
American Runners Have Never Been Slower - notdang
https://runrepeat.com/american-runners-have-never-been-slower-mega-study
======
szemet
_' It has been a popular belief that the increase of the average marathon
finish time is due to the fact that participating in running competitions is
gaining popularity. With the popularity increase, the number of not so fit
participants rises, and the average finish time increases.

This argument is not exhaustive.

Let alone that in the last two years (2015 and 2016) numbers of participants
are declining and the finish time in all the four major race distances is
still growing.'_

This is a wrong argument. It is enough if just running in general gains
popularity. If you take races as a sample from the running population the
sample size does not mean that much - the average/median/percentile
performance of the sample (if it is representative) may follow the performance
of the whole running population!

This is the case for example if the racing population is a uniform random
sample. But it may even happen that nowadays larger proportion of slower
runners are going to races - because races are much more advertised/known for
the hobby joggers than in the past, while elite runners were there always...

~~~
spunker540
I feel like this counter-argument is glossed over and not thoroughly refuted.
The stats go back to the 80s and yet it's not till the last two years that
participation starts to decline? I think it's very likely that more and more
amateurs are signing up for smaller races that didn't previously exist.
There's probably enough variance that one year of decline is not enough to
prove that participation increase is not a factor.

Also, I think there's a chance that the running races are losing some of their
top athletes to triathlons which are also growing in popularity.

~~~
alistairSH
Triathlons, off-road running races, obstacle races (tough mudder, etc), and
other races that aren't plain running.

Local to me, there are also a few extreme distance races (longer than
marathon), usually on hiking trails.

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wgjordan
Interesting claim but I'm not quite convinced based on the data presented.
They considered the hypothesis ('myth') that increased popularity of running
is what's slowing down the average times by looking at 100th-finisher times
and nth-percentile times, but this does not control for an increased number of
_races_ being held each year to accommodate all the extra runners.

~~~
kazinator
It doesn't need to control for that. The new people who get swept up into
participation in running events are invariably the slow ones. Conducting
larger and more frequent races to fit them in is neither here nor there.

In a road race held somewhere in America in 1975, it would all have been
largely highly fit, fast people from a track and field background.

~~~
kurthr
Interesting, the goal of the fastest runners must not be to finish highly, if
it were, they would distribute themselves to the additional races so that they
had a better chance of winning. Instead, the claim is that they each keep
running in the same races as they did before so that the slower runners do not
have lower finishing places. Wait, not that either since then those new low
finishes at the new races would be slower.

I note that they don't look at the top 3 finishers of big races... because
those times have been falling (like the US Nationals).
[https://en.wikipedia.org/wiki/USA_Marathon_Championships](https://en.wikipedia.org/wiki/USA_Marathon_Championships)

An economist might say that was impossible (for competitive people to deny
themselves a precious placing goal), I simply find that it's unlikely.

~~~
moruno28
The top runners will continue to go to the major races (New York, Chicago,
Boston) because they can compete with the best runners in the world, there are
appearance fees for elite runners, and they offer better exposure for athletes
who depend on sponsorship dollars to make a living.

As for the US Marathon Championships, America's best marathoners usually skip
that race (aside from when it serves as the Olympic Trials) because smaller,
less prestigious marathons that pay less prize money are often chosen to serve
as the US Championship. Why (relatively) smaller marathons? So that your US
champion actually wins the race (like they would at the Twin Cities Marathon)
instead of finishing somewhere in the top 5 (but not first) at New York.

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eksemplar
Can't popularity explain this? Marathons used to be for an elite of first
movers, then everyone joined and the elite left to do ironman and other sorts
of crazy extreme.

I mean, this is a personal theory that I've basically pulled out my ass right
this instant, based solely on what I've seen my coworkers do, so it's probably
completely ridiculous. But in my network the people who were the fastest at
running marathons aren't running marathons anymore.

