

Does Exercise Boost Immunity? - tokenadult
http://well.blogs.nytimes.com/2009/10/14/phys-ed-does-exercise-boost-immunity/

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percept
I recommend experimenting to figure out what works best for you.

My personal experience matches:

[http://www.runnersworld.com/article/0,7120,s6-241-285--
12386...](http://www.runnersworld.com/article/0,7120,s6-241-285--
12386-0,00.html)

IMO the studies cited there mirror the results with the mice, so the best bet
is to run the 30-75 minutes recommended in the Runner's World article, not
several hours as used in the experiments.

R.I.P. mice.

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sown
In the first experiment's and 2nd experiment's experimental group, it sounds
like the mice over trained. It's a commonly known phenomena among athletes and
these symptoms certainly sounded like it.

It would have been more interesting if they had trained the mice up over a
longer period of time and then exposed them to flu.

~~~
Goladus
Yeah, a big reason people exercise is for the long-term health benefits. Of
course the study is interesting, but not as something that should directly
affect personal workout routines.

~~~
electromagnetic
Exercise for officer workers is definitely needed, however there are serious
side effects to over-exercise. Not only can it be counter-productive
(increasing the time to actually get physically fit) but opens you up to
prolonged infections.

The big problem is that lack of rest between exercise can increase the risk of
strokes and other circulatory problems, which is extremely counter productive.
Damage to connective tissue and the consumption of muscle tissue during
exercise can have life long effects (for anyone who doesn't know, your heart
is a contractile protein, which is the type of protein consumed during
excessive exercise periods).

Regular and regulated exercise are the key to health, and it has to be a
regimen built for you. For some people over-exercise can be beyond a 20-minute
light jog, for others it's a marathon. Not everyone is a marathon runner or
body builder and believing differently is dangerous to your health.

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antirez
I do 30 minutes of treadmill every day (between 6 and 9 Km/h, with 4%-12%
inclination) and my feeling is that my body really enjoy this. It seems
natural btw that stressing too much the body is not a good idea for your
immune system.

~~~
electromagnetic
It's rather logical in fact. When you exercise you damage your body, keeping
your repair mechanisms active.

However overexercise typically does more damage in a session than your body
can heal before your next session. It's rather safe to assume that when you
contract a virus that when the immunological warfare is going on (our bodies
first response is rather brutal and untargeted, the sore throat from a flu
isn't from the flu, it's from your own immune cells killing - IIRC - roughly
20 healthy throat cells for 1 infected cell) and damaging our body that the
repair mechanisms are coping with all too much.

Not exercising doesn't put stress on our healing mechanisms, however it
doesn't keep them active and trained (so to speak). Put it this way, the
Police would take considerably longer to get to your house from the station
than from one of their patrol routes; essentially the same is for our healing
mechanism.

Even if exercise doesn't have an effect on our immune system, I'm sure it will
certainly increase recovery time (assuming you're not on the treadmill when
sick) by decreasing healing time, which is ostensibly the factor that kills
you and not the virus itself (assuming you haven't contracted the 1918 Spanish
flu).

I've only ever had one noticeable case of the flu (which happened when I moved
country, so I'm unsure if it was a strain I'd never experience, similar to the
current H1N1 'pandemic'), which I believe is due to frequent exercise (a job
involving heavy lifting ~90lbs and constant weight carrying ~10 lb tool pouch
and ~10lb hammer drill).

~~~
antirez
Thanks, interesting explanation. Maybe another factor is the change in blood
pressure, because while you exercise parts of your body that normally receive
little blood, will receive a lot more, and blood carries antibodies that may
kill viruses before they start to spread in the rest of the body.

I noticed that sometimes when I had a start of a cold, but still feeling well,
to exercise lead to a stop of the infection.

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kentosi
What's missing here - and which you can't really test with mice - is the
emotional side of things.

Exercising because you've been placed on a treadmill, as was the case with the
mice, is akin to people exercising because they "have to", or get a trainer to
"stay motivated". When you actually do it because you "want" to and it feels
good it's a different story because the feelgood chemicals have a lot to do
with your immune system.

