Re: Running in marathons impairs immunity

In article <[EMAIL PROTECTED]>,
 Lyle McDonald <[EMAIL PROTECTED]> wrote:

> Van Bagnol wrote:
> 
> > Seems that the near-obssessive concern about "impaired immunity" is
> > unfounded in this case anyway. The Nieman immunology findings were for
> > continuous intense activity lasting more than 90 minutes. The workout
> > described is neither continuous nor intense, and, excluding the breaks,
> > barely hits 90 minutes. Running 12 miles in 90 minutes nonstop would be
> > different.
> > 
> > Anyway, the easiest way is simply to see if you get sick after your
> > workouts. If you do, then cut back.
> 
> Reminds me of an old Calvin and Hobbes cartoon
> 
> Calvin: How do they determine the weight limit on bridges?
> Dad: Well, they drive heavier and heavier trucks over it until it
> collapses, then they rebuild it.
[snip]
> Your recommendation is pretty stupid is what I'm getting at.  It would
> be like seeing what weight in the bench press will break your arm by
> increasing the weight until it breaks.  Well now you know.  Sorry,
> that's moronic.

Then you misinterpreted my post. Read my past writings in this thread. 
Your reductio ad absurdum analogy is an overreaction (see below), but it 
does reminds me of a Will Rogers quote that predated it.[*] :-)

> The effect of high intensity or high volume training on immune function
> is well established.  Others have mentioned some strategies to limit it.

I'm aware of and don't doubt the (short- and long-term) effects of 
exercise on immune function (NK/T-cell counts, cytokines, MHC 
expression, yada yada yada).

The context was to address the alarmist concern of "John 'Da Man'", 
whoever he is, that his seemingly light workout was impairing his immune 
system. My advice was that if he's not getting sick, then there's no 
apparent need to cut back.

I didn't say to _increase_ his workouts _until_ he lands in the 
hospital. However, if he _is_ getting sick, then he should reduce them.

> Consuming carbs before,during and after the workout is a huge one.  It
> helps to limit the cortsiol and IL6 response, both of which are
> implicated in the problem.  Chronically elevated IL6 has also recently
> been implicated in the overtraining/underperformance syndrome which
> makes proper carb intake that much more critical during periods of high
> intensity or volume training.
>
> Neiman (in the chatper on immune system function in "Endurance in 
> Sport") also suggested 600 mg/day of vitamin c for the week prior to 
> a marathon. Proper sleep/recovery, avoiding rpaid weight gain and 
> avoiding other life stresses are other recommended strategies.

But Nieman also mentions that the apparent reduction in postexercise 
URTI associated with prophylactic Vitamin C intake occurred in a study 
of _ultramarathon_ runners; a Vitamin C supplementation study of 
subjects running 'only' 2.5 hours had no significant effect.

The description of the workout in question met none of the parameters 
outlined by Nieman as being risk factors for noticeable immune system 
depression, as far as I see: it was below the radar of marathon-level 
intensity, and in fact seemed closer to the moderate intensity at which 
Nieman et al suggest net _positive_ immune effects and a _reduction_ in 
reported symptoms of illness. If Nieman's chapter in _Endurance in 
Sport_ has more information to shed light on it, please post it. I'm 
open to seeing it.

Perhaps the poster has neglected to mention other stressors; maybe he's 
just lost 30 pounds, gets 4 hours of sleep, and is going through a 
divorce and a bout of the flu. If so, he should have mentioned them. But 
if he is, my advice is the same. Absent any deleterious circumstances 
surrounding the workout, reduction is not indicated.

> But training until you get sick and concluding that you did too much and
> should cut back is just a retarded recommendation.

I'd agree that it's incomplete, but that's not what I said. If that's 
what you thought, I'm sorry for the misunderstanding. 

Van

[*] "First, you buy a stock. If it goes up, sell it. If it doesn't go 
up, don't buy it." -- Will Rogers

-- 
Van Bagnol / v a n at wco dot com / c r l at bagnol dot com
...enjoys - Theatre / Windsurfing / Skydiving / Mountain Biking
...feels - "Parang lumalakad ako sa loob ng paniginip"
...thinks - "An Error is Not a Mistake ... Unless You Refuse to Correct It"