Relationships among Jump Motion Control Ability, Knee Joint Position Sense, and Adjusting Muscle Contraction in Healthy Subjects

How long can joint position sense be retained in memory by young healthy subjects?

[Purpose] The aim of the present study was to investigate how long joint position sense (JPS) can be retained in memory. [Subjects] Eleven healthy subjects (5 men and 6 women) were enrolled in this study. [Methods] Subjects memorized a specific joint position visually, and then they were asked to reproduce without visual aid the position at 3 different time intervals: immediately, 5 minutes post-memorization, and 30 minutes post-memorization. [Results] Differences in JPS between time intervals of immediate and 30 minutes post-memorization were statistically significant with the exception of knee flexion at 60° with a 5 kg load. Differences in reproduced JPS between time intervals of immediately and 5 minutes post-memorization were not statistically significant. [Conclusions] The results suggest that JPS can be retained in memory for approximately 5 minutes.