~~~
raverbashing
Yeah I think this is also a possibility

(to be honest, healthwise, Marathons are very bad exercises - they're
extremely biased towards aerobic capabilities - just check the amount of
muscle mass a marathon runner has)

Also running for 3h straight is extremely boring and repetitive

~~~
phicoh
This argument doesn't make much sense to me. Running is hard on your body
sure. Lots of load on muscles and joints.

But then you use as argument 'extremely biased towards aerobic capabilities'.
This argument doesn't make any sense. People have only very limited capability
of anaerobic exercise. At the same time people are build to exercise
aerobically almost forever.

~~~
raverbashing
> People have only very limited capability of anaerobic exercise. At the same
> time people are build to exercise aerobically almost forever.

Hence the need for balance

(though sports at the Olympic level are rarely healthy, I'm betting on the
swimmers, short range runners (not 100m though), rather than the marathoners
to be the healthiest)

~~~
phicoh
Running a marathon is risky because of the load on muscles and joints. That's
specific to running. Doesn't have anything to do with extreme aerobic
exercise.

If you replace running with equivalent amount of cycling then there are no ill
effects. You can easily cycle at a recreational level for 8 hours a day and
see no ill effects. Muscle structure will be quite similar to distance
runners. They just don't wear out as much.

~~~
alecst
> If you replace running with equivalent amount of cycling then there are no
> ill effects. You can easily cycle at a recreational level for 8 hours a day
> and see no ill effects. Muscle structure will be quite similar to distance
> runners. They just don't wear out as much.

I once thought this too, but I have come to think that this is a myth. It's
what my doctors and physical therapists (and friends) say -- if you're injured
running, pick up cycling.

I injured my knee cycling and haven't been able to do it in years. It's a
chronic pain that starts when I hop on my bike, and only then. (I have had the
full fit, bike sizing, and all that.)

I began running instead and have never felt better. I do it barefoot, but I
don't know if that's relevant.

It's now hard for me to accept that cycling is easy on one's joints. Maybe it
is true, but if it is true, it's not obvious. Our bodies are very good at
running and walking. There is no reason to think they are good at cycling. A
bike is a rather unusual and modern invention.

I can speculate that maybe it's the shoes that are contributing to injuries in
distance runners. I am not sure. Feel free to reply if you feel I am wildly
off.

------
spyhi
As soon as I saw the headline, I thought to myself "well yeah, Americans have
also never been fatter," so the conclusion wasn't much of a surprise.
Interesting that it's affecting men so much more.

This isn't the only study that indicates fatness is impacting aggregate
performance, either. The US DoD has actually identified American obesity as a
potential threat to national security and readiness. [1][2]

[1] [https://www.usnews.com/opinion/blogs/policy-
dose/articles/20...](https://www.usnews.com/opinion/blogs/policy-
dose/articles/2016-04-05/obesity-is-a-national-security-threat) [2] (PDF)
[http://www.dtic.mil/dtic/tr/fulltext/u2/a547350.pdf](http://www.dtic.mil/dtic/tr/fulltext/u2/a547350.pdf)

~~~
trentmb
> I thought to myself "well yeah, Americans have also never been fatter,"

Do fat Americans run?

~~~
eesmith
Some do.

But "fatter" != "fat". [http://www.webmd.com/men/news/20041027/average-weight-
for-am...](http://www.webmd.com/men/news/20041027/average-weight-for-
americans-growing-heavier#2) points out that Americans are over 10kg heavier
than the previous generation, but that's classified as "overweight" not
"obese".

~~~
revelation
It's not a discrete scale, ceteris paribus every single kg will make you
slower and increase injury risk. It's continuous.

~~~
eesmith
If you wish to phrase things that way then feel free to reinterpret the
discussion chain thusly:

1) spyhi used a continuous scale: "also never been fatter"

2) trentmb switched to a discrete scale: "Do fat Americans run"

3) I replied to that question, that yes, "fat Americans run", objected to
trentmb's discretization of a continuous scale, and gave a pointer to a paper
regarding BMI, which assigns categories like "overweight" and "obese" to the
continuous scale.

