Age-Related Decline of Wrist Position Sense and its Relationship to Specific Physical Training

Abstract

Perception of limb and body positions is known as proprioception. Sensory feedback, especially from proprioceptive receptors, is essential for motor control. Aging is associated with a decline in position sense at proximal joints, but there is inconclusive evidence of distal joints being equally affected by aging. In addition, there is initial evidence that physical activity attenuates age-related decline in proprioception. Our objectives were, first, to establish wrist proprioceptive acuity in a large group of seniors and compare their perception to young adults, and second, to determine if specific types of training or regular physical activity are associated with preserved wrist proprioception. We recruited community-dwelling seniors (n = 107, mean age, 70 ± 5 years, range, 65-84 years) without cognitive decline (Mini Mental State Examination-brief version ≥13/16) and young adult students (n = 51, mean age, 20 ± 1 years, range, 19-26 years). Participants performed contralateral and ipsilateral wrist position sense matching tasks with a bimanual wrist manipulandum to a 15° flexion reference position. Systematic error or proprioceptive bias was computed as the mean difference between matched and reference position. The respective standard deviation over five trials constituted a measure of random error or proprioceptive precision. Current levels of physical activity and previous sport, musical, or dance training were obtained through a questionnaire. We employed longitudinal mixed effects linear models to calculate the effects of trial number, sex, type of matching task and age on wrist proprioceptive bias and precision. The main results were that relative proprioceptive bias was greater in older when compared to young adults (mean difference: 36% ipsilateral, 88% contralateral, p < 0.01). Proprioceptive precision for contralateral but not for ipsilateral matching was smaller in older than in young adults (mean difference: 38% contralateral, p < 0.01). Longer years of dance training were associated with smaller bias during ipsilateral matching (p < 0.01). Other types of training or physical activity levels did not affect bias or precision. Our findings demonstrate that aging is associated with a decline in proprioceptive bias in distal arm joints, but age does not negatively affect proprioceptive precision. Further, specific types of long-term dance related training may attenuate age-related decline in proprioceptive bias.

Keywords: adult; dancing; exercise; human; position sense; proprioception; sensorimotor; wrist.

Figure 1

Wrist bimanual manipulandum. Active ipsilateral and contralateral wrist position sense matching of a 15° reference wrist flexion position is performed with occluded vision. Consent was obtained from the individual for the publication of this image.

Figure 2

Plot of overshoot/undershoot bias in older and young adults. Proprioceptive bias for both joint position matching tasks. Dots placed at the 0° position would indicate a perfect match. Note that both young and older adults tended to overestimate the 15° reference position. Each data point represents the mean of values for a single participant.

Figure 3

Relative frequency distribution for signed bias. Mean and standard deviation histograms for signed bias and precision during active ipsilateral and contralateral wrist position sense matching. Relative frequency distribution of mean outcomes of proprioceptive signed bias in older (red) and young adults (blue), expressed in percentages. Note that the distribution for the older adults is shifted to the right, indicating a higher bias. Means and standard deviations of contra- and ipsilateral signed bias and precision (in degrees) are shown in the respective bar graphs, with a * indicating a significant difference, p < 0.05.

Figure 4

Distribution plots showing proprioceptive signed bias of all trials for contralateral and ipsilateral matching in young and older females and males. Proprioceptive bias for both joint position matching tasks. Each dot represents a single trial. The dots are randomly jittered to avoid point spatial overlap. The degree of error in proprioceptive bias is represented for each type of task, sex, and age group. The colored boxes represent the mean and standard deviation of the proprioceptive signed bias for the type of task sex and age group.

Figure 5

Distribution plots of proprioceptive precision for contralateral and ipsilateral matching in young and older females and males. Proprioceptive precision over the 5 trials/task for both joint position matching tasks. The dots are randomly jittered to avoid point spatial overlap. The degree of error in proprioceptive precision is represented for each type of task, sex, and age group. The colored boxes represent the mean and standard deviation of the proprioceptive precision for the type of task, sex and age group.

Figure 6

Effect of years of dance training on ipsilateral and contralateral bias. Scatter plot of proprioceptive bias during a contralateral (blue) or ipsilateral (red) matching task in young and old adults, with data plotted against years of dance training. The regression lines show the association between years of dancing and proprioceptive bias in both matching tasks.