Exercise is an important part of managing mental and physical health. It’s also a timesuck. But a longer workout isn’t always a better workout, and a new study reveals that you may not actually need to work out for as long as you think to reap fitness rewards.
Low-volume high-intensity interval training (HIIT), which includes no more than 15 minutes of high-intensity exercise with periods of rest breaking it up, can boost heart health and blood sugar control, according to a new review study.
There are several types of HIIT workouts, but the low-volume variety involves no more than a quarter of an hour of intense exercise. For example, a practitioner may jog for a couple of minutes, sprint for 30 seconds, then repeat several times.
A HIIT workout doesn’t have to include running; it can consist of exercises such as cycling, swimming, or bodyweight training. With warm-ups and rest periods included, most low-volume HIIT workouts last an average of 40 minutes, according to the review, which analyzed 11 studies on this type of exercise.
Don’t rush into HIIT all at once, warns Cordelia Carter, an orthopedic sports surgeon at New York University Langone Health. “This is about building endurance and strength long-term, and that means doing sessions only two or three days per week, with at least a day between them,” she told Runner’s World. “That allows you to incorporate the benefits—like more muscle mass and improved cardiorespiratory efficiency—more gradually.”
Compared to continuous aerobic exercise such as swimming laps, low-volume HIIT can lead to similar or even better improvements in cardiorespiratory fitness, blood sugar control, blood pressure, and heart function, Matthew Haines, a sports exercise specialist at the University of Huddersfield in the UK, wrote in The Conversation. This type of workout improves how the body burns fuel such as carbohydrates. It’s associated with better blood sugar control and may play a role in preventing type 2 diabetes. Low-volume HIIT also prepares the heart to pump out more blood with each heartbeat, a sign of improved functioning.
The Centers for Disease Control and Prevention recommends at least 150 minutes of moderate-intensity aerobic exercise or 75 minutes of vigorous-intensity aerobic activity each week. “We know 150 minutes each week sounds like a lot of time, but it’s not,” the CDC writes.
Try telling that to a parent of a newborn. Or anyone, really. Not having enough time is often the most commonly reported reason for not exercising. If that rings true with you, low-volume HIIT may be a good fit for keeping you fit during a time crunch.