Pedestrian Crossing Ahead

Pedestrian Crossing Ahead

Characterising Walking Patterns in the Lab Setting
Health-care practitioners recommend walking for its many benefits. Some benefits, such as muscle strength, and endurance1, are obvious. But walking can also contribute to psychosocial wellbeing through social interaction and community engagement2.  These factors are especially important for older adults. Yet there may be some hidden challenges to walking within a community such as crossing the street. Depending on the neighbourhood “built environment," crosswalks can be hectic, filled with distractions. Meeting the time demands of the crosswalk can be difficult for older pedestrians3, especially those with mobility challenges.

Measuring Community Mobility
Understanding a person’s response to a crosswalk scenario, in a lab setting, provides the opportunity to explore the person-environment interaction under controlled conditions. We investigate community mobility in older adults, and in particular, we want to know how the built environment may support or challenge older adults.

In our study, we first assessed older adults who have few challenges with outdoor walking. We did this in a lab setting. This knowledge provides a foundation for future work with more vulnerable populations, such as older adults who have mobility limitations, and/or those who use walkers or other mobility devices. 

Fortunately, the technology exists to assess walking patterns in a safe environment. We used advanced instruments like the GAITrite mat4 to gather accurate data. We asked a group of community-dwelling older adults to participate in lab-based walking trials. Participants walk at their usual, slow, and fast paces, and we used GAITrite to gather baseline information.  We then simulated the crosswalk experience by adding a pedestrian signal that switched from a “don’t walk” to “walk."

The information we gathered will help us to develop and conduct studies in the "real world."  For example, we could measure community mobility among older adults with lower extremity injury; or investigate how older adults respond to crowded sidewalks, crossings or other complex features in the built environment.

Lab-based Study
In our recently published paper5, we invited 22 community dwelling older men and women to take part in a lab-based study. The study included four trial conditions: walking at their slow, usual and fast paces and walking under a crosswalk scenario. Our sample of older adults had a usual walking pace of 1.41 m/s, which aligns with the guidelines for city crosswalks designed for a walking speed of 1.2 m/s6.

However, in the crosswalk condition, participants walked faster at 1.44m/s, and with greater inconsistency in their walking pattern. We call this "gait variability." Participants had greater step length variability (irregular distances between steps), and more step time variability (inconsistent time taken to complete each step) in the crosswalk simulation. This may be an instinctive response when walking in any situation other than “usual”, as we also observed slightly higher variability in walking patterns when participants chose a slow pace (mean speed 0.99 m/s) or fast pace (mean speed 1.74 m/s).

Even in this lab-based crosswalk simulation, where timing demands and distractions were absent, we noted a change in walking speed and variability. This is notable because there is a connection between gait variability and an increased risk of falls7. Falls are a serious concern for all, but especially for older adults.

This man is having his gait assessed for research using
the GAITrite mat at the Centre for Hip Health and Mobility.

Beyond the Lab

We also wanted to gather information about our participants' perceptions about their own neighbourhoods. So another component to our study was self-report measures of community mobility, and perceived walkability and safety of the participants’ neighbourhoods.

The majority of participants reported leaving their home on a daily basis. Most participants reported leaving for ‘activities of daily living.’  Some participants also reported visiting friends and participating in recreational programs. This supports the notion that mobility is central to social engagement in the community.

 Many reported that they had destinations within walkable distance of their homes, such as stores or public transit. Another factor identified as an enabler of community mobility was good infrastructure. Although the majority of participants agreed that sidewalks and crosswalks were present in their neighbourhoods, 6 of our 22 participants reported feeling unconfident about their safety when crossing the road. These findings generate hypotheses for future work on apprehension about crossing the street and changing walking pattern to accommodate obstacles.

Our thanks to the study participants who provided the opportunity for us to explore these important issues related to community mobility.

References

  1. Simons R. The effects of resistance training and walking on functional fitness in advanced old age. Journal of Aging and Health. 2006;18(1):91.
  2. Van Cauwenberg JJ. Relationships between the perceived neighbourhood social environment and walking for transportation among older adults. Social Science & Medicine. 2014;104:23-30.
  3. Hoxie RE, Rubenstein LZ. Are older pedestrians allowed enough time to cross intersections safely? Journal of the American Geriatrics Society. 1994;42:241-4.
  4. http://www.hiphealth.ca/blog/Walk-of-life
  5. Brown KC, Hanson HM, Firmani F, Liu D, McAllister MM, Merali K, Puyat JH, Ashe MC. Gait speed and variability for usual pace and pedestrian crossing conditions in older adults using the GAITRite walkway. Gerontology and Geriatric Medicine January-December 2015 1, first published on December 4, 2015.
  6. Transportation Association of Canada. Manual of uniform traffic control devices for Canada, 4th ed. 1998, Section B4.1.1.
  7. Hausdorff JM, Rios DA, Edelberg HK. Gait variability and fall risk in community-living older adults: A 1-year prospective study. Archives of Physical Medicine and Rehabilitation. 2001;82:1050-6.