It's no surprise that people who walk their dogs tend to be more active overall than those who don't have pets.

But a group of researchers from the U.K. wanted to delve deeper into the connection between dog walking and health, especially as people age.

More than 3,000 adults participated in the study. They were asked whether they owned or regularly walked a dog. Participants were outfitted with a device to constantly measure their physical activity over a seven-day period. On average, people who owned dogs were sedentary for 30 minutes less per day than those who didn't have canine companions.

Because bad weather and the shorter days of winter are key reasons that many people don't stay active outdoors, the researchers linked the activity data to weather conditions and daylight hours.

They found that on shorter days, as well as on days that were colder and wetter, all study participants spent less time being active and more time just sitting. Dog walkers, however, were much less affected by those inclement weather conditions. They were much more likely to get outside even if the weather wasn't ideal. The study found that dog owners were 20 percent more active in bad weather than non-dog owners.

“We were amazed to find that dog walkers were on average more physically active and spent less time sitting on the coldest, wettest, and darkest days than non-dog owners were on long, sunny, and warm summer days," said project lead Andy Jones from University of East Anglia's Norwich School of Medicine.

Published in the Journal of Epidemiology and Community Health, the researchers used data from a study that is tracking the well-being of thousands of residents of the English county of Norfolk.

Neither snow nor rain nor heat nor gloom of night

"We know that physical activity levels decline as we age, but we’re less sure about the most effective things we can do to help people maintain their activity as they get older," said lead author Yu-Tzu Wu from the University of Cambridge.

“We found that dog walkers were much more physically active and spent less time sitting overall. We expected this, but when we looked at how the amount of physical activity participants undertook each day varied by weather conditions, we were really surprised at the size of the differences between those who walked dogs and the rest of the study participants.”

The researchers said that perhaps their findings could inspire the development of successful programs to motivate people to be active.

“Physical activity interventions typically try and support people to be active by focusing on the benefits to themselves, but dog walking is also driven by the needs of the animal," Jones points out. "Being driven by something other than our own needs might be a really potent motivator and we need to find ways of tapping into it when designing exercise interventions in the future.”

Mary Jo DiLonardo writes about everything from health to parenting — and anything that helps explain why her dog does what he does.

Dogs are the key to staying active as we age
People who walk their dogs tend to get more exercise as they get older, and that's especially true in winter.