Walking and All-Cause Mortality

[Dean Pomerleau]

This new study [1] in JAMA found that walking 8000 steps per day was associated with a ~50% reduction in all-cause mortality relative to 4000 steps per day. Boosting steps to 12,000 per day appeared to be even better. It was associated with a 65% reduction in all-cause mortality.

Linearly extrapolating to 45,000 steps per day (~20 miles - you were close Drew!) would equate to about a 168% reduction in all-cause mortality. 😉

Interestingly, walking intensity (i.e. steps per minute) didn't seem to matter much at all.

-Dean

-----------

[1] JAMA. 2020;323(12):1151–1160. doi:10.1001/jama.2020.1382

Association of Daily Step Count and Step Intensity With Mortality Among US Adults. 

Saint-Maurice PF, Troiano RP, Bassett DR, et al.

Abstract
Importance  It is unclear whether the number of steps per day and the intensity of stepping are associated with lower mortality.

Objective  Describe the dose-response relationship between step count and intensity and mortality.

Design, Setting, and Participants  Representative sample of US adults aged at least 40 years in the National Health and Nutrition Examination Survey who wore an accelerometer for up to 7 days ( from 2003-2006). Mortality was ascertained through December 2015.

Exposures  Accelerometer-measured number of steps per day and 3 step intensity measures (extended bout cadence, peak 30-minute cadence, and peak 1-minute cadence [steps/min]). Accelerometer data were based on measurements obtained during a 7-day period at baseline.

Main Outcomes and Measures  The primary outcome was all-cause mortality. Secondary outcomes were cardiovascular disease (CVD) and cancer mortality. Hazard ratios (HRs), mortality rates, and 95% CIs were estimated using cubic splines and quartile classifications adjusting for age; sex; race/ethnicity; education; diet; smoking status; body mass index; self-reported health; mobility limitations; and diagnoses of diabetes, stroke, heart disease, heart failure, cancer, chronic bronchitis, and emphysema.

Results  A total of 4840 participants (mean age, 56.8 years; 2435 [54%] women; 1732 [36%] individuals with obesity) wore accelerometers for a mean of 5.7 days for a mean of 14.4 hours per day. The mean number of steps per day was 9124. There were 1165 deaths over a mean 10.1 years of follow-up, including 406 CVD and 283 cancer deaths. The unadjusted incidence density for all-cause mortality was 76.7 per 1000 person-years (419 deaths) for the 655 individuals who took less than 4000 steps per day; 21.4 per 1000 person-years (488 deaths) for the 1727 individuals who took 4000 to 7999 steps per day; 6.9 per 1000 person-years (176 deaths) for the 1539 individuals who took 8000 to 11 999 steps per day; and 4.8 per 1000 person-years (82 deaths) for the 919 individuals who took at least 12 000 steps per day. Compared with taking 4000 steps per day, taking 8000 steps per day was associated with significantly lower all-cause mortality (HR, 0.49 [95% CI, 0.44-0.55]), as was taking 12 000 steps per day (HR, 0.35 [95% CI, 0.28-0.45]). Unadjusted incidence density for all-cause mortality by peak 30 cadence was 32.9 per 1000 person-years (406 deaths) for the 1080 individuals who took 18.5 to 56.0 steps per minute; 12.6 per 1000 person-years (207 deaths) for the 1153 individuals who took 56.1 to 69.2 steps per minute; 6.8 per 1000 person-years (124 deaths) for the 1074 individuals who took 69.3 to 82.8 steps per minute; and 5.3 per 1000 person-years (108 deaths) for the 1037 individuals who took 82.9 to 149.5 steps per minute. Greater step intensity was not significantly associated with lower mortality after adjustment for total steps per day (eg, highest vs lowest quartile of peak 30 cadence: HR, 0.90 [95% CI, 0.65-1.27]; P value for trend = .34).

Conclusions and Relevance  Based on a representative sample of US adults, a greater number of daily steps was significantly associated with lower all-cause mortality. There was no significant association between step intensity and mortality after adjusting for total steps per day.

 Full Text

[drewab]

Glad to see walking seems to make such a difference! It would be fascinating to see what would happen if they had additional groups at 16,000, 20,000, and so forth. Dean, is your current step count still that high? I believe you had backed off for a while due to knee discomfort or something along those lines. Did you resume that exercise regime?

