Analysis of a Self-Regulating Method for Determining Acceptable Finger Force Limits

Abstract

In contrast to previous work using the psychophysical methodology, participants in the present work were instead asked to self-adjust and self-regulate their exertion level during simple finger exertions aimed at deriving maximum acceptable limits (MALs). Three methods to determine MALs from a sequence of exertions are described and compared. The effects of trial durations and intersession repeatability were also investigated. All analysis methods produced comparable MAL estimates, within 0.5 N. MALs obtained from the first 5 minutes of data were 2.2% higher than those from the entire 25-minute session, but this difference was not significant. Differences between sessions averaged 4%, which was not significant. The results suggest the self-regulating method can produce repeatable estimates of subjective finger force limits, that these limits are insensitive to the analysis method used for determination, and that it may be possible to obtain repeatable values with relatively brief experimental sessions.