Takebayashi H1, Takimoto K1, Okuda T1, Miyamoto K1, Takuma Y1, Inoue Y1, Miyamoto S1, Okabe T1, Watanabe I1
1Tosa Rehabilitation Collge, Physical Therapy, Kochi, Japan
Background: In daily living, we perform coincidence timing tasks to coincide with a variety of external factors. Previous studies examined static coincidence timing tasks, but few studies have reported the effects of dynamic factors and aging.
Purpose: We examined changes in static and dynamic coincidence timing due to aging and their association with falls.
Methods: Subjects were 30 healthy young adults（mean age, 21.6±2.0 years）and 30 older adults (mean age, 74.7±5.4 years). Older adults were divided into a fall group (n=8; mean age, 76.1±8.0 years; one fall in the past year) and a no-fall group (n=22; mean age, 74.2±4.0 years; no falls).
Subjects were asked to observe 5 lamps placed in a row at 3 cm intervals at a distance of 2 m (from the subjects) and a height of 1 m, and to perform a static task (pressing a button) and a dynamic task (jumping onto a sensor mat) coincident with lighting of the 5th lamp. The lamps were lit starting from the 1st lamp (placed at a 45-degree angle to the right of the subject) and moving at 0.5 second intervals toward the 5th lamp (placed in front of the subject).
Each task was measured using a multipath system (DKH, Tokyo, Japan), and the mean of 3 valid measurements was used to calculate timing error (absolute error). Two-way analysis of variance ANOVA with repeated measurements and multiple comparisons were used to compare the values of absolute error for the static and dynamic tasks between young and older adults (fall and no-fall groups). Significance was set at 5%.
Results: The coincidence timing error was significantly larger for the dynamic task compared with the static task (p 0.01) in the young adult group and the fall group, but not in the no-fall group. For the static task, the error was significantly larger (p 0.01) in the fall and no-fall groups compared with the young adult group. In addition, the error was largest in the fall group, although no significant difference was observed between the fall and the no-fall groups. For the dynamic task, the error was largest in the fall group. No significant difference was observed between the young adult group and the no-fall group, while significant differences (p 0.01) were observed between both the young adult and no-fall groups and the fall group.
Conclusion(s): The larger error observed in the older adult group compared with the young adult group for the static task indicates a significant effect of increasing age on the performance of the task. No significant difference in error was observed between the static and dynamic tasks in the no-fall group, whereas there was significantly larger error for the dynamic task compared to the static task in the fall group. These results suggest an association of dynamic coincidence timing with falls.
Implications: Error in coincidence timing tasks increases with increasing age. Our results show that dynamic coincidence tasks associate closely with falls and may be important in assessment and training.
Keywords: coincidence timing, aging, fall
Funding acknowledgements: The authors have no conflicts of interest to declare.
Purpose: We examined changes in static and dynamic coincidence timing due to aging and their association with falls.
Methods: Subjects were 30 healthy young adults（mean age, 21.6±2.0 years）and 30 older adults (mean age, 74.7±5.4 years). Older adults were divided into a fall group (n=8; mean age, 76.1±8.0 years; one fall in the past year) and a no-fall group (n=22; mean age, 74.2±4.0 years; no falls).
Subjects were asked to observe 5 lamps placed in a row at 3 cm intervals at a distance of 2 m (from the subjects) and a height of 1 m, and to perform a static task (pressing a button) and a dynamic task (jumping onto a sensor mat) coincident with lighting of the 5th lamp. The lamps were lit starting from the 1st lamp (placed at a 45-degree angle to the right of the subject) and moving at 0.5 second intervals toward the 5th lamp (placed in front of the subject).
Each task was measured using a multipath system (DKH, Tokyo, Japan), and the mean of 3 valid measurements was used to calculate timing error (absolute error). Two-way analysis of variance ANOVA with repeated measurements and multiple comparisons were used to compare the values of absolute error for the static and dynamic tasks between young and older adults (fall and no-fall groups). Significance was set at 5%.
Results: The coincidence timing error was significantly larger for the dynamic task compared with the static task (p 0.01) in the young adult group and the fall group, but not in the no-fall group. For the static task, the error was significantly larger (p 0.01) in the fall and no-fall groups compared with the young adult group. In addition, the error was largest in the fall group, although no significant difference was observed between the fall and the no-fall groups. For the dynamic task, the error was largest in the fall group. No significant difference was observed between the young adult group and the no-fall group, while significant differences (p 0.01) were observed between both the young adult and no-fall groups and the fall group.
Conclusion(s): The larger error observed in the older adult group compared with the young adult group for the static task indicates a significant effect of increasing age on the performance of the task. No significant difference in error was observed between the static and dynamic tasks in the no-fall group, whereas there was significantly larger error for the dynamic task compared to the static task in the fall group. These results suggest an association of dynamic coincidence timing with falls.
Implications: Error in coincidence timing tasks increases with increasing age. Our results show that dynamic coincidence tasks associate closely with falls and may be important in assessment and training.
Keywords: coincidence timing, aging, fall
Funding acknowledgements: The authors have no conflicts of interest to declare.
Topic: Older people; Human movement analysis; Outcome measurement
Ethics approval required: Yes
Institution: Tosa Rehabilitation College
Ethics committee: Independent Ethics Committee
Ethics number: TRC101606
All authors, affiliations and abstracts have been published as submitted.
