Study details and key findings

For the study, the researchers analyzed data from 33,560 adults between the ages of 40 and 79 in the UK Biobank from 2013 and 2015. The average age of the participants was 62 and 97% were white.

The participants wore an accelerometer on their wrist for three to seven days to record their physical activity, including their step count and their distribution. Based on the accelerometer data, participants took fewer than 8,000 steps a day, with most taking fewer than 5,000.

The researchers divided the participants into four groups based on how they logged most of their daily steps: shorter than five minutes, five to less than 10 minutes, 10 to less than 15 minutes, and 15 minutes or longer. Of the participants, 42.9% were in the first category, with most of their steps occurring in short, under-five-minute walks.

After almost 10 years of follow-up, the researchers found that participants who regularly walked longer than 15 minutes were 80% less likely to die from any cause and almost 70% less likely to develop cardiovascular disease compared to those who got most of their steps in five minutes or less.

These benefits were also greatest for the least active individuals, or those who walked 5,000 steps or fewer a day. Among these participants, the risk of developing cardiovascular diseases dropped from 15% among short walkers (< five minutes) to 7% among those who walked for 15 minutes or longer. The risk of all-cause mortality also decreased from 5% (<5 minutes) to less than 1% (15+ minutes).

"You can start [walking] at any age; it's not too late," said Carmen Swain, director of the health and exercise science program at Ohio State University, who was not involved in the study. "The physiological adaptations that occur for a 20-year-old are also going to happen for a 60-year-old."

Regular exercise can also train your muscles to pull oxygen from your blood, which can then reduce heart rate, inflammation, and stress.

"Most people can walk for a minute or two or five without much issue. But when you start getting to … 20 and 30 and 40 and 60 minutes in, it becomes a lot harder for folks, and that's the capacity we're really trying to build," said Andrew Freeman, director of cardiovascular prevention and wellness at National Jewish Health.

For people who want to start walking regularly, health experts recommend starting slowly and adding a little more duration to your walks each time. Some ways to do this include parking your car a little farther away than you usually would or taking a stroll with friends.  

"Some is better than none, more is better than some," said Hannah Arem, an epidemiologist at MedStar Health Research Institute. "It's about an incremental increase over time and trying to find those longer bouts to have more health benefits."