Frailty can look like slowing down, but doctors treat it as a serious warning sign.

A new trial published in PLOS ONE found older adults who walked at a fast pace were more likely to improve their frailty scores than those who walked at a leisurely pace, although both groups benefited.

Signs of frailty include a slow walking speed and taking longer on a “timed up-and-go test,” where a person stands up from a chair, walks a few paces, then returns to sit down. Taking more than about 13 seconds can be a possible marker of frailty.

Researchers believe exercise can help reverse the condition.

In the new study, Margaret Danilovich, a physical therapist and instructor at Northwestern University and an author of the paper, and her colleagues set up exercise groups in 14 retirement homes.

Research assistants assessed frailty before and after the intervention and coached participants through several months of weekly walking sessions in retirement community hallways.

Each group did similar walking tasks, including walking forward, backward, with walkers and without. Half walked casually, while the others were encouraged to walk much faster.

“We wanted to achieve a vigorous level of activity, more than 70 percent of the heart rate maximum,” Danilovich says. “There were standard scripts at certain timepoints throughout the walk.”

If participants slowed down, “the research assistant would give them verbal encouragement to walk faster.”

Danilovich says some people assume frail older adults should avoid doing too much.

“People tend to assume, ‘Someone is frail. We shouldn’t have them do too much,’” she says.

But, she says, “that’s a miscalculation,” and older people are capable of more than they might think.

The team found that people who kept their pace up saw greater improvements in frailty scores.

“Nearly 70 percent in the high-intensity walking group improved in at least one category, compared to 46 percent in the casual group,” Danilovich says.

Dr. Kenneth Rockwood, a professor of medicine at Dalhousie University in Canada who was not involved with the study, says more people dropped out of the high-intensity group than the casual group.

“The differential dropout makes it hard to generalize” how much the results apply to typical older people, he wrote in an email.

But he welcomed the research.

“Good on them for doing work to prevent frailty. We need a bunch more of that.”

The researchers found no baseline health differences between the groups.

Dr. Sara Espinoza, a geriatrician at Cedars-Sinai Medical Center in Los Angeles who was not involved in the research, says the findings are particularly interesting because they suggest high-intensity exercise can be safe for this group.

There was only one fall during the study.

Espinoza says putting the findings into practice may be difficult.

“The application of these findings or the translation to real life is sometimes difficult, because unfortunately our healthcare system does not reimburse/pay for this type of exercise training,” she wrote in an email.

“We can order PT [physical therapy], but it is generally not high-intensity exercise that is going to increase the heart rate.”

The researchers hope to extend their work to healthy older people who wear smart watches, to better understand how to prompt walkers to go faster.

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