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Free radicals and apnea

Thread Status: Hello , There was no answer in this thread for more than 60 days.
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New Member
Jan 18, 2002
Does anybody know how the practicing of freediving affect the release of free radicals in our bodies?
Got this reply on the APNEA mailing listHello all,

The following is taken from a book (The Zone, by Dr Barry Sears and
William Lawren), but rephrased and simplified.

“During the metabolism of food, a significant amount of free radicals
are formed. These free radicals are essential for the transformation of
food into energy. But excessive intake of calories, makes too many of
them. Ingesting greater than 500 calories of food at one time far
exceeds your body’s immediate energy needs. Flooded with excess food
and calories, your system strives to process and store the excess
energy. Free oxygen radicals are produced and spewed in vast amounts.
Any excess radicals not quenched by anti-oxidants are free to attack
other things, a process leading to oxidation of serum fats and damaged
cells. Adding up over the years, these insults lead to diminished
function and bodily deterioration. Too many free radicals can cause
heart diseases and cancer. At the same time, free radicals are some of
the most important weapons of our immune system, they kill bacteria
that cause diseases by entering our body. Without free radicals, it
would be impossible for our body to produce eicosanoids (some very
important hormones).”

I suppose this means that free radicals are not exactly an enemy. Too
few of too many of them are very bad, but in the right amount, they are
a very good friend. If you get too many free radicals, eating extra
anti-oxidants can kill them, but you have the right amount, those extra
anti-oxidants can kill the free radicals that you actually need. I
guess the ancient Greeks were right when they were philosophizing and
said that we need to have things at a “medium” amount.

I don’t know how training in the pool can lead to chlorine intake. If
it’s by absorption though our skin, maybe training with a suit can
minimize that. But I suspect that it’s mainly through our mouth and nose, when small amounts of water get in and find their way to our stomachs.

Panos Lianos
Athens, Greece

PS. Sebastian Murat complained that by training in the pool he noticed that his performance was going down possibly due to exposure to the chlorine in the pool.He started taking an anti oxidant supplement (grape seed) and felt his performance returning.