It's encouraging that step intensity didn't appear to matter. This is great news for people who cannot, for a variety of reasons, move at a brisker pace. 

[elatedsquirrel]

Is it possible that the healthier people were more able to walk more?

[Dean Pomerleau]

9 hours ago, drewab said:

Dean, is your current step count still that high? I believe you had backed off for a while due to knee discomfort or something along those lines. Did you resume that exercise regime?

Yes I'm still walking that much. I think you may be confusing me with Tom. 

 

3 hours ago, elatedsquirrel said:

Is it possible that the healthier people were more able to walk more?

Welcome Elated!

Good point. But from the full text of the study, those very favorable hazard ratios for 8k and 12k steps per day relative to 4k were after controlling for the following potentially confounding factors in the researcher's Model 3:

Model 3: [sex, age] + diet quality, race/ethnicity, body mass index, education, alcohol consumption, smoking status, diabetes, stroke, coronary heart disease, heart failure, cancer, chronic bronchitis, emphysema, mobility limitation, and self-reported general health.

Her is the relevant table from the paper:

This implies to me that reverse causality can't much of a factor contributing to the apparent benefits of more walking. 

--Dean 

[elatedsquirrel]

Great. I'll get walking then! 😀

[TomBAvoider]

Regarding problems with exercise, the latest for me is - feet. I read an excellent book by an editor about her old age (Diana Athill "Somewhere Towards the End: A memoir") - she lived to 101 - and one remark she made I found of particular interest: she said that the cushioning in the feet erodes with age and so it becomes painful to stand, walk, etc. because the bones are too close to the skin, and this happens with age. At the time (a few years ago) I didn't have the problem, but these days I do. 

For example, for a couple of months how, I've taken to doing squats 4 times a week. Each session is 21 minutes, and I do some 650 squats in each session. I find no problem for my muscles at all doing squats - what I do find a serious problem is my feet hurt while in the same position for that long, actually they start hurting around minute 10 or so. This despite wearing trainers with good cushioning. I intend to incorporate a mat and see if it helps. When I jog along the streets these days (used to do it on an athletic track that was cushioned), the balls of my feet hurt, despite my running shoes being quite new. Walking - again, after awhile, the bottoms of my feet are in pain due to seemingly not enough cushioning in my feet. I had no such problems a few years ago, it all started maybe 2 years ago.

Thus, many of us have all sorts of limitations we have to work around, or take measures. I like walking, but I'll have to figure out a better way to ameliorate my feet issues.

[KHashmi316]

I do almost NO walking these days except in the grocery/supply store. 

Prior to 2009, I used to put in 5-6 miles worth of steps daily. And my CR'd joints and (especially) feet suffered. Also, walking burns a LOT of calories. Not an easy economy on heavy CR. Indeed, I felt quite drained and exhausted after my daily walks.

Since 2009, I do bicycle regularly -- every other day (~7-10 miles), at a leisurely pace of 9-10 mph. On opposite days, I use an indoor (stationary) recumbent bike,  leisurely pace, ~20 min.

One very important part of my exercise routine is multitasking with a media player (phone or iPod), using earphones, playing mostly music. I used to do audio-books and downloaded podcasts, especially in the "walking days". But concentrating on audio-books or podcasts --while all the other muscle memory (of walking) is active -- often made me "tune out". I guess I can kinda see where the "walk and chew gum" cliche came from.

Music + exercise is much more ideal IME. It is a kind of "meditative" time where the mind can drift randomly for a bit. Ideas, thoughts, reflections on current events or what I may have read or watched on YouTube, bounce around in the "exercising  brain" in all sorts of novel  and amusing ways. HOWEVER, on heavy CR, even music seemed dull and and lifeless near the end of  a typical walk (energy depleted, running on fumes, low body fat and low blood-sugar levels, I assume).

Cycling-only for exercise, grocery getting, etc., changed everything. But all my podcasts and audio-book (non-music files) listening is at home. 

Music + biking is hugely enjoyable:... and that is a rare and appreciated phenomenon in the emotionally-buffered mind of a hard--core CR individual.