Your comment comes across like you think I didn't know the difference between
continuous and discrete, when that was the point of my response.

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mirekrusin
Picking up arbitrarily trends - obesity in this case, even though plausible,
still doesn't feel right, ie. you could also choose average global temperature
or %-age of CO2 and it would probably match the trend as well.

Also they're not addressing more complex implications - ie. if %-age of women
(who are slower) increases and directly it doesn't account for total slowdown
(as they've shown) maybe it has indirect impact on other runners (males) who
are running _together_ with more slower participants (women).

I think assumption that people tend to run at the paste of people around them
is not completely out of place compared to assumption that obesity slows down
marathons.

------
spectrum1234
I thought this study was going to be about the top percentile. I would assume
this percentile is getting faster (competition is increasing in all sports at
the top level).

Obviously on average Americans are getting slower because they are getting
fatter. This almost isn't news.

~~~
watwut
Through, average Americans don't run marathons at all. It is only self
selected smaller subset that does it (or is even able to finish it).

------
logicallee
(This comment references bodyweight. While not normative, some readers may
wish to skip it.)

\--

I am _usually_ quite critical of misreported findings but I must say the
article does seem to support its findings pretty clearly. If they had a plot
of it, I would expect to show over this period another effect: "amateur
marathon finishers have never weighed more, or been slower." Obviously this is
my speculation and if found as I predict it would be a statement that _even_
those who care enough about their health to train for, run, and finish in a
marathon, have been weighing more and more.

I say this as a prediction because it is a very strong effect throughout the
population. It certainly trumps any other health changes that have affected
the population as a whole over the same period.

This data may be possible to estimate retroactively, visually based on
photographs and footage of races - telling 15% from 25% from 35% from 40%
bodyfat (for both genders) may be possible based on photographs alone. (With
low fidelity.)

For comparison, although I couldn't find a chart going to 2017, this article
includes weights for Americans as a whole through 2010:

[https://www.washingtonpost.com/news/wonk/wp/2015/06/12/look-...](https://www.washingtonpost.com/news/wonk/wp/2015/06/12/look-
at-how-much-weight-weve-gained-since-the-1960s/)

It is interesting to compare with the data we have just seen.

-

EDIT: I have edited this following a downvote. If there are specific
objections I can edit it further or remove it.

------
kutkloon7
I can't say that the study fully convinces me (I agree with szemet, not all
counterarguments are carefully refuted).

There is however, a very different standard in the US, compared to other
countries. In the Netherlands (and other countries), I am considered to have a
normal or even slightly athletic posture. In the US, people consider me to be
very skinny.

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in_cahoots
I don't understand why they rule out the increasing proportion of female
runners. The fact that the trends are different for the genders doesn't negate
this as a possibility. And they even state that this accounts for 46% of the
effect. To me this reads more as an agenda-driven investigation than an actual
study.

~~~
rrobukef
Both men and women are getting slower. Men much faster than women. So:
Americans are becoming slower.

The myth tries to be the explanation for the average running time getting
slower. It falsily implies that because more women join, people aren't really
getting slower. This is false: people are getting slower.

------
sgt101
I don't have the data, so the authors might be right, but honestly reading
this that's the best gloss I can put on it.

The second last chart (they aren't numbered, because this is a study done by
someone with a mathematical analysis Ph.D and a statistician, apparently) says
it all - we've plotted two things and we have fitted a line and then we state
a conclusion. I'm sorry, but stop the seminar there.

The first two points, what does the line look like if we remove those? What do
you mean by average? Can we have error bars on the points to cover 90% of the
population? What are the distributions of the finish times? If they are
normal, how come - aren't there elite and club peaks as well as everyone else?
Did we try excluding the registered runners?

The questions are endless and this study is "not exhaustive" \- back to R
guys.

