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Remember, long ago, when you used to have to walk all the way down the hallway, and perhaps even up or down a flight of stairs, to get to that meeting?
“Now, I just jump from Zoom meeting to Zoom meeting,” says Jonathan Little, who heads the Exercise, Metabolism and Inflammation Lab at the University of British Columbia’s Okanagan Campus, but is currently working from his kitchen table. “I’m probably sitting a lot more than normally.”
That’s a problem, because long bouts of uninterrupted sitting have emerged over the past decade as a harbinger of future health problems such as diabetes and heart disease. Little’s latest study explores the potential of ultrabrief “exercise snacks” to counteract these negative effects. The good news is that it works. But the trickier part, as Little himself knows first-hand, is getting people to change their desk-bound behaviour.
Little’s new study, which was published with colleagues at UBC and the University of Saskatchewan in Medicine and Science in Sports and Exercise, builds on an exercise snacks protocol published last year by McMaster University researcher Martin Gibala. In that study (on which Little was a co-author), climbing three flights of stairs three separate times during the workday three times a week led to significant improvement in aerobic fitness after just six weeks.
The original goal of exercise snacks, whether in the form of stair climbing or other short bursts of intense activity, was to reduce the minimum time commitment needed to gain fitness. Since it took about 20 seconds, on average, to climb three flights of stairs, the weekly grand total was three minutes.
But the protocol has another potential advantage, Little and Gibala subsequently realized. Since it is spread throughout the day, it can break up long bouts of sitting and shake muscles out of their unhealthy dormant state.
The key point about prolonged sitting is that it’s more than just the absence of exercise. Little, a former collegiate track and cross-country runner, often still starts his day with an eight-kilometre run, so he’s easily exceeding the recommended weekly dose of 150 minutes of moderate to vigorous physical activity.
But once he sits down and starts plowing through those Zoom meetings, the muscles in his legs stop contracting, which means they need less energy and, over the course of just a few hours, become less sensitive to insulin. These and other metabolic effects can accumulate over time and raise the risk of insulin resistance and type 2 diabetes.
In the new study, Little and his colleagues recruited two groups of volunteers, one consisting of 12 adults with healthy weight and the other of 11 adults who were overweight or obese. They spent two nine-hour days sitting in the lab watching TV or working, and on one of the days they were asked to climb three flights of stairs once an hour.
In the overweight group, the results were clear: Total insulin levels over the course of the day were 16.5 per cent lower when they climbed the stairs. In the healthy weight group, the difference was slightly smaller and not statistically significant, but still suggestive.
So it’s reasonable to conclude that the protocol works, not just to enhance fitness, but to ward off the negative effects of sitting. But the bigger question is whether office workers are likely to hop up every hour and climb three flights of stairs.
“The short time commitment with exercise snacks is attractive,” Little says, “but I don’t think it’s just lack of time that’s preventing people from becoming active.”
The real barriers, he says, are complicated and vary from person to person. He’s collaborating with an expert in behaviour change to consider how to make the exercise-snack habit stick.
While there’s unlikely to be one eureka moment that unlocks exercise for everyone, snack-style protocols such as Little’s mini-stair workouts do remove more than just the time barrier. They don’t require advance planning, changing into workout clothes, getting up early or summoning motivation at the end of a long day. They don’t even require you to leave home.
In the current moment, with virtual meetings beckoning and many of the usual workout options unavailable, it seems like a good option to keep in mind.
Alex Hutchinson is the author of Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance. Follow him on Twitter @sweatscience.