Women saw cardiovascular improvements with just three 10-minute workouts a week.
Fitting in workouts can be tough. That’s why a new study from McMaster University in Canada is such good news: Researchers found that exercise bursts as brief as 20 seconds—like sprinting up a few flight of stairs—can have major heart health benefits.
Stair climbing can be done pretty much any time and anywhere, the researchers say, giving busy people one less excuse for skipping workouts altogether. Previous research has shown that longer, sustained step workouts can improve heart health, but this is the first time scientists have studied the effects of sprint intervals—shorter bursts of vigorous activity followed by short recovery periods—in the context of stair climbing.
Researchers recruited 31 sedentary but otherwise healthy women for a series of experiments, and assigned them to different exercise routines involving either a stationary bike or a local stairwell. All of the workouts required a total commitment of 10 minutes, including warm-up and cool-down.
For one workout, women warmed up by walking on flat ground at a brisk pace for two minutes, then completed three 20-second “all-out” bursts of effort, climbing one step at a time as quickly and safely as possible. Each 20-second burst was interspersed with a two-minute recovery period (walking back down and on flat ground at a slower pace), and a three-minute cool-down at the end.
Another group of women did a slightly different workout on a shorter set of stairs, warming up for two minutes and then completing three 60-second vigorous bursts up and down the stairs, with one minute recovery in between and three minutes of cool down at the end. (In this case, they were told that vigorous meant relatively intense, but not all-out.)
The second workout was designed so that people could easily replicate the workout in homes or workplaces with at least one set of stairs, say the authors. The workouts were completed three times a week for a total of six weeks, and the women were tested for measures such as heart rates, blood pressure, and oxygen uptake at both the start and end of the study.
It turns out that both stair workouts improved cardiorespiratory fitness: The regimen involving 20-second all-out bouts improved the women’s VO2max—a measure of how efficiently the body takes up and uses oxygen—by 12 percent over six weeks, while the regimen with 60-second vigorous intervals improved VO2max by 8%. In terms of cardiovascular health, the authors say, a 12 percent VO2max improvement is comparable to losing 7 centimeters from one’s waist circumference or lowering one’s systolic blood pressure by 5 points.
These results were also comparable to results from women who did similar a similar workout on an exercise bike, suggesting that stairs can be just as effective at boosting fitness as expensive exercise equipment. The findings were published in the journal Medicine and Science in Sports and Exercise.
Yes, in a perfect world, we’d all be spending much more than 30 minutes a week getting our heart rates up—not to mention stretching and strength training, too. And, to be fair, these super-quick workouts certainly aren’t a cure-all: Measures of insulin sensitivity (a risk factor for diabetes) didn’t change over the six weeks of the study, for example, and changes in body composition were minor to non-existent.
But the research suggests that as little as 10 minutes of exercise a day, three days a week—and as little as 60 seconds of vigorous activity per session—can make real improvements in heart health. And with less than 15 percent of North American adults currently meeting recommended physical activity guidelines, the authors say, that’s important.
"Interval training offers a convenient way to fit exercise into your life, rather than having to structure your life around exercise," said lead author Martin Gibala, PhD, a professor of kinesiology at McMaster University, in a press release. "Stair climbing is a form of exercise anyone can do in their own home, after work or during the lunch hour."