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averagewall
Aren't marathon runners mostly competing against others in the same race, so
if they can all slow down, they all will? Some of the olympic races seemed
like a farce with runners right next to each other - obviously adjusting their
pace according to each other, not trying to set a record.

~~~
mannykannot
I think that applies to the top runners, who are competing with a few other
specific individuals, but a typical marathon runner will be competing against
the clock, if anything. In a race in which no participant is paying any
attention to any of the other competitors, they will each still end up running
with others going at about the same speed, assuming their pace does not
fluctuate erratically (which it doesn't - especially in longer races, where
almost all participants have practiced enough that they have an intuitive
knowledge of what they can realistically expect to achieve.)

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notacoward
Hey look, I'm part of a trend! :D

But seriously, I'm a bit confused. Early on, they refute "Just the slow are
getting slower" but near the end they make almost the same claim. The trick
they play is to shift from examining the N fastest to examining the N slowest.
In other words, the two samples "prove" nearly contrary things because they're
both incomplete. Also, the real meaning of N fastest/slowest changes a _lot_
with race size. Using percentiles would have been a better (and more obvious)
choice.

BTW, I love RunRepeat and have used it extensively as part of my research the
last several times I've bought running shoes. Highly recommend.

------
afpx
Isn't this a good example of why people shouldn't just crunch through a big
dataset looking for a correlation to support a claim that they already believe
is true?

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TheAlchemist
My first thought was also that it's simply due to the growing popularity of
running. However this is also the case in Europe.

I've checked some random results - the difference is crazy. In Europe the
median time seems to be around 1h55, while in the US ones it was more like
2h15-2h20 ! Which is very bad indeed

~~~
watwut
Male marathon world record is 2:02:57 and female is 2:17:01. It is unlikely
that median marathon time in Europe would be faster then world record.

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chrismealy
Marathons were cool in the 70s and 80s. Now athletic people are into different
sports.

~~~
puranjay
All the pop science I've read in the last decade has been saying the same
thing: running on roads will screw up my knees, that long distance running is
not great for either losing weight or gaining muscle, and that you should do
intense running instead.

------
puranjay
Slightly off topic, but this is a great example of an affiliate site done
right. It's comprehensive, unbiased and has some really interesting content.

------
djmips
brainstorming: Has timing got more precise over time? Is it something in the
atmosphere that's changed over time? Has the threshold of pain willing to be
endured been reduced in our culture? Perhaps there is better awareness about
the downsides of pushing through pain and injury.

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mamon
Nice thing is that they claim p-value of 0.01, much better than usual 0.05.

------
decker
Given that they haven't done random sampling of the US population over time,
the correct title should be "population of american runners who choose to run
marathons are getting slower."

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kazinator
The results could simply reflect the increasing popularity of participating in
running events. The influx from new people is going to drags the performance
averages down.

~~~
eesmith
Quoting from the article: "It has been a popular belief that the increase of
the average marathon finish time is due to the fact that participating in
running competitions is gaining popularity. With the popularity increase, the
number of not so fit participants rises, and the average finish time
increases.

This argument is not exhaustive.

Let alone that in the last two years (2015 and 2016) numbers of participants
are declining and the finish time in all the four major race distances is
still growing."

~~~
kazinator
You have to look at where the attrition is coming from; what is the
demographic shift in the running population. Also, everyone is a year older
with every passing year.

If you want a sport to stay vibrant, you have to have the fit youngsters
coming in at the bottom, and the old people retiring out the top. This is not
controlled in any way in public mass participation sport like in pro sport.

Really, this whole thing is meaningless. When I first saw the headline, I
thought it would be about competitive running at the collegiate level or
whatever.

Nope! Clickbait about changing jogger demographics.

~~~
eesmith
What you say now is true, and not analyzed in the article.

It is not the same as your original statement regarding a simple increase in
popularity.

------
koliber
Why does everything have to be a race issue?

------
juskrey
Healthy people don't run marathons

~~~
paulcole
Just curious, but what cherry picked study and unique definition of health are
you basing that statement on?

