Re: Running in marathons impairs immunity

On 11/20/2003 4:29 PM, John 'the Man' wrote:
> Once upon a time, our fellow jmk
>    rambled on about "Re: Running in marathons impairs immunity."
> Our champion De-Medicalizing in sci.med.nutrition retorts, thusly ...
>
>
> > Why do you think that 90 minutes should be the maximum duration of 
> > continuous exercise?  You stated, "90 minutes should be the maximum 
> > length for all workworks, particularly for continuous exercise 
> > activities."  I could find nothing to support that either in the article 
> > that you posted or elsewhere.
>
>
> The question of whether YOU personally found support is different from
> the question: Is there proof.
>
> I couldn't care less, if YOU personally found no support for my
> contention.
>
> I provided the proof.  It is called a published research study.  :)

The thing is, what you posted did not prove what you stated.

The article states that "when people exercise for 90 minutes or more 
without taking a break, carbohydrate stores in the body drop."  It does 
not say anything about workouts being restricted to a maximum of 90 
minute's YOU said that.

The article states, "This is consistent with public health
guidelines urging individuals to engage in near-daily physical
activity of 30 minutes or more."  The research study does not mention a 
maximum duration.  YOU DID.

The article states, "Many components of the immune system exhibit 
adverse change after prolonged, heavy exertion lasting longer than 90 
minutes," however, earlier on it says "The infection risk is amplified 
when other factors related to immune function are present, including 
exposure to novel pathogens during travel, lack of sleep, severe mental 
stress, malnutrition, or weight loss."  This does not either state or 
imply that the maximum duration of continous exercise should not be 
longer than 90 minutes.

Furthermore, if you look to researchers beyond the one that published 
the artilce that you referenced, you will see that the recommendation is 
to use startegies other than reducing the duration of exercise:
"Strategies to prevent URTI in athletes include avoiding overtraining, 
providing adequate rest and recovery during the training cycle and after 
competition, limiting exposure to sources of infection, ensuring 
adequate nutrition, and possibly vitamin C supplementation."
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10910293&dopt=Abstract

> If you don't agree with that study, then I couldn't care less.  :)
>
> Just thought that you might want to know. :)

--
jmk in NC