The problem with your virtual race PB

A lot of runners have earned PBs during their races-without-races this season as we pivoted from in-person events to virtual runs. The problem is that the times we’re recording aren’t accurate and we could be doing ourselves a disservice when we step back on the line at an actual measured race course. Due to the nature of GPS watches, our virtual finishes could be reporting times that are as much as 10% quicker than we’ve actually run. 

“In my last race, I ran a marathon on a 5km loop that had a bunch of gentle 90-degree turns. My GPS said I ran 64:05 when I actually ran 65:16 for 21.1km,” says Reid Coolsaet, the two-time Olympian and run coach who’s been explaining to his athletes why they shouldn’t get hung up on times being uploaded to Strava by their peers. “If you record a good time on a course with lots of turns you may have a hard time replicating that time on a properly measured course. In reality, you may be running just as fast once races open up, but your finish time could be slower and that’s demoralizing when you’re putting forth the same effort.”

Make no mistake: virtual races are awesome and every PB is worth celebrating. In fact, every finish is worth celebrating, regardless of your time. We’re not disputing that. We’re applauding everyone’s effort, and #MyRaceisReal, a popular virtual racing hashtag, has popped up on social media and many athletes on the iRun Facebook page have scored hard-earned virtual race personal best finishing times.

“I’ve run enough virtuals that I now have virtual PRs to try to break,” Meghan Braithwaite said. “That said, #MyRaceIsReal and I still put a good effort into them. My marathon isn’t less valid because it was virtual.” 

Dan Suher, the global sales director of COROS wearables, has long been interested in how GPS watches work and his company was first to put a course-correcting feature for the track on their watch in 2019. “When the watch stays on one side of your body and you pivot the way you do when you run around a track, the GPS antenna has trouble cleanly interacting with the satellites and the data gets skewed,” says Suher, adding that what lane you’re in on a track can also affect your watches appraisal of your finishing distance and time. “Your GPS watch is interacting with the satellites on average every 1 to 3 seconds (depending on the brand and mode) and it’s squaring rather than curving in its record of your data. The time being recorded is based upon a straight line, which is shorter than points on a circle, and so the numbers are off.”

To offset the faulty data, COROS has a function called “Track Run-mode,” which creates an algorithm for the GPS satellite and helps it configure your time and distance based upon what lane you’re running on the track. Bernard Conway, a longtime grade-A course measurer for such events as the Pan Am games, the Scotiabank Toronto Waterfront Marathon, and races from Philadelphia to Cuba to Buffalo to Niagara Falls, says the virtual races are a soon-to-be boon to business. Conway knows that the virtual runners of today are the same racers who will be out on his certified courses tomorrow. He timed his first race course with a Jones counter on his bicycle in 1972 and plans to ride his bicycle to measure more courses once Canada can return to large-scale racing events. He just doesn’t want virtual racers to finish his events disappointed. 

Coolsaet says not to put too much stock in a virtual course that has a lot of turns if you’re measuring your time and distance with your GPS watch. “If it’s a virtual race then it’s fun to shoot for a time and it’s a great training stimulus and it bridges the gap to normal races,” he says, which is a nice way of saying: that Boston Marathon-qualifying finish may not hold up to close scrutiny and it’s going to be harder when you try and break three-hours again in Ottawa, Vancouver, Calgary, Halifax or any properly-measured race course.

However, Tina Perilli, pictured, who has run nine virtual races since the Chilly Half Marathon in 2020, one month before COVID-19, says she’s scored seven virtual PBs and she’s proud of each one. “To me, it’s a PB regardless,” Perilli says, adding that she’s dropped as much as 12 minutes off her marathon time and 4 minutes off her 30K finish at Around the Bay. Of course, if you’re breaking your records by those kinds of margins, the tiny discrepancies hardly matter. What’s more, Perilli says the virtual events may even be worth more than in-person races. She says they require more effort. “I think when you’re all alone and have no one to chase, the race is even harder,” she says. “A virtual race takes more effort because you don’t have anyone rooting you on.”