
Hourly 4-second sprints prevent impairment of postprandial fat metabolism - wallflower
https://journals.lww.com/acsm-msse/Abstract/9000/Hourly_4_s_Sprints_Prevent_Impairment_of.96302.aspx
======
Gys
'Hourly 4-second sprints' is actually 5 times an hour 4 secs (bicycle)
sprints. So it is more precisely about every 12 minutes. I do not understand
why it says 'hourly'? Because it sounds less often?

~~~
gdulli
It must be one set of 5 reps per hour, not one sprint every 12 minutes.

That's how exercise usually works, and the study is concerned with the "least
amount of exercise that can acutely improve fat metabolism and other aspects
of health". Activity spaced out every 12 minutes would be disruptive and
defeat that purpose.

~~~
logfromblammo
Article states 4s activity followed by 45s seated rest, repeated 5 times. So
you're actually occupied with the workout task for 4m+05s every hour, even
though only 20s of that is sprinting.

~~~
SketchySeaBeast
And it's not an activity you'll do at or near your desk, so you're going to
have to travel somewhere to do it.

~~~
jnwatson
It depends on your desk.

~~~
SketchySeaBeast
True. And the location of said desk.

------
tofflos
> This study determined if the interruption of prolonged sitting (i.e.; 8-h of
> inactivity) with hourly cycling sprints of only 4-s duration each (i.e.; 4-s
> x 5 per h x 8-h = 160-s per day; SPRINTS) improves PPL. The 4-s sprints
> employed an inertial load ergometer and were followed by 45-s of seated
> rest.

So you would need to take a 5 x (4-s sprint + 45-s rest) = 245 seconds
exercise break from work every hour and in return you could get the following
results?

> No differences (p>0.05) between interventions were found for plasma insulin
> or glucose AUC. However, SPRINTS displayed a 31% (408±119 vs. 593±88
> mg/dL/6h; p=0.009) decrease in plasma triglyceride incremental AUC and a 43%
> increase in whole body fat oxidation (P=0.001) when compared to SIT.

Does "whole body fat oxidation" mean that the an average male calorie burn of
2500 per day would be multiplied with 1,43 to 3575 calories per day?

~~~
mikekchar
> Does "whole body fat oxidation" mean that the an average male calorie burn
> of 2500 per day would be multiplied with 1,43 to 3575 calories per day?

It seems extremely unlikely to me. I hesitate to bring up the 2nd law of
thermodynamics because I know if frustrates a lot of people in these
discussions. However, bear with me.

"Calories" in this context refers to kilocalories. Burning 1 kilocalorie
produces enough energy to raise 1 kg of water 1 degree C. So burning an extra
1000 kilocalories per day means producing enough heat to raise the body
temperature of a 100 kg person 10 degrees over the course of a day. Although
our bodies are really good at cooling, that's not an insigificant amount of
heat. It's of a magnitude that is relatively easily measured.

If such a phenomenon were to exist, it seems inconceivable to me that the
researchers would not try to measure it. I mean it is literally the holy grail
of dieting. I think it is considerably more likely that the effect they are
measuring is very interesting, but does not extrapolate out to this logical
conclusion.

~~~
covidSurvivor19
Your analysis seems to be in the right direction but I think that the body
uses this energy in many more ways than just heat. Moving muscles, pumping
blood, keeping ionic gradients in the kidneys, and in cells, producing waste
products, do seem to take energy. Also, consider the water we lose due to
evaporation just by breathing, we are constantly creating a significant amount
of heat and dissipating it into the environment. This extra 1000Kcal would be
roughly a 50 watt increase in average metabolic rate during a whole day.

It does seem a bit high but anecdotally, my body temperature is 1C higher on
days I do some tennis early in the morning. And more importantly my oftenly
cold hands go away, so radiating more of it away.

