Of course, there’s a caveat: To get results from such short workouts, you have to be willing to push yourself hard, Gillen says. Numerous studies have shown that high-intensity interval training protocols can yield results from relatively short workouts. Gillen and her colleagues at McMaster University wanted to know how short that training could be.
The answer, from a study they did in 2016, was: three times a week, intense exercise for one minute in a total workout of 10 minutes (including warm-up and cool-down).
Even a little exercise can mean big improvements in your health
Gillen’s team randomly divided participants into three groups. Three times a week they pedaled an exercise bike for 45 minutes with moderate effort. A second group did the 10-minute workouts that included three 20-second segments of all-out sprint cycling three times a week, for a total of one minute of high-intensity exercise per workout. (The rest of the time it was easy turning.) A third group acted as a control and did nothing.
After 12 weeks, both exercise groups had improved their insulin resistance and fitness (as measured by their ability to use oxygen during exercise) by about 19 percent. The gains were similar between the groups, although the group doing short workouts at high-intensity intervals spent only about 22 percent as much on exercise as the group doing traditional longer workouts.
Similarly, a 2020 study by researchers at University Hospital Erlangen in Germany put 65 sedentary, obese volunteers on an exercise program that consisted of warming up on a stationary bike for two minutes and then five one-minute bouts at 80 to 95 percent of their maximum heart rate, with one minute recovery periods in between. With the three minute cool down, the total exercise time was 14 minutes and these workouts were performed twice a week for 12 weeks. Participants in this simple 28-minute-a-week program improved their VO2max scores (a measure of cardiovascular fitness), and they also reduced their blood pressure and waist circumference.
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The improvements in cardiorespiratory fitness seen in these studies are a strong predictor of reduced morbidity and mortality risk, and are especially important for people at risk of developing diabetes or other metabolic disorders, said Louise de Lannoy, an exercise physiologist at the Children’s Hospital of Eastern Ontario Research Institute.
Still, the intensity required to achieve the benefits of short workouts takes some diligence.
“Especially for someone who has led a sedentary life, it can be quite a challenge to make that maximum effort,” says de Lannoy. This level of intensity feels all the way — you’re going as hard as you can. “But it can also be fun. It’s fast, a bit of pain, you rest and do it again,” says de Lannoy.
Another 2020 study confirmed that some people like these hard interval training programs enough to keep going. Sports scientist Matthew Stork of the University of British Columbia and his colleagues brought a group of previously sedentary adults into the lab to do short workouts at one-minute intervals on an exercise bike. Participants reported that the high-intensity attacks were difficult, but some of them enjoyed them enough that they continued to do them after the study.
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“I’ve tried these workouts myself, and it takes a lot of self-coaching to get to 90 percent of your max,” says de Lannoy. That said, if you do a workout with repeated hard intervals and a short rest, they will likely get harder as you progress, so even if your first interval is only 60 percent of your max, by the third or fourth you might be closer to 90. percent, she says. If you don’t have a stationary bike, brisk walking up stairs is another great way to get your heart rate up quickly.
“A good rule of thumb is to build over time,” says de Lannoy. “You could start with 60 to 70 percent of your maximum heart rate, and try to increase that over time and build up to 90 percent.”
Short workouts can build muscle
Cardio workouts aren’t the only ones getting shorter. Studies also show that you can achieve great strength gains with short resistance workouts.
A 2019 study published in the journal Medicine & Science in Sports & Exercise examined the correlation between the number of sets of exercises performed and strength gains.
Study participants did a similar routine of seven strength-training exercises three times a week. One group did five sets of the exercise each session, another group did three sets, and the third group only did one set of exercises per workout. By the end of the eight-week program, all groups had achieved similar improvements in muscle strength and endurance. By doing three or five sets per workout, people took more time exercising, but it didn’t result in greater gains. (However, the group that did the longer workouts made greater increases in muscle size in the thigh muscles and elbow flexors.)
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There is often skepticism about the idea of short workouts because they have been portrayed as gimmicky, says James Steele, an associate professor of sports and exercise sciences at Solent University in England and principal investigator at the London-based UKActive Research Institute. But he says that if you want to get stronger, you don’t necessarily have to spend a lot of time in the gym or do a lot of reps. Instead, it’s important to do the exercise until you reach “momentary muscle failure” — the point where you can’t complete another rep. Steele was part of a research team that published evidence-based resistance training recommendations calling for a single set of eight to 12 repetitions for transient muscle failuree.
Dutch company Fit20 runs franchise fitness studios that specialize in this “minimum effective dose” approach to workouts. It has a dataset of nearly 15,000 people who participated in their program over a seven-year period, and Steele’s team recently used it to model people’s strength development over time. The team found that Fit20 members saw significant strength gains (on the order of 30 to 50 percent gains in the first year) despite a minimal amount of training: a single set of four to six repetitions of six exercises, once a week.
The study shows that you can make significant improvements in muscle strength with just one short workout per week, but Steele says he recommends people aim for twice a week so that if they miss a session, they stay on track.
The minimal effective dose approach is not just for average people. Studies conducted by Patroklos Androulakis-Korakakis, a researcher at Solent University and a coach at StrongerByScience.com, a program that provides science-backed strength training, show that it also works for highly skilled athletes. He researched serious powerlifters and found that they also achieve significant strength gains while on a minimally effective dosing plan.
Remarkably, the powerlifters in the Androulakis-Korakakis studies who trained with a minimal-dose approach ultimately experienced very little pain. “They had very low pain scores, one or less on a scale of one to five,” he says.
Androulakis-Korakakis says his research suggests that “Hey, you could do a lot less than you currently do and see great results.” A minimalist approach may not give the absolute best results, but it’s a lot more bang for your buck, especially when you consider the trade-off between time and recovery, he says.
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Switching to shorter workouts isn’t just a way to save time. It can also help you stay fit even when life gets in your way.
“Say you have exams or your work starts to pile up and you only have a few hours a week” to exercise, says Androulakis-Korakakis. Rather than feeling like your strength and muscle mass will suffer, a minimal dose approach can help you build your fitness.
“It’s hard to say you don’t have 10 or 15 minutes to find. That’s just not checking your email again or getting off social media,” says de Lannoy.