Older adults must hurry at pedestrian lights! A cross-sectional analysis of preferred and fast walking speed under single- and dual-task conditions

Abstract

Slow walking speed is strongly associated with adverse health outcomes, including cognitive impairment, in the older population. Moreover, adequate walking speed is crucial to maintain older pedestrians' mobility and safety in urban areas. This study aimed to identify the proportion of Swiss older adults that didn't reach 1.2 m/s, which reflects the requirements to cross streets within the green-yellow phase of pedestrian lights, when walking fast under cognitive challenge. A convenience sample, including 120 older women (65%) and men, was recruited from the community (88%) and from senior residences and divided into groups of 70-79 years (n = 59, 74.8 ± 0.4 y; mean ± SD) and ≥80 years (n = 61, 85.5 ± 0.5 y). Steady state walking speed was assessed under single- and dual-task conditions at preferred and fast walking speed. Additionally, functional lower extremity strength (5-chair-rises test), subjective health rating, and retrospective estimates of fall frequency were recorded. Results showed that 35.6% of the younger and 73.8% of the older participants were not able to walk faster than 1.2 m/s under the fast dual-task walking condition. Fast dual-task walking speed was higher compared to the preferred speed single- and dual-task conditions (all p < .05, r = .31 to .48). Average preferred single-task walking speed was 1.19 ± 0.24 m/s (70-79 y) and 0.94 ± 0.27 m/s (≥80 y), respectively, and correlated with performance in the 5-chair-rises test (rs = -.49, p < .001), subjective health (τ = .27, p < .001), and fall frequency (τ = -.23, p = .002). We conclude that the fitness status of many older people is inadequate to safely cross streets at pedestrian lights and maintain mobility in the community's daily life in urban areas. Consequently, training measures to improve the older population's cognitive and physical fitness should be promoted to enhance walking speed and safety of older pedestrians.

Fig 1. Percentage of women and men walking slower than 1.2 m/s.

The graphs represent each of the four walking conditions (A–D). DT, dual-task; ST, single-task.

Fig 2. Walking speed under the four walking conditions.

Mean walking speed was higher in the younger age group in all four respective walking conditions (all p < .001). Mean values of adjacent boxplots in the respective age group are significantly different (all p < .05). The dashed green line represents the required 1.2 m/s walking speed to cross streets safely within the green–yellow phase of pedestrian lights. DT, dual-task; ST, single-task.

Fig 3. Association between fast single-task walking speed and performance in the 5-chair-rises test.

The gray line represents the regression line (y = 20.53 − 6.09 × x, R² linear = 0.310).