Precision grip force control of older and younger adults, revisited.

Abstract

This study revisited the hypothesis that older adults lose some ability to efficiently control precision grip force. A previous study demonstrated such a decrement in older adults' performance in a vertical lift and support maneuver. This study employed a similar paradigm in which dynamic forces were applied with a simulated hand tool while measuring grip force and force applied with the tool. Measures of grip force control reflected subjects' modulation of grip force in parallel with force transmitted with the tool and their scaling of the ratio of grip to applied force. Nine older (> 65 years) and 9 younger (< 65 years) subjects' grip force control measures were compared with emphasis on recruiting active older individuals for whom upper extremity usage was high in their daily life. No statistically significant age effects were found in either force control measure, suggesting a smaller age-related decrement than reported in a previous study.