For many years during my late teens and early twenties I went to the gym so
that I could get buff and be fit. I hated exercise, but forced myself to do it
and pushed through the pain. Yes I even got a personal trainer at one stage.
The results? I either got sick, injured myself, or just plain depressed (at
the lack of results), only to repeat the cycle over and over again.

Back to this article - what I'm trying to say is that stress, anxiety,
happiness all play a HUGE part in your immune system (and fitness).

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scott_s
I do regular strenuous training, and this makes sense to me. You are weaker
immediately after a strenuous workout than immediately before. That's why
adequate recovery time is just as important as workout time. It makes sense to
me that immediately after the workout, before your body has had a chance to
recover, your immune system is weakened and you're more susceptible to
illness.

Personally, what keeps me coming back to my workouts is the challenge. I'll
take the extra risk of the occasional cold or flu over the risk of dropping my
workouts entirely from disinterest.

~~~
fauigerzigerk
Don't forget that the immune system doesn't just fight the flu, it also fights
cancer.

~~~
scott_s
I also risk my life daily by driving a car. There's a point at which you have
to accept the risks of certain activities to lead the life you want.

~~~
fauigerzigerk
Absolutely, just what many smokers tell me and they are right. I just think we
should at least know about the risks.

~~~
scott_s
Ha, I've never had my workouts compared to smoking. My workouts have many
other positive benefits, which I think outweigh the risks. Smoking has no
positive benefit other than it's something to do while sitting in bars.

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terpua
Like anything in life, it's about balance. Eat healthy and balanced diet and
exercise 3 to 4x a week. If you over extend yourself, you will get hurt or
sick. Ditto if you do nothing and overeat.

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bombs
The answer is no; it decreases it.

My personal experiences match the findings of these studies. My diet and
supplement use is much better during heavy training and exercise periods, so
I'm hoping that that will offset it.

~~~
diN0bot
er, what about the second experiment, where light exercise reduced infection
to 12% versus 50% for no exercise and 70% for 5x as much exercise?

that seems to suggest that doing a little bit of work keeps the body healthy.

furthermore, the study doesn't say what the mice did before the experiement.
perhaps the mice were used to 20-30 minutes of exercise a day, and it is
change that is most damaging. what one mice considers exhausting, another
mouse might find boring.

edit: the article mentions "(Although definitions of intense exercise vary
among researchers, most define it as a workout or race of an hour or more
during which your heart rate and respiration soar and you feel as if you are
working hard.)"

~~~
learnalist
Not going to touch on the finer points of the atheltisim of the mice. As your
right it would clearly alter the results.

But I do have a question.

What is the ratio of 30 minutes of exercise for a mouse compared to a human.
As I would be highly surprised if its 1 to 1.

This article reinforces the need to listen to your body and react accordingly.

On a side note for those looking for ideas.

Based on the example in the article...

I would happily volunteer to take a saliva test before running and after. To
help build up the data available for the test.

A website to cater for "crowd sourced data" scientific discovery would be an
amazing site. ( clearly there would be pitfalls, im just throwing it out there
)

~~~
mediaman
patientslikeme.com is doing crowdsourced "scientific discovery." I use quotes
because of the obvious difficulties in having proper scientific procedures in
crowdsourced efforts, but nevertheless I think it's useful.

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tybris
Were the mice in shape?

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metra
The comments in this thread will revolve around running. Running is the main
form of exercise accepted by HN.

Forget playing team sports or weight lifting. Cycling might crack through HN's
barriers once someone experiments with pedaling barefoot.

~~~
catzaa
My exercise regime involves taking the stairs to my apartment. I also keep all
my snack food and cigarettes in my car.

~~~
eru
How many flights of stairs? I used to live in floor 5, and can run up all the
way without getting out of breath. However I tried to run to floor 16 in a
hotel a few days ago, and was powered out around floor 8.

~~~
catzaa
Just 6 flights - but it is fairly high (each level is fairly high).

At work it is 13 which is better exercise (the lifts are also shaky so the
stairs at least feels safer).

