Do you need a mask while exercising outdoors?

Do you need to wear a mask while exercising outdoors? It depends ...

Despite emerging science that has changed what we know about how the coronavirus is transmitted, there's been one constant over the past year: that outdoors is safer than indoors. But lately that message is getting murky, with Quebec recommending the wearing of masks outdoors, then rescinding the recommendation — kind of — and Ontario locking up tennis courts, banning golf and temporarily closing playgrounds (before opening them again).

So what's changed? Is there new information suggesting that we've been underestimating the strength of virus transmission outdoors? Or is it simply an example of messaging that doesn't reflect the science?

“Part of the problem is the data (about outside transmission) is hard to find,” said Steven Rogak, a mechanical engineering professor at the University of British Columbia who is an expert in aerosols (how viruses and other small particles move through the air).

Indeed, studies of how well the virus spreads outdoors have been limited with conclusions often clouded by the fact that there is no way to fully isolate study subjects to the outdoor environment. Any time spent indoors increases the risk of transmission, making it hard to trace infection to time spent outside. So, while there have been attempts at getting good data, with estimates suggesting that less than 10 per cent of COVID -19 transmission occurred outdoors, the results have been routinely questioned given the inability to unequivocally state the study subjects were infected while outside.

It's this lack of quality information that makes it impossible to say there's no risk of the virus spreading outdoors. But most experts agree it's highly unlikely that two unmasked individuals passing in the street will add to the growing number of positive tests. The same goes for a jogger who is passing a cluster of walkers, four people facing off across a tennis net and a group of golfers playing 18 holes; given the short period of close contact and the surrounding air currents there likely isn't enough of a viral load to result in a successful transfer of the COVID -19 virus from one person to the other.

“Nobody has linked a transmission case to walking or running by someone outdoors,” said Rogak.

But that doesn't mean it can't happen.

“You can still transmit outdoors, you just really have to work at it,” said Matthew Oughton, an attending physician at Montreal's Jewish General Hospital, Division of Infectious Diseases.

Like the indoors, proximity and length of close contact increase the risk of virus transmission in an outdoor setting. So, if you're in the middle of a crowd, sitting at a picnic table with friends for a leisurely catch-up or dining on an outdoor terrace with people who don't live at the same address, a mask is a good idea.

Oughton admits that the lack of consistency in messaging regarding when to wear a mask outdoors is confusing. Yet despite the desire for people to have a single black-and-white directive, there are good reasons for the lack of a universal policy, the first of which is that the level of risk isn't the same across all populations and communities.

Communities with high rates of transmission and/or positive cases, a medical system struggling to keep up with the number of COVID -19 patients who need hospitalization and population density all need to be considered when making policy about whether or not to mask outdoors. But as vaccination rates increase and the number of cases decrease, it's likely that there will be more uniformity not just on whether or not to wear a mask outside, but as to what outdoor sport and recreational activities can be safely resumed.

Both Oughton and Rogak agree that the decision about whether to wear a mask while outdoors is all about evaluating risk.

Individuals working out on their own — walking, cycling, running, hiking — don't need to wear a mask. But if you're exercising or socializing shoulder to shoulder with someone outside of your family unit, wearing a mask outdoors will decrease the risk of virus transmission.

“Cycling in a peloton for an hour seems like a bad idea without a mask,” said Rogak.

As for whether the virus can be transmitted from hard surfaces such as playgrounds, sports equipment and outdoor gyms, the odds are extremely low.

Over the past year there's been a growing understanding that the SARS-COV-2 virus is spread directly from person to person through respiratory droplets or by aerosols that linger in poorly ventilated indoor spaces.

“Most surfaces will sterilize themselves with time,” said Rogak.

Meanwhile, Oughton says it's important to understand the risks of virus transmission in any given outdoor situation and to be prepared in case you unexpectedly find yourself in close contact with someone other than family. “Put a mask in your pocket, and when in doubt, take more precautions than fewer,” he said.

MAJA HITIJ/GETTY IMAGES A group in Berlin plays spike ball during the third wave of the coronavirus pandemic. For many people, outdoor exercise has become vital for maintaining positive well-being during ongoing lockdowns. But there's still the important question of whether those enjoying the outdoors should be masked. Turns out, it's a grey area.

GETTY IMAGES/ISTOCKPHOTO It may be a good idea to wear a mask while exercising outdoors in some situations, writes Jill Barker, even though there isn't conclusive data to prove people have transmitted the virus outside.