Road Bike, Cycling Forums banner
1 - 8 of 8 Posts

·
Registered
Joined
·
5,613 Posts
Discussion Starter · #1 ·
a friend of mine forwarded these references to me; curious if anyone has examined this issue (the amounts of C and E in the study aren't that high - a serving of Endurox contains 400IU of E, the amount in the 2nd study). 2nd study also has a population of previously trained athletes.


Oral administration of vitamin C decreases muscle mitochondrial biogenesis and hampers training-induced adaptations in endurance performance.
http://www.ncbi.nlm.nih.gov/pubmed/18175748


Antioxidants prevent health-promoting effects of physical exercise in humans.
http://www.ncbi.nlm.nih.gov/pubmed/19433800
 

·
Registered
Joined
·
21,624 Posts
Vitamins

stevesbike said:
a friend of mine forwarded these references to me; curious if anyone has examined this issue (the amounts of C and E in the study aren't that high - a serving of Endurox contains 400IU of E, the amount in the 2nd study). 2nd study also has a population of previously trained athletes.

Oral administration of vitamin C decreases muscle mitochondrial biogenesis and hampers training-induced adaptations in endurance performance.

Antioxidants prevent health-promoting effects of physical exercise in humans.
You have to be very careful with these kinds of studies and read them closely. I'm not going to take the time to do that for you, but will rather make some general observations.

First, there have been a number of "miracle" vitamins identified over the years which seem to help when the person's diet contains high concentrations, but as supplements don't work or are even detrimental. Vitamin E has a bit of that taint to it. You are "always" better off to get your nutrients via quality food because apparently it is a combination many micronutrients in food (as opposed to isolated nutrients in pills) that really seems to work. Far better to eat an orange than to take vitamin C.

Second, a lot of these studies are on very small groups of people, so the statistics are sometimes weak.

Third, it is very difficult to do quality nutritional studies because 1) different people react differently to any given nutrient mix and 2) it is very hard to hold "everything else constant."
 

·
Registered
Joined
·
1,096 Posts
What kerry said (Kerry are you an MD?)

But there is some thought (that is gaining acceptance) that supplementing with vitamins and antioxidants to stop "normal" repsonse to exercsie may not actually be a good thing. Free radicals are generally not a good thing, but they may be a part of the post exercise signalling pathways that lead to further adaptation. Cytokines are another one.

It is deffinately a young area of research.

As kerry said, eating a variety of real food, with thier natural vitamins, minerals, and antioxidants is the best from an overall health perspective.

We did a relatively small (20 people) study to see if Mona Vie (that wine bottle anti-ox juice) actually effected blood antioxidants. There was no significant difference in our study.
 

·
I'm just watching a dream
Joined
·
138 Posts
Kerry Irons said:
a lot of these studies are on very small groups of people, so the statistics are sometimes weak.
Yes, first study was done on 14 people. They were give a whole gram of vit C which is 13x more than the daily recomended value of 75mg.

Second study only had 39 people and they were given 1 gram of C and 270mg of E which is about 260mg more than reccomended.

Kerry = nail on head
 

·
Registered
Joined
·
5,613 Posts
Discussion Starter · #5 ·
I was more interested in how the papers relate to the more general issue of exercise creating an endogenous antioxidant defense capacity in response to exercise induced oxidative stress. This is an interesting (and somewhat surprising) area. The second study was pretty well-designed (one reason why it was published in PNAS). The supplementation levels weren't higher than what many in sports performance typically suggest (and would be reached in athletes who use sports nutritional drinks etc). It also had a sub-population of previously trained athletes, which is more representative than the typical untrained subjects...
 

·
Registered
Joined
·
1,096 Posts
The whole concept of cytokines, ROS, and other markers of inflammation may be somewhat misunderstood, and is deffinately missunderstood by the lay public.

The difference is athletes (or people who regularly exercsie) vs. Seds. It is pretty well known that almost all of these "markers of inflammatin" are bad in Seds and indicate a metabolic problem or maladaptation. But in athletes, they appear to potentially play a critical role in metabolic adaptations to exercise. Blocking them leads to less "marker" of adaptation. If this reduced "marker" of adaptation leads to reduced performance is a different question that is harder to address.

IL-6 is a perfect example of a missunderstood cytokine. High IL-6 in seds has been shown to be associated with many conditions. But increased IL-6 after exercise may be a neccessary signal to adaptation.

Further, are these "markers" truely needed for adaptation. COX inhibitors such as ibuprofen block muscle protein synthesis acutely after resistnace training. See link below. But there are numerous people who take close to this dose daily and still gain skeletal muscle mass. So the question is, would they gain more mass over time if they did not take the ibuprofen. That study has not been done (to my knowledge).

http://ajpregu.physiology.org/cgi/reprint/292/6/R2241

Typically, the differences are so small in trained athletes, that they do not make a "difference" or enough of a difference as to be readily apparent. As I said, peformacne outcomes are never the designed outcome of studies and likely will not be. Those studies would need large subject sets to find difference in peformance if it existed. And unfortunatly performace is very low on the list when funding studies. We have a TON of money trying to find out how to keep Seds from getting sick......

When the simple answer is more exercsie and less calories.
 

·
Registered
Joined
·
21,624 Posts
Secret knowledge

sdeeer said:
the simple answer is more exercsie and less calories.
Somebody on this board used to have the following signature line:

"So if you eat less and exercise more, you'll lose weight? Who else knows this?"

I love it!
 

·
Impulse Athletic Coaching
Joined
·
5,576 Posts
sdeeer said:
The whole concept of cytokines, ROS, and other markers of inflammation may be somewhat misunderstood, and is deffinately missunderstood by the lay public.

The difference is athletes (or people who regularly exercsie) vs. Seds. It is pretty well known that almost all of these "markers of inflammatin" are bad in Seds and indicate a metabolic problem or maladaptation. But in athletes, they appear to potentially play a critical role in metabolic adaptations to exercise. Blocking them leads to less "marker" of adaptation. If this reduced "marker" of adaptation leads to reduced performance is a different question that is harder to address.

IL-6 is a perfect example of a missunderstood cytokine. High IL-6 in seds has been shown to be associated with many conditions. But increased IL-6 after exercise may be a neccessary signal to adaptation.

Further, are these "markers" truely needed for adaptation. COX inhibitors such as ibuprofen block muscle protein synthesis acutely after resistnace training. See link below. But there are numerous people who take close to this dose daily and still gain skeletal muscle mass. So the question is, would they gain more mass over time if they did not take the ibuprofen. That study has not been done (to my knowledge).

http://ajpregu.physiology.org/cgi/reprint/292/6/R2241

Typically, the differences are so small in trained athletes, that they do not make a "difference" or enough of a difference as to be readily apparent. As I said, peformacne outcomes are never the designed outcome of studies and likely will not be. Those studies would need large subject sets to find difference in peformance if it existed. And unfortunatly performace is very low on the list when funding studies. We have a TON of money trying to find out how to keep Seds from getting sick......

When the simple answer is more exercsie and less calories.
You are obviously un-American by spewing this logical nonsense. The answer ALWAYS comes in a pill.

/thanks for the good post
 
1 - 8 of 8 Posts
Top