BTW: One thing I have NEVER been able to do is jog or run. That VO2 max test for the WUSTL CR study was pretty much the only time since high-school gym class that I entered jogging/running mode. 

[TomBAvoider]

I agree wrt. listening to something while exercising - I'm a big believer in it, at least partially because I don't enjoy the exercise itself. Listening to something makes the time pass almost unnoticed. Personally, I don't listen to music, but rather I attempt to learn something - so I listen to lectures, language courses and certain podcasts. You'd think that exercising would interefere with the process of learning, but apparently there's a paradox - research shows that you absorb information better when you're in different/changing environments, so such as running or walking are ideal. 

I too bike, but not for exercise, it's strictly leisure - and I don't do too much of it. As exercise, I'm worried about biking apparently not doing much for bones, plus the tricky problem of prostate cancer - my genetic profile (according to 23 and me) says my odds of PC are elevated, so as a precaution I try to minimize risks (although anything from genetic samples like these should be taken with a boulder of salt!). Still, it's apparently true that PC risk is elevated by the biking seat pressure /shrug/.

Jogging/running for me works, because so many systems are involved, including the jarring of bones (although that does NOT apply to the upper body!). I find jogging to be quite versatile - for example, I often experiment with my stride, foot strike, how deep I bend my knees and so on - I feel that adopting a variety of styles is more beneficial than just constantly only jogging exactly the same way - plus it has the same advantage as Dean's salad variety: I don't have to worry that there's some small/large imperfection in my running form and I'm doing damage by piling on hours and hours of faulty form running.  

Anyway, my main worry wrt. exercise is making sure that I don't overdo it. I have a tendency to overdo things like this (diet, hobbies, interests, etc., etc., etc.), so I really have to watch myself. It's critical to allow for recovery time - and besides, I resent the time sink - my ideal scenario would be to spend the minimum time I need to obtain health benefits and I don't want to expend 99% more effort for 1% more benefit. That's how I see this whole "walking" exercise - I already jog, and do some basic muscle or anaerobic exercise - how much more am I buying health/longevity-wise by piling on hours of walking? I think I'll skip the "walking as exercise" - I do some basic walking around the neighborhood and that'll have to do as far as "walking", even if it doesn't qualify as exercise. YMMV.

[Ron Put]

This seems to jive with last year's study which found:

"Researchers found that older women who took 4,400 steps a day had a lower risk of dying than those taking 2,700 steps a day.

Death rates declined with more steps taken each day until about 7,500 steps a day, when the benefit leveled off."

Of course, it's a bit of a "chicken or egg" question, as it may simply mean that people who are healthy are more mobile during their day, while people with health conditions, such as CVD or obesity, are simply unable to walk as much. 

The 2019 study mentions that "The design of the study couldn’t rule out the possibility that the women’s stepping patterns were affected by other health factors that also influenced mortality—although the researchers did adjust for many of these."

Based on my fitness trackers over the years I seem to be right around the 7-8000 mark on most days, just walking around the house.  But maybe four days a week I go for a hike (I run uphill for portions to get my heart rate above 150-160 for a few minutes) which adds another 6-7000 steps.  On those days, it's actually quite challenging to consume all the calories I need, according to Cronometer and my current tracker, Fitbit Versa.

[KHashmi316]

17 hours ago, Ron Put said:

Of course, it's a bit of a "chicken or egg" question, as it may simply mean that people who are healthy are more mobile during their day, while people with health conditions, such as CVD or obesity, are simply unable to walk as much. 

And ultra health nuts and marathoners, with superb lifelong habits,  can walk (and do) THAT MANY steps.

But it's JAMA for Chrissake!! They're supposed to correct for variable and correlations..... PFFFFFFFFFT.

 ;) ;) ;)

[tea]

On 5/8/2020 at 1:18 PM, TomBAvoider said:

Regarding problems with exercise, the latest for me is - feet. I read an excellent book by an editor about her old age (Diana Athill "Somewhere Towards the End: A memoir") - she lived to 101 - and one remark she made I found of particular interest: she said that the cushioning in the feet erodes with age and so it becomes painful to stand, walk, etc. because the bones are too close to the skin, and this happens with age. At the time (a few years ago) I didn't have the problem, but these days I do. 

