A Comparative Study of Adjustability of Grasping Force between Young People and Elderly Individuals

Abstract

This study aimed to compare adjustability of grasping force (AGF) between people belonging to young and elderly age-groups. Methods: Twenty young people and 20 elderly people, with no previous pathology involving the hands and fingers, were included in the study, and an AGF assessment was performed for all the subjects using an iWakka. Subjects adjusted the grasping force according to the target value displayed on the monitor by opening or closing the iWakka. Results: The assessment of AGF was performed separately from that of the gripping force, and the latter was found to be comparable between the two groups. The mean AGF was found to be 8.9 ± 4.0 g and 7.6 ± 2.8 g for the dominant and the non-dominant hand, respectively, in the elderly group, as compared to the mean AGF for the dominant and the non-dominant hand of 4.4 ± 1.2 g and 4.4 ± 0.6 g, respectively estimated in the young age-group. A t-test conducted after controlling the disparate factors (sex, handedness, gripping force) between the subjects of the two groups, showed that there was a significant difference in AGF between the young and the elderly groups for both the dominant (p = 0.03) and the non-dominant hand (p = 0.02), indicating that the AGF of the elderly people was significantly lower than that of the young study-subjects. Conclusions: Our findings suggest that AGF decreases with aging and that it is necessary to assess AGF separately from the gripping force, to make a precise comparison.

A study on how concurrent visual feedback affects motor learning of adjustability of grasping force in younger and older adults

“…Finally, Kaneno et al 2 reported that the older adult had lower AGF than younger individuals in situations in which concurrent visual feedback was used, as in the acquisition phase of this study. The authors state the need for an intervention regarding this ability.…”

“…Older adults have been reported to perform worse than younger people in AGF tasks using visual information 2 , 3 . However, the effect of the ability to properly adjust the grasping force without relying on external information and the speed to reflect visual information in movement has not been investigated.…”

“…In this study, iWakka (Aimu Co., Ltd.) was used to measure AGF based on a report by Kaneno 2 , 3 (Fig. 1 ).…”

“…It is known that older adults have less ability to maintain stable force, and that upper limb function declines with ageing 1 . Previous studies have defined this ability as the adjustability of grasping force (AGF) and reported that older people showed lower AGF than younger people 2 , 3 . It has been reported that dexterity of the upper limbs is associated with activities of daily living (ADL) using evaluations of upper limb function 4 , 5 .…”

Relationship between the adjustability of grasping force and upper limb/hand function evaluation in individuals with cerebrovascular disorders: a preliminary cross-sectional study

“…1B). A previous study involving healthy older adults reported that the AGF differed depending on each section, requiring different adjustment methods for each interval [15]. Therefore, this study aimed to obtain insights into the task characteristics of adjustment by calculating the AGF (g) for the total sections and each section individually.…”