Older Adults Slower to Raise Arms During Slips, Increasing Fall Risk: Study Reveals
USA: Older adults may be more susceptible to dangerous falls due to slower arm responses when experiencing a slip, a recent study published in Scientific Reports suggests.
The study, led by Dr. Jonathan S. Lee-Confer from the Department of Physiology at the University of Arizona, investigated how age affects the timing and acceleration of arm movements in response to a slipping incident. The goal was to understand how these movements affect control over the body’s center of mass (CoM)—a key factor in maintaining balance and preventing falls.
Researchers analyzed data from 22 participants, divided evenly between two age groups: younger adults (average age, 25.5 years) and older adults (average age, 72 years). Each individual was subjected to a controlled slip while walking. Researchers then assessed their frontal plane arm motion and how it related to lateral CoM displacement, a marker for balance control.
The following were the key findings of the study:
- Both younger and older adults achieved similar peak arm abduction angles.
- Younger adults reached peak arm abduction significantly faster, averaging 542 milliseconds after the slip, compared to 853 milliseconds in older adults.
- Younger adults demonstrated higher peak arm abduction acceleration, averaging around 3593 degrees/s², whereas older adults averaged approximately 2310 degrees/s².
- Lateral center of mass (CoM) displacement was significantly lower in younger adults, with an average of 4.6 cm, compared to 10.5 cm in older adults.
- Reduced CoM displacement in younger adults indicates better balance recovery and a lower risk of falling.
- A negative correlation was found between arm acceleration and lateral CoM displacement, suggesting that faster arm movement improves stability during a slip.
- Researchers found that every 1000 degrees/s² increase in arm acceleration led to an approximate 2 cm reduction in lateral CoM displacement.
“These results suggest that diminished arm movement speed and acceleration in older adults could impair their ability to maintain balance during slips, thereby increasing their fall risk,” the authors noted.
The findings point to a potential avenue for fall prevention strategies among seniors. Enhancing arm strength and improving neuromuscular responsiveness through targeted exercises could help older individuals react more quickly during balance-threatening events.
Given that seniors were 58% slower at initiating arm movements during slips compared to younger adults, the study underscores the critical role of reaction speed in fall prevention.
With falls being a leading cause of injury in older populations, this research provides valuable insight into how even subtle biomechanical differences can influence safety. Interventions aimed at boosting arm mobility and reaction time may offer a promising approach to reducing fall-related injuries in aging individuals.
Reference:
S., J., Lo, M. K., & Troy, K. L. (2025). Age-Related differences in arm acceleration and center of mass control during a slip incident. Scientific Reports, 15(1), 1-9. https://doi.org/10.1038/s41598-025-00412-9
