Updated on January 11, 2023.
Don't have time for regular 60-minute walks? No problem. Research shows that shorter walks with periods of higher-intensity movement mixed in—an approach to exercise known as interval training—can garner even greater health benefits than longer, lighter-intensity ones.
Picking up the pace
In a 2019 article in Mayo Clinic Proceedings, researchers found that for people in middle age and older, a five-month interval walking training program increased peak aerobic activity and decreased the likelihood of lifestyle-related diseases such as diabetes, heart disease, and obesity.
Intervals can also be good for younger adults. In a 2017 study in Health and Quality of Life Outcomes, researchers looked at 48 obese college students ages 18 to 26. The participants took part in a treadmill training program, exercising 60 minutes a day, three days a week for 12 weeks. After three months, people who did higher- and medium-intensity walking regimens had considerably higher reductions in body mass index, weight, waist circumference, body fat percentage, and fat mass than those in the lighter-intensity group.
Intervals for chronic conditions
The benefits may even extend to folks managing chronic conditions. A 2018 study in Arthritis Research & Therapy focused on interval training in adults with rheumatoid arthritis (RA). Researchers found that a high-intensity interval walking program did not change participants’ body composition greatly, but it increased cardiorespiratory fitness by 9 percent, decreased resting blood pressure and heart rate, and reduced RA symptoms by 38 percent. (Cardiorespiratory fitness is a measure of how well the heart and lungs supply oxygen to the body.) The participants undertook three 30-minute exercise sessions a week for 10 weeks.
Why a little burst of effort can mean a lot
It’s not known exactly why interval walking (and other kinds of interval training) may be better for you than longer, slower workouts. But there are a few theories.
During a workout, stimulating your muscles leads to a process that makes mitochondria work more effectively. Mitochondria are parts of human cells that are important for boosting metabolism. Their action may also play a role in reducing your risk of high blood sugar and obesity.
Another possibility is that increased activity for short periods helps open the large blood vessels of the heart, reducing the risk of coronary artery disease. Researchers have also found that interval training can help lower your heart rate after training. A high heart rate—even without other risk factors—is a predictor of sickness and death from cardiovascular disease.
Higher-intensity exercise has been shown to be more effective than lower-intensity activity in improving body composition and reducing fat—particularly around the abdomen, where fat buildup can be particularly dangerous.
Intervals 101
Doing interval training can be a little trickier to figure out than other exercise regimens (like getting 150 weekly minutes of moderate-intensity exercise at a steady pace). But there are several ways to make sure you are increasing your rhythm the right amount.
Generally, high-intensity exercise involves working at a pace that is 70 percent to 85 percent of your maximum heart rate. Lower intensity is 50 percent to 70 percent of that maximum. You can figure out your maximum heart rate by subtracting your age from 220. That would be about 180 beats per minute for an average 40-year-old person, and 85 percent of that would be about 153 beats per minute.
A wearable fitness tracker can also help you determine your heart rate. If you don’t have one, you can count your pulse at your wrist for 30 seconds and double that number to get your beats per minute.
If you aren’t a math major, try this simpler (though less-precise) talk test: During a moderate-intensity workout, you should be able to talk but not sing. During a high-intensity period, you should only be able to say a few words without pausing to catch your breath.
In much of the research on interval walking, participants walked a total of 30 minutes to an hour at least three times a week. Interval work can range from alternating between low- and high-intensity periods of one minute each to longer intervals of up to four minutes. The idea is that you push yourself during the intervals, then give our body (and breath) a chance to catch up while you walk during the slower periods.
A variety of interval workout plans can be found online, or you can talk to your healthcare provider or a personal trainer to determine a walking regimen to fit your needs, goals, and fitness level.