For example, for a couple of months how, I've taken to doing squats 4 times a week. Each session is 21 minutes, and I do some 650 squats in each session. I find no problem for my muscles at all doing squats - what I do find a serious problem is my feet hurt while in the same position for that long, actually they start hurting around minute 10 or so. This despite wearing trainers with good cushioning. I intend to incorporate a mat and see if it helps. When I jog along the streets these days (used to do it on an athletic track that was cushioned), the balls of my feet hurt, despite my running shoes being quite new. Walking - again, after awhile, the bottoms of my feet are in pain due to seemingly not enough cushioning in my feet. I had no such problems a few years ago, it all started maybe 2 years ago.

Thus, many of us have all sorts of limitations we have to work around, or take measures. I like walking, but I'll have to figure out a better way to ameliorate my feet issues.

i imagine that cushioning in the feet is mostly muscle, it doesn't seem to me like there is much subcutaneous fat to speak of. I am younger ,but at least for me, I had developed foot pain (morton's neuroma) and found myself with sore feet quite often after walking/standing. I made the switch to "minimalist shoes" some time ago and have subsequently been pain free, even after walking as much as 15 miles in a day. I think strengthening the muscles/connective tissues in the foot is helpful, and using highly cushioned/arched shoes prevents some of the natural adaptations that might otherwise toughen up your feet.

another thing worth mentioning. i'm not sure what your trainers are, but true "weightlifting shoes" are flat, little cushioning, and no heel. for curiosity's sake you could try switching to barefoot or socks on a soft surface or mat and see if that helps.

[Dean Pomerleau]

On 5/9/2020 at 1:05 PM, KHashmi316 said:

But it's JAMA for Chrissake!! They're supposed to correct for variable and correlations..... PFFFFFFFFFT.

😉 😉 😉

Khurram, 

You don't seem to be reading very carefully. 

On 5/8/2020 at 6:09 AM, Dean Pomerleau said:

But from the full text of the study, those very favorable hazard ratios for 8k and 12k steps per day relative to 4k were after controlling for the following potentially confounding factors in the researcher's Model 3:

Model 3: [sex, age] + diet quality, race/ethnicity, body mass index, education, alcohol consumption, smoking status, diabetes, stroke, coronary heart disease, heart failure, cancer, chronic bronchitis, emphysema, mobility limitation, and self-reported general health.

--Dean 

[KHashmi317]

Years ago, after watching a doc on African persistent hunters (who regularly pursue prey animals for days, and, hence put in a lotta steps), I did a little digging and came up with little wrt longevity benefits. 

Careful folks! Human appetite psychology is very sneaky ... often trying trying to find back doors into snarfville. And more calories you burn, the more powerful those drives amass.

REFS:

https://en.wikipedia.org/wiki/Persistence_hunting

https://en.wikipedia.org/wiki/Endurance_running_hypothesis

[KHashmi317]

A few more thoughts ....

In a "natural CR" state (famine), organisms would be putting in more steps to look for (and/or pursue) food. 

So maybe, there is an built-in Fitbit of a sort, "bean counting". And it's a DUMB counter. So it ignores modern-man attributes (overweight, excess calories,  DELIBERATE calorie restriction). So the counted steps may put the organism into a CR-like mortality sequence. 

[Ron Put]

On 5/11/2020 at 7:03 AM, KHashmi317 said:

... So maybe, there is an built-in Fitbit of a sort, "bean counting". And it's a DUMB counter. So it ignores modern-man attributes (overweight, excess calories,  DELIBERATE calorie restriction). So the counted steps may put the organism into a CR-like mortality sequence. 

This is an interesting thought.

I am not sure I'd necessarily connect it to CR, but there might really be a pattern. 

See this:

Early Epigenetic Changes Regulate Voluntary Exercise in Mice: Study

Every man, woman, and mouse partakes in a different amount of voluntary physical activity. Some willingly run miles a day with no destination in mind, while others walk only when they need to get somewhere. Differences in how much physical activity mice choose to engage in is influenced by epigenetic changes in early development, according to a study published in Nature Communications on December 2.  