~~~
mikekchar
The thing is that because of the 2nd law of thermodynamics, that energy does
not go away when we use it. Moving muscles, pumping blood, etc uses energy and
transforms it to heat. It's a bit weird that energy doesn't go away when we
"use" it, but that's how the universe works :-) What _can_ happen is that
energy is locked up in chemical structures (or, I guess as physical potential
energy). So if you evaporate water, the energy goes into the water and stays
there until the vapour condenses. Things like that. But it's pretty easy to
isolate a person and measure the amount of heat they produce (to a gross level
like we are talking about here).

But, yes. Exercise will drive your metabolism and cause you to be warmer.

~~~
StavrosK
It's easier to measure the volume of exhaled air and extrapolate calories from
that, via CO2 expelled.

~~~
usrusr
Different fuels create different amounts of CO2 per joule though. This is not
just a truism in combating climate change but also a key tool when observing
metabolism. Whenever someone gives numbers for how much of some exercise
energy consumption is from fats and how much is from carbs it is determined by
measuring CO2 output and comparing that to measured energy output.

~~~
StavrosK
Oh huh, I hadn't realized that, thank you!

------
huffmsa
Ah, the sprint is being rediscovered once again for it's ability to squeeze
maximum effect into minimum working time.

If you get a chance, try to find a copy of "A System of Multi-year Training in
Weightlifting" by A.S. Medvedyev (a translation of the 1980s Soviet Olympic
Weightlifting program for coaches).

It's the culmination of decades of studies across the entire Soviet athletics
program about what works and what doesn't.

The summer programming shifts almost exclusively to sprinting, and only a few
hundred meters per day, because that's what they found is enough work for
anyone who isn't a specialized running athlete.

I follow it as soon as I can ever summer and it's immediately obvious that my
metabolism increases.

IMO the secret about sprinting vs distance running is that your body can't
optimize for efficiency. You can marginally increase ATP capacity, but the
only thing getting better at maximum effort sprints does is make you able to
produce more power while doing maximum effort sprints. It stays hard, without
needing to increase volume much over time.

~~~
lejboua
Can you plz share how do you incorporate sprints in your training plan?

------
cjohnson318
"Four men and four women participated in two trials"

I'm not a medical researcher; is this a normal size for a study?

~~~
monkeypizza
Say you are trying to distinguish between a placebo and a cyanide pill; test
subjects are young rats (base rate of death extremely low). How large of a
sample size do you need? I think one control, one test subject is enough to be
certain, because the base rate of death is insanely low, when measured on a
per-minute basis.

Sample sizes can be small and still very significant when the effect is large.

~~~
gvjddbnvdrbv
I would want about four of each rat still. The control could die of something
else...

~~~
samatman
I'm quite confident the only reason to use four rats in a study of cyanide is
that you really want to kill two rats.

~~~
steerablesafe
Yeah, because you already have a very well-established prior on the effects of
cyanide.

------
Drakar1903
And here I thought this was about software development.

~~~
zadjii
According to the [site
guidelines]([https://news.ycombinator.com/newsguidelines.html](https://news.ycombinator.com/newsguidelines.html)):

> Hacker News Guidelines

> What to Submit

> On-Topic: Anything that good hackers would find interesting. That includes
> more than hacking and startups. If you had to reduce it to a sentence, the
> answer might be: anything that gratifies one's intellectual curiosity.

> Off-Topic: Most stories about politics, or crime, or sports, unless they're
> evidence of some interesting new phenomenon. Videos of pratfalls or
> disasters, or cute animal pictures. If they'd cover it on TV news, it's
> probably off-topic.

I'd say this falls under "anything that gratifies one's intellectual
curiosity."

~~~
James_Henry
I think they were trying to make a joke about sprints and agile software
development.

------
exabrial
I'm 7 pounds into the "Covid 15" despite daily exercise. I may give this a try
and see if I see results

~~~
knicholes
Right before the pandemic, I entered a body composition challenge that just
ended. I lost ten lbs of fat and gained one lb of muscle. Another guy lost 6
lbs of fat and gained 4 lbs of muscle. You can't trust your scale. Go by the
scale in addition to how you look, how your clothes fit, and your body
measurements.

For better data, get a Dexa body scan.

