor; sensory; mu; beta; event-related desynchronization; event-related synchronization
• Public URL: https://nottingham-repository.worktribe.com/output/960983
• Publisher URL: http://onlinelibrary.wiley.com/doi/10.1111/apha.12843/abstract
• Additional Information: This is the peer reviewed version of the following article: The effect of physical fatigue on oscillatory dynamics of the sensorimotor cortex / Adam Fry, Karen J. Mullinger, George C. O'Neill, Matthew J. Brookes and Jonathan P. Folland, which has been published in final form at http://dx.doi.org/10.1111/apha.12843. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
• Contract Date: Dec 20, 2016