Researchers at Emory University have discovered that excessive brain and muscle activity during minor balance disruptions contributes to poorer balance recovery in older adults, including those with Parkinson's disease. The study, published in eNeuro, reveals that trying harder to balance may actually increase fall risk. Opposing muscles stiffening simultaneously further impairs stability.
Lena Ting of Emory University and colleagues investigated how aging and Parkinson's disease influence balance responses. In prior experiments with young adults, sudden destabilization—like pulling a rug from under their feet—triggered rapid brainstem and muscle reactions, followed by stronger brain-involved responses for severe challenges. The new study focused on older adults with and without Parkinson's, using similar perturbations. They observed heightened brain responses and muscle activity even for minor disruptions. Ting stated, 'Balance recovery takes more energy and engagement from the brain in these populations. We found that, when people require more brain activity to balance, they have less robust ability to recover their balance.' A notable pattern emerged: activating one muscle for stabilization often caused the opposing muscle to co-contract, creating stiffness that reduced movement efficiency and correlated with worse balance performance. The findings suggest this overactivity, rather than underactivity, underlies many balance problems. Ting added, 'We may be able to determine whether someone has increased brain activity simply by assessing muscle activity after pulling a rug out from under you.' The team, including Scott E. Boebinger, Aiden M. Payne, Jifei Xiao, Giovanni Martino, Michael R. Borich, and J. Lucas McKay, published their work in eNeuro (DOI: 10.1523/ENEURO.0423-25.2026). They propose refining the method to identify at-risk individuals early, enabling targeted training to prevent falls.