~~~
exabrial
There's only a handful of them[Dexa] in the USA, if I want to find something
local (Kansas City) what should I be looking for?

~~~
knicholes
I'm from Utah, so I really have no clue, but a quick search revealed this:
[https://www.dexafit.com/locations/kansas/kansas-
city](https://www.dexafit.com/locations/kansas/kansas-city)

~~~
exabrial
NICE, thanks, something I'll look into

------
anentropic
Now _that 's_ Agile

~~~
davio
We've found that continuous flow works better than 4-second sprints.

------
puranjay
This study used cycling sprints. I wonder if a similar effect would be
observed with say, a set of pushups or squats every hour

~~~
chronogram
Leg muscles are a lot larger. You can easily stay warm while cycling or
walking at a brisk pace in the winter. Less so when standing still and doing
pushups or situps.

------
jhaddow
Who has time to do 4s sprints???

~~~
wscott
yeah because after my 4s sprint it will take me 20s to walk back to my desk.

~~~
SketchySeaBeast
Past the rest of the open office floor-plan as sales stares.

------
neurobashing
It was strange at first, when everyone got their Apple Watch and started
standing up, seemingly at random, in meetings. “Gotta meet my stand goal!”

Gonna be really weird when they go tear-assing down the hallway

~~~
myself248
Oop, someone's got the zoomies!

------
PacketPaul
Ok 4s/hour. 8 hours/day of sitting. So 32s day of total exercise!?!

Still probably will not do it.

~~~
benjaminl
That is also how I initially read it, but the paper states that there were 5
sprints per hours for a total of 160 seconds a day.

From the paper:

> i.e.; 4-s x 5 per h x 8-h = 160-s per day

~~~
dr_dshiv
Still probably would not do it. But why?

I wonder what other exercise modality this could be replaced with. Do 3
squats?

~~~
swader999
1 flight of stairs.

~~~
samatman
a good comparison!

Sprinting up a flight of stairs, then walking back down, and repeating it five
times, once an hour.

That I have a good gauge of. Yeah, that would feel good. Pity I live in a
first-floor flat...

------
zebnyc
Don't we need to warm up before doing any max intensity exercise to prevent
injury.

~~~
Barrin92
I've read conflicting information about warming up over the years but it at
least appears to me that the consensus is slowly moving away from several
common exercises such as stretching, which apparently even seems to have
negative effects.

~~~
3131s
Static stretching should be avoided at the beginning of a workout.

I had assumed this was about sprinting in the sense of running as fast as
possible, which would be absolutely insane to do without a warmup. I take
around 20 minutes to warm up for sprinting, doing very specific exercises to
prepare.

On a stationary bike though, because the range of motion is much more
controlled, I can see it being a little less of an issue.

~~~
huffmsa
Since you're doing this every 12 minutes, you'd stay relatively warm all day.
American football players don't need to warm up every time they come off the
sidelines

~~~
3131s
But they do... lots of teams have stationary bikes on the sidelines. No
athlete would sit motionless for 12 minutes in the middle of a competition,
not too mention that players would go through a much longer warm up before the
game.

But I agree that going full force very briefly on a stationary bike with no
warmup is probably fine for most people.

~~~
huffmsa
Fair, but a lot of them do sit on the bench and do some moderate walking at
most.

I'd expect people doing these regular sprints to be more aware of their body
and move around more in anticipation of the next set.

------
sAbakumoff
I am curious if the same effect could be achieved if I just jump on jumping
rope for 20 sec every our? I can even jump for a minute!

