Walking is my most frequent form of exercise, so I’ve noticed that online maps are a little suspect as far as providing good time estimates.
Such discrepancies reflect teething problems for the growing industry of providing walking times. “It’s largely not a problem that anyone has solved in the world perfectly,” says Manik Gupta, senior product manager at Google Maps in Mountain View, Calif., about walking-time estimates.
Estimation of walking times poses many questions: How fast do people walk and how much does it vary? How do hills and traffic lights affect speed? Do popular walks—say through city centers—vary in time according to time of day, slowing down when other walkers congest the routes?
Various walking-time providers answer these questions differently. Their assumptions of walking speed can vary from 2.5 miles per hours to 3.1 miles per hour, and their treatments of hills varies, too. Some assume a walk in a crowded urban area will be slower than in a park, while others ignore stops at traffic lights. And most aren’t yet adjusting for congestion—a big factor when walking among thousands of spectators to Olympic venues.
Google didn’t disclose what baseline walking speed it assumes, saying journey times vary anyway based on other factors. Jim Stone, executive director of walking-advocacy group WalkSanDiego, says he has found Google can say a mile will take anywhere from 15 to 30 minutes, depending on the details of the route.
Walkit, a U.K. walk-routing website, adjusts for hills using Naismith’s Rule, developed by William W. Naismith, a Scottish mountaineer, in 1892. The rule adds time for uphill stretches, proportional to the elevation gained; subtracts time for downhill walks at light slopes; and adds times for steep downhill treks. The site also provides three options for walking speed—slow (two miles per hour), medium (3 mph) and fast (4 mph).
Time estimates can surprise infrequent walkers. “People think that a mile sounds really far,” says a TfL spokeswoman. “You say a mile, and they say, ‘That’s forever!’ But say it’s 20 minutes, and they say, ‘That’s achievable.’ “
How long walkers remember a journey taking can depend on factors other than time, such as variety of scenery, says Barbara McCann, founder of Washington, D.C., nonprofit National Complete Streets Coalition, which advocates street design that accommodates all users, in addition to cars. “It’s nice to provide walk times for people,” says Ms. McCann, now an independent consultant, “but you have to be aware it’s a super-subjective thing.”
(click here to continue reading Timing an Urban Stroll Isn’t a Walk in the Park – WSJ.com.)
I’ve also noticed that I walk faster when walking by myself, with just headphones, music and camera(s). Walking with someone, or with a group, inevitably slows everyone down.