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View Full Version : Is Vitamin C Sabotaging your Training?


MattTuck
11-05-2015, 08:51 PM
Not sure if this has been discussed before... Would be interesting to get a take on this from our resident human physiologist. :banana:

Scientists have always struggled to understand exactly how short, few minutes, intense interval exercises can produce similar effects to much more time consuming endurance trainings.

High intensity interval training, also known by its acronym HIIT, has become very popular in recent years with beginners, professional athletes and patients with reduced muscle functions as it has clear health benefits. Now, researchers from Stockholmç—´ Karolinska Institutet discovered cellular mechanisms behind the positive benefits of HIIT and why endurance training is undermined by antioxidants.

Short bursts of just a few minutes of exhausting physical activity can prepare muscles to work harder, boosting the production of new mitochondria (powerhouses of the cells, generating the energy that our cells need to do their tasks), which culminates endurance enhancement much like more time consuming endurance training. High-intensity exercise triggers the breakdown of calcium channels as a result of an increased production of free radicals (highly receptive radicals which can act as oxidants for cellular metabolism). The muscle cells thus have anti-oxidative systems for trapping and nullifying the radicals.

The scientists also discovered that antioxidants like Vitamins C and E, very common ingredients of dietary supplements, remove the effect on the calcium channels, resulting in the weakening of the muscle response to endurance training.


Hakan Westerblad, a professor of physiology and pharmacology, said :

å¾¹ur study shows that three minutes of high-intensity exercise breaks down calcium channels in the muscle cells.
This causes a lasting change in how the cells handle calcium, and is an excellent signal for adaptation, such as the formation of new mitochondria.
Our study shows that antioxidants remove the effect on the calcium channels, which might explain why they can weaken muscular response to endurance training and they also show that the calcium channels aren稚 affected by the three minutes of high-intensity interval exercise in elite endurance athletes, who have built up more effective antioxidative systems.

The research included male subjects who cycled for 30 seconds for maximum-exertion, followed by 4 minutes of rest and repeat this routine 6 times altogether. Twenty-four hours after the test, tissue samples of their thigh muscles were taken and revealed an increased rate of free radicals, showing that just a few minutes of intense exercise is all it takes for benefits to kick in.

The research has been published in the journal PNAS in an article: è¿·yanodine receptor fragmentation and sarcoplasmic reticulum Ca2+ leak after one session of high-intensity interval exercise?

http://www.thelatestnews.com/scientists-discovered-why-can-high-intensity-interval-training-match-endurance-training/

ultraman6970
11-05-2015, 10:14 PM
What I would love to know is why multivitamins get me so weak that I have to go to sleep. I know some forumites have the same problems, it sucks.

Dead Man
11-05-2015, 10:42 PM
Well I sure as ···· hope not... I take 750mg of ascorbic acid daily, for iron absorption.

benb
11-06-2015, 07:48 AM
What I would love to know is why multivitamins get me so weak that I have to go to sleep. I know some forumites have the same problems, it sucks.

Does your multi-vitamin have some "herbal package" added to it? I'd look at that. It's like they took a little bit of every damn thing off the chinese traditional medicine shelf and jammed it in the vitamins without reading the known side effects. (A lot of those herbs have no scientifically proven benefit but do have scientifically proven side effects.)

AngryScientist
11-06-2015, 07:50 AM
Paging Joachim....

Cicli
11-06-2015, 07:53 AM
Good thing there was no mention of hops in that article.

Mikej
11-06-2015, 08:10 AM
So, but, caffeine really disrupts calcium channels? Which was not in the study?

atrexler
11-06-2015, 10:11 AM
Really interesting article. Love me some biochemistry.

Worth pointing out that the effect they're studying was not observed in elite endurance athletes (7 cyclists and 7 runners who were "at least competitive" at the national level). They reference studies showing that endurance training improves anti-oxidant response to muscle activity, which is exactly what they see in the current study. Elite athletes showed higher levels of several proteins that have anti-oxidant function post-HIIT, whereas untrained individuals didn't. Consequently the elite athletes' muscle cells were able to better cope with free-radical load after HIIT, and so there was no effect (or less effect) on their RyR1 channels. Meanwhile the untrained individuals did not respond as effectively to the free-radical load, and consequently got fragmented RyR1 channels.

So, I think its a really intriguing mechanism for how relatively untrained individuals can see rapid muscle adaptation from HIIT, but seems like the effect is much less pronounced or altogether absent in trained individuals.

Also worth clarifying that its not really like you want tons of free-radicals ravaging your cells. These molecules damage proteins (like RyR1) and DNA and generally cause mayhem, cell death, and cancer. Cells have many, many mechanisms to deal with free-radical damage, to prevent these bad outcomes. Really neat that they're mechanistic in muscle adaptation, it seems. So anyway I don't know if anyone should necessarily avoid vitamin C...

Joachim
11-06-2015, 10:34 AM
Short version, well trained individuals still need to do endurance to get the adaptations. Untrained will benefit from HIT training in terms of mitochondrial density. Caveat regarding Vit C. High levels are pro oxidant and low levels are anti oxidant. Too much oxidative stress will lead to cell death and you don't want to kill your mitochondria do you? So on the end you want optimal levels for anti oxidants but not so much that your adaptations are nullified. I've published a few papers on oxidative stress and protein signaling. If anyone wants them, PM and I'll send the pdf your way on Monday.

AngryScientist
11-06-2015, 10:35 AM
let's not underestimate the threat of scurvy.

that's something that'll put a dent in your training regime: scurvy.

Idris Icabod
11-06-2015, 11:33 AM
Where's Linus Pauling when you need him! He took grams of the stuff every day, then again I'm pretty sure I could whoop him on a bike.

gasman
11-06-2015, 02:02 PM
Where's Linus Pauling when you need him! He took grams of the stuff every day, then again I'm pretty sure I could whoop him on a bike.

Especially since he has been taking a dirt nap for 20 years.

Louis
11-06-2015, 02:38 PM
http://www.appforhealth.com/wp-content/uploads/2011/01/caveman+cartoon-300x300.jpg

Ken Robb
11-06-2015, 03:44 PM
http://www.appforhealth.com/wp-content/uploads/2011/01/caveman+cartoon-300x300.jpg

Really Funny! Thanks

Tickdoc
11-06-2015, 04:19 PM
Not a fan of vitamins....or drinking 10 gallons of water a day.

Our requirements are minimal, and the bulk of them are just urinated away, given a decent diet of course.

I like to ingest fresh fruits and vegetables ( and nuts) for any vitamin uptake, and drink only when I'm thirsty. Unless it's beer.:beer:

You know what they say...you are what you eat!