“The study clearly shows that voluntary exercise behavior is sensitive to epigenetic influences, which is significant because, as the authors point out, it implies that there is a critical period in childhood where a ‘set point’ for exercise behavior is established, ...”

 

[KHashmi317]

4 hours ago, Ron Put said:

I am not sure I'd necessarily connect it to CR, but there might really be a pattern. 
 

I should be more clear, if that's even possible when armchair hypothesizing.

I call it a "famine conspiracy". It's a blanket term I came up with that serves as parent explanation of, e.g., why cancer, pathogens, headaches, allergies "leave us alone" when BF levels get (and stay) low. (See my other post on this elsewhere). When the famine danger -- which is SUBSTANTIAL -- is over, and BF returns to normal, cancer and pathogens can resume normal biz (of evolving and/or thinning out) the herd. 

But the internal tracking software might not be that sophisticated ... so lotta steps may be = to "famine".

[Ron Put]

18 hours ago, KHashmi317 said:

I should be more clear, if that's even possible when armchair hypothesizing.

I call it a "famine conspiracy". It's a blanket term I came up with that serves as parent explanation of, e.g., why cancer, pathogens, headaches, allergies "leave us alone" when BF levels get (and stay) low. (See my other post on this elsewhere). When the famine danger -- which is SUBSTANTIAL -- is over, and BF returns to normal, cancer and pathogens can resume normal biz (of evolving and/or thinning out) the herd. 

But the internal tracking software might not be that sophisticated ... so lotta steps may be = to "famine".

OK, it actually makes sense to me.  I haven't found a study which explores this, but there should be one.

[Clinton]

On 5/10/2020 at 9:11 PM, DHL said:

And a corollary to this research is that people that eat regularly tend to live longer.

Currently scientists are researching if regular breathing promotes longevity, but the jury is still out. 

Fascinating!!

Edited May 14, 2020 by Clinton

[Mike41]

On 5/11/2020 at 10:03 AM, KHashmi317 said:

A few more thoughts ....

In a "natural CR" state (famine), organisms would be putting in more steps to look for (and/or pursue) food. 

So maybe, there is an built-in Fitbit of a sort, "bean counting". And it's a DUMB counter. So it ignores modern-man attributes (overweight, excess calories,  DELIBERATE calorie restriction). So the counted steps may put the organism into a CR-like mortality sequence. 

Interesting concept. So it may be that the two factors coincide. Cr and exercise. Therefore heavy people can counteract the effects by walking. It may be that crd folks won’t benefit from so much walking then or not as much as an overweight person would. Pure speculation but seems reasonable. This seems even more plausible when you consider the fact that in this study Intensity did not matter one way or the other! Think about that.

Edited May 15, 2020 by Mike41

[Dean Pomerleau]

Al posted this study [1] (thanks Al!) that also found a continuous decrease in mortality during follow-up with increasing numbers of steps per day up to ~15K for people in their late-50's.

But by far the biggest bang for the buck (50% mortality reduction) came from the jump from first quartile(~4600 steps per day) to the second quartile (~6900 steps per day). Beyond around 7K steps per day the survival gains were more modest. Here is the graph of steps per day vs. mortality:

They threw out deaths that occurred in the first two years after enrollment (to exclude people who couldn't walk because they were already pretty sick) and they statistically adjusted for the following potential confounders:

Sex, [step-counter] wear time, [Vigorous Physical Exercise - i.e. exercise beyond walking], education, body mass index, smoking (never/former/current), alcohol intake, and number of [self-reported] medical conditions, excluding deaths within first 2 years (n=9)

