Influence on Probe Reaction Time of Rhythmic Stabilization during Sitting

Abstract

[Purpose] This study examined the influence of the probe reaction time on sitting stability during rhythmic stabilization. [Subjects] The subjects were divided into two groups of thirty-three elderly subjects (70.0 ± 6.0 years), and ten younger subjects (22.4 ± 2.8 years). [Methods] We evaluated the simple reaction time, the probe reaction time during rhythmic stabilization, and the resistance force of rhythmic stabilization. [Results] The probe reaction time was significantly longer than the simple reaction time in both groups. The resistance force of rhythmic stabilization decreased in the Elderly group compared with the Younger group. Partial correlation analysis gave correlations of r = 0.87 for the probe reaction time, r = 0.87 for the simple reaction time, r = -0.34 for the probe reaction time and the resistance force, and r = 0.80 for the probe reaction time and the ΔRT (ΔRT= probe reaction time - simple reaction time). [Conclusion] The results suggest that not only the trunk muscle force but also the attention are factors influencing the sitting stability.