The Relationship Between Upper Extremity Strength and Forward Fall Arrest Capacity in Older Women

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Abstract

Background: Older adults, especially women, are at risk of injury following a fall. Forward falls account for the majority of falls in community-dwelling adults. Reaching forward with the arms to fall on an outstretched hand is a common protective strategy used to mediate injuries to the upper body, torso and head.

Purpose: Examine the utility of novel measures of upper body strength and determine the relationship of upper body strength to successful forward fall arrest landing on outstretched hands in older women.

Methods: Participants, aged 60 years or older, were recruited from the local community. In study one, test-retest reliability and concurrent validity of novel multi-joint functional clinical upper body strength measures, compared to more traditional strength measures, were determined in 6 men and 11 women (71 ± 10 yrs). Using a unique simulated fall arrest apparatus developed by our research team, study two explored the relationship of physical function and upper body strength to upper limb pre-impact reaction and movement time in 75 women (72 ± 8 yrs). Study three investigated the age differences in upper extremity joint moments and upper limb strength during a simulated forward fall arrest in 68 women (70 ± 8 yrs).

Results: Excellent test-retest reliability (all ICC > 0.90, p < 0.001) for novel and traditional upper limb strength measures, with good to high significant correlations between all strength measures (all r > 0.8, p < 0.001). In study two, a relationship between stronger handgrip (r² = 0.08, p = 0.013) and faster reaction time was shown, accounting for 8% of the variance. Secondly, greater shoulder flexion strength (r² = 0.06, p = 0.036) was related to faster movement time, explaining 6% of the variance. Study three demonstrated percentage joint moment contributions differed between women in their sixties and seventies with significantly greater shoulder joint involvement (p = 0.008), coupled with lower elbow joint contributions (p = 0.004) in comparison to women in their eighties.

Findings: This thesis advanced the feasibility and utility of novel measures of upper body strength in older adults and further highlighted a relationship between two important modifiable components (strength and speed) that may contribute to successful pre-impact arm responses, fall arrest and descent to reduce injury risk during a forward fall. The findings support future investigation to determine if fall prevention and exercise prescription interventions focused on improving reaction time, movement time and upper extremity strength contribute to successful forward landings to prevent injury. This thesis highlights the importance of modifiable factors in forward fall arrest strategies.

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Cited By (1)

Year	Entry
2022	Pifko JW. Simulated Fall Arrest Upper Extremity Biomechanics and Strength Relationships in Healthy Older Males and Females [Master's thesis]. University of Saskatchewan; June 2022.