There’s good news for people who struggle to get in the expert-recommended amount of exercise each week.
Recently, researchers have evaluated whether shorter versions of HIIT, or high-intensity interval training, that have as little as 4-min of high-intensity exercise in each session can also offer health benefits.
The review paper was published last month in the Journal of Physiology and announced Monday by The Physiological Society. The paper assembles 10 years of research on what’s called low-volume, high HIIT for health.
In December, the World Health Organization updated its exercise guidance, stating that 18 to 64-year-olds should strive to get “at least 150–300 minutes of moderate-intensity aerobic physical activity.”
If that can’t be done, the agency said to aim for “75–150 minutes of vigorous-intensity aerobic physical activity; or an equivalent combination of moderate- and vigorous-intensity activity throughout the week.”
“While the WHO guidelines may serve their purpose at a populational level, individualized and tailored low-volume HIIT interventions delivered by appropriately trained exercise professionals may be more effective at an individual level, especially for time-poor individuals,” said the study’s corresponding author, Dr. Angelo Sabag.
“This research is especially important now as people are looking for new and exciting ways to engage in regular exercise, after a year of lower physical activity due to the pandemic.”
WHO’s guidelines are greater than what’s recommended by the American Heart Association. It stated adults should aim for 150 minutes of moderate-intensity aerobic activity weekly or 75 minutes each week of vigorous aerobic activity. They can also aim for a combination of the two, spread out during the week. Still, it noted that adults can “gain even more benefits by being active at least 300 minutes (5 hours) per week.”
It was demonstrated in the new study that low-volume HIIT — which usually requires less than around 20 full minutes of physical activity including warm-up and cool down — produces similar gains to activities that meet the current guidelines. This is the case even though it requires drastically less time.
Researchers defined low-volume HIIT as spurts including less than 15 minutes of high-intensity exercise in each session.
The report found that this type of exercise can increase heart function and the health of arteries. Additionally, the research builds on the authors’ recent study that showed that as little as 4 minutes of HIIT done 3 times weekly for 12 weeks markedly improved blood sugar levels, liver fat, and cardiorespiratory fitness in adults with Type 2 diabetes.
Those interested in trying HIIT workouts should take care not to go full-speed ahead at once.
“The safer movements are going to be more bodyweight movements,” , Noam Tamir, founder and CEO of New York City’s TS Fitness told Self magazine.“When you add weight, technique is really important. If you’re going all-out and your form is off, you can put a lot of pressure on certain muscles and joints, which can lead to injury.”