------
pazimzadeh
The control group was asked to sit for 8 hours straight, whereas the
experimental group sprinted five times. It would be more interesting if they
compared it to standing up.

~~~
masklinn
> whereas the experimental group sprinted five times

Per hour.

------
99_00
If tried an intense exercise, regardless of how long, without warming up I
would hurt myself really fast.

------
jvln
Searching for exercises having an efect and taking as less time as possible
looks like panacea.

------
mirimir
OK, so what's a "4-s sprint"?

I presume that this employs a stationary bicycle. But against what resistance?
Also, four seconds hardly seems enough to even reach maximum exertion.

------
mahesh_rm
Jumping cold out of your couch/chair and sprinting 5 seconds every hour,
multiple times a day, sounds to me like an optimized 'quickly destroy most of
your body joints' routine.

~~~
bradlys
To me - it sounds like a great way to throw up or at least get stomach
sickness.

I can't imagine going full send with no warm up and not suffering some sort of
issue after stopping.

~~~
huffmsa
Your warm-up accrues though. You're doing a little bit of exercise every 12
minutes for 8 hours.

You're not going to get sick.

~~~
EForEndeavour
Nitpick: the 4-second sprints weren't evenly distributed into each hour. They
were done in sets of 5 with 45-second rest periods between sets.

------
rkagerer
How about jumping jacks?

~~~
mywittyname
Probably not, jumping jacks don't take much effort. Think about for how long
people can sprint at their maximum speed: 3 minutes would be world class. But
doing 3 minutes of jumping jacks is pretty easy.

------
rawland
TL;DR:

An hourly ~5min cycling exercise on a stationary bicycle trainer results in a
31% decrease of area under the curve (AUC)* of postprandial triglyceride
levels in blood plasma and a 43% increase in whole body fat oxidation.

The cycling exercise consisted of five 4-sec all out sprints followed by
45-sec rests.

The exercise was performed once per hour during 8 hours of sitting and
compared to 8 hours of pure sitting.

[*]: [https://stats.stackexchange.com/questions/132777/what-
does-a...](https://stats.stackexchange.com/questions/132777/what-does-auc-
stand-for-and-what-is-it)

------
valuearb
> Four men and four women participated

Is all exercise science this weak?

~~~
rodonn
sadly, almost all of it is based on samples around this small.

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jordiburgos
p(0.05) and p(0.0001) with 8 people sample? It is hard to understand those
probabilities.

------
gfxgirl
I'm confused. "Hourly 4s sprints" sounds like one 4 second sprint every hour
but the second paragraph of the summary says

> Purpose

> This study determined if the interruption of prolonged sitting (i.e.; 8-h of
> inactivity) with hourly cycling sprints of only 4-s duration each (i.e.; 4-s
> x 5 per h x 8-h = 160-s per day; SPRINTS) improves PPL. The 4-s sprints
> employed an inertial load ergometer and were followed by 45-s of seated
> rest.

That's 5 per hour not 1 or once every 12 minutes

~~~
mgraczyk
Every hour, they do a workout that consists of 5 repetitions of 4s sprints.

~~~
Freeboots
Ah, this is probably what they meant. Very poorly explained by them.

~~~
m463
Jira is confusing too.

~~~
danmur
Especially if your sprints are four seconds long

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throwaway55554
> "Prevent Impairment"

So, is that a double negative and this would mean it improves fat metabolism?

------
xchaotic
This was done on purpose Every hour but you can get similar results with one
longer Training session. Heck I only train 3-5 days per week and problem
burning fat with enough intensity or volume.

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onetimemanytime
>> _" Four men and four women participated in two trials"_

My uncle smoked 3 packs a day and lived to 90.

other than that, maybe just getting up and putting strains even for seconds
might do the job /trick our body.

------
pantulis
I think this is mostly a curiosity.

Why do people think this is relevant for HN? Is people seriously trying to
"hack" their metabolism? What for? Being able to spend, say, 16 hours sitting
in front of a computer typing code away?

~~~
lvturner
As I get older, I more and more realise the negative health impacts of a
mostly sedantry job - anything to offset that is surely in the interests of
most HN readers

