KEEPING PACE: Several studies have confirmed the link between faster walking speeds and longer life, and a new analysis makes it possible to predict older adults' median life expectancy based on their pace.
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When an older friend or relative slows down people take notice—and often start to worry. Although walking pace is a seemingly basic measure to make, it has been gaining traction in the gerontology world as a reliable marker for overall health and longevity for those 65 and older.
A new analysis of walking speed studies shows that—down to the tenth of a meter per second—an older person's pace, along with their age and gender, can predict their life expectancy just as well as the complex battery of other health indicators.
So instead of a doctor assessing a patient's blood pressure, body mass index, chronic conditions, hospitalization and smoking history and use of mobility aids to estimate survival, a lab assistant could simply time the patient walking a few meters and predict just as accurately the person's likelihood of living five or 10 more years—as well as a median life expectancy.
And with the first wave of baby boomers hitting 65 this year, this easy measurement could become a powerful clinical tool that might help doctors decide on cancer screening, cardiac surgeries and other invasive treatments.
Walking—or gait—speed is "a powerful indicator of vitality," says Stephanie Studenski, a professor at the University of Pittsburgh's Division of Geriatric Medicine and co-author of the new analysis. "We just didn't use it in health care or public health."
With more people living longer, there is a growing disparity in older adults' health, "making it increasingly difficult to distinguish merely old (chronologically aged) from geriatric (biologically aged) patients," Matteo Cesari, of the Campus Bio-Medico University of Rome's Department of Geriatrics, wrote in an editorial accompanying the new study. For example, he noted, cancer patients who are "old" but not "geriatric" might be better candidates for more aggressive treatments, and similar distinctions could be helpful for cardiologists trying to make decisions about major surgeries for older patients.
The trick has been "being able to turn that gestalt into something that's measurable," Studenski says. "I think doctors even have this [viewpoint], but it's invisible in health care," she says, noting that walking speed is not usually described in medical records or other clinical notes. She hopes that her work will give walking speed "a more overt reality by measuring it."
The new analysis, published online January 4 in JAMA The Journal of the American Medical Association, found that walking speed turned out to be a consistent predictor of survival length across age, race and height categories, but it was especially useful in zeroing in on life expectancy for those who still live and get around independently and for those older than 75.
Despite its apparent variability in clogged grocery store aisles and busy sidewalks, individual "people have a remarkably stable preferred walking speed," Studenski notes. "Your body sort of self-selects your walking speed that best accommodates all of the systems that are needed to walk," she explains. And although walking might seem like a simple mode of locomotion, it is a biologically complex endeavor, she notes, which integrates the circulatory, respiratory, skeletal, muscular and nervous systems.
For the new paper Studenski and her colleagues analyzed nine cohort studies of community-dwelling adults 65 and older. Of the 34,485 adults in the studies, people with average life expectancy walked at about 0.8 meter per second. For those with a gait speed of one meter per second or faster "survival was longer than expected by age and sex alone," the researchers noted in their article.
But before people race out to time their paces, Studenski cautions, the test, although it is simple and requires no formal medical background, needs to be done in a controlled environment and executed by someone who has been trained to do it properly.
Even when done correctly, it is not a perfect measure. "Just like your blood pressure is one indicator of your health, it doesn't tell you everything—your walking speed doesn't either," Studenski says. If the correlation of walking speed with life expectancy—and possibly treatment decisions—gains prevalence in popular practice however, would people undergoing a walking test not be tempted to hedge their bets and pick up the pace? Studenski notes that those in the studies analyzed were not told the reason their pace was being measured. And like other health tests, "there's always a human element" that introduces some variability, she says, noting the example of "white coat hypertension" in which a person's blood pressure rises "because they're nervous that their doctor is measuring their blood pressure."
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14 Comments
Add CommentIt is an important finding. Through research investigations, a correlation between the walking speed and the probable life expectancy above 65 could be developed and remedial measures could be taken where possible. http://jdbapat.blogspot.com
Reply | Report Abuse | Link to this"white coat hypertension". I knew there was a name for it!! Every time that good looking nurse puts my hand under her arm and against her boob to take my blood pressure, she calls 911 !! When the doctor takes it, it shows 102/76. But I'm not complaining!!
Reply | Report Abuse | Link to thisAlternatively, 'residential communities' can determine who to stop feeding. Nothing personal - it's just business...
Reply | Report Abuse | Link to thisThis may be good news. Or it may simply be another instance of the correlation/causation connundrum. In other words, it's possible walking at the prescribed pace prolongs life. On the other hand, it's possible that increased lifespan and the tendency to walk at a faster rate of speed are both due to an as yet unknown or unrecognized latent variable. More research, please.
Reply | Report Abuse | Link to thisThat actually may be true. An injury or chronic condition that limits your stride or causes enough pain to reduce the time spent exercising may shorten your life. Get that operation if that's what it takes to keep you out of the vicious cycle of inactivity.
Reply | Report Abuse | Link to thisIt would be "a walk in the park" to monitor average walking speed over long periods of time for millions of people carrying cellphones with GPS-recievers. The phone companies knows the age and gender of the owner and the exact location of the phone at all times. The data could be anonymousised for integrity protection.
Reply | Report Abuse | Link to thisI believe that your assertion is probably correct. The author seems to lean this way as well. But as humans we have done this ourselves many times as morbid as it is. We assess who is at deaths door and then there is the old saying of 'spry old man'.
Reply | Report Abuse | Link to thisDoes the opposite applies ?. Working to improve your walking speed will increase your life expectancy.
Reply | Report Abuse | Link to thisIt's important to note the article is NOT saying higher walking speed causes you to live longer, it's just saying it's correlated with living longer. That said, studies have shown not exercising is as unhealthy as smoking, so all should do it. Still, diet and exercise can only help so much; we're fighting a loosing battle until we pursue a strategy of rejuvenation research, like the SENS Foundation is trying to do.
Reply | Report Abuse | Link to thisI walk with three different friends. One is faster, one is slower, and the other walks at about the same pace as I do. Before I read this article, I would have guessed that the one who walks the slowest would not live as long as the one who walks fastest—for a variety of reasons—but the one who walks at my same speed will live somewhere in between the two, just as I will. I don't think walking faster causes us to live longer as much as our walking speed predicts our general metabolic capacity and possibly, therefore, our longevity.
Reply | Report Abuse | Link to thisShould I wear skates, rollar blades, or use a skateboard after the age of seventy? How is this going to grant me longevity if I fall and injure myself to death in the process? Your article should include a disclaimer about providing advice that may cause injury if followed too exactly...by the imprudent and uninformed.
Reply | Report Abuse | Link to thisI agree with the author that walking speed of a person, if beng monitored over a period of time, could help doctor to investigate the condition of his health if the patient's pace slows down suddenly.
Reply | Report Abuse | Link to thisAn older friend who is much taller than me walks slower, and is quite insistent he will not walk quicker. This is not just down to slower gait but shorter stride, which may in turn be linked to circulation because muscles, ligaments etc (I guess) as well as oxygenation depend on good circulation for full function and maintenance.
Reply | Report Abuse | Link to thisWhat is important is to gauge the rate of recovery after falls and injuries that will cause an older person to slow down. Combined with many short breaks from sedentary behaviour, bandaging sprains, and exercising damaged backs while avoiding nasty twists and falls on slippery surfaces is key.
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