--Dean

-----

[1] Step by Step: Association of Device-Measured Daily Steps With All Cause-Mortality - a Prospective Cohort Study.
Hansen BH, Dalene KE, Ekelund U, Fagerland MW, Kolle E, Steene-Johannessen J, Tarp J, Anderssen SA.
Scand J Med Sci Sports. 2020 May 19. doi: 10.1111/sms.13726. Online ahead of print.
PMID: 32427398
Abstract
Introduction: Walking is free, does not require special training, and can be done almost everywhere. Therefore, walking is a feasible behavior on which to tailor public health messages. This study assess the prospective association and dose-response relationship between daily steps and all-cause mortality.
Materials and methods: Daily steps were measured by waist-mounted accelerometers in 2,183 individuals (53% women) for seven consecutive days at baseline (2008-09). Participants were followed for a median period of 9.1 years and associations between steps and all-cause mortality determined by registry linkage were assessed using Cox proportional hazard regression with adjustment for relevant covariates.
Results: Mean age was 57.0 (SD 10.9) years at baseline. Median (IQR) daily steps across ascending quartiles were 4651 (3495-5325), 6862 (6388-7350), 8670 (8215-9186), and 11467 (10556-13110), respectively. During follow-up, 119 individuals died (68% men). Higher number of daily steps was associated with a lower risk of all-cause mortality with hazard ratios of 1.00 (referent), 0.52 (0.29-0.93), 0.50 (0.27-0.94), and 0.43 (0.21-0.88) across ascending quartiles of daily steps in the multivariable-adjusted model with follow-up commencing two years after baseline. Risk differences per 1000 individuals for ascending quartiles were 6.8 (2.9-9.3), 7.1 (0.8-11.1), and 8.0 (1.7-12.1), respectively.
Conclusions: Daily steps were associated with lower mortality risk in a non-linear dose-response pattern. The risk is almost halved when comparing the least active referent against the second quartile equivalent to a difference of about 2200 daily steps. Encouraging those least active to increase their daily steps may have substantial public health implications.
Keywords: Steps; all-cause mortality; device-measured; prospective cohort; walking.

[TomBAvoider]

To me, a more interesting question I wish they disentangled, is to what degree the mortality benefits are down to the benefits of walking/steps per se, and to what degree the number of steps are simply a marker for less "sitting time" behavior. The fact that they adjusted for "exercise beyond walking" is not dispositive - because we know that excessive sitting time is unhealthy even if you exercise. Same with the "steps" and adjusting for exercise. It could very well be that it's a marker for less sitting time. In fact, I'd argue that the fact that benefits attentuate with more steps argues for it - if steps were beneficial in and of themselves, why would you have such a steep drop off? Seems that what "steps" really accomplish is prevent you from sitting.

Or at least that's a possibility, and I wish they'd disentangle that factor. How it could be done? F.ex. they could set up those who took a 8K step or 10K walk in one continuous stretch and then sat the rest of the time, vs those who took the same number of steps but sprinkled them throughout the day so they're not sitting for longer than say, 20-30 min at a stretch.

Until this is resolved we don't really know what the meaning is behind these correlations and the alleged benefits of walking. 

Also, looking at that graph, it seems the Japanese got lucky with that 10K steps thing - it may have initially evolved as a result of marketing and other non-health related reasons, but it happens to map pretty well to health benefits! 

[Ron Put]

6 minutes ago, TomBAvoider said:

To me, a more interesting question I wish they disentangled, is to what degree the mortality benefits are down to the benefits of walking/steps per se, and to what degree the number of steps are simply a marker for less "sitting time" behavior. ...

This could, and likely is, a factor, although I kind of like KHashmi316's "built-in Fitbit" hypothesis. :

Sitting Time and All-Cause Mortality Risk in 222 497 Australian Adults

 

But:

Sitting For Long Periods Is No Worse For Your Health Than Standing, Study Claims

 

[Mike41]

On 5/8/2020 at 6:09 AM, Dean Pomerleau said:

Yes I'm still walking that much. I think you may be confusing me with Tom. 

 

Welcome Elated!

Good point. But from the full text of the study, those very favorable hazard ratios for 8k and 12k steps per day relative to 4k were after controlling for the following potentially confounding factors in the researcher's Model 3:

Model 3: [sex, age] + diet quality, race/ethnicity, body mass index, education, alcohol consumption, smoking status, diabetes, stroke, coronary heart disease, heart failure, cancer, chronic bronchitis, emphysema, mobility limitation, and self-reported general health.

Her is the relevant table from the paper:

This implies to me that reverse causality can't much of a factor contributing to the apparent benefits of more walking. 

--Dean 

Problem here Dean is that they cannot control for genetic vitality! Seriously some people are just feisty and they are going to age well. Feisty people Are way less likely to sit on their asses all day. They are alive and engaged!

Edited June 8, 2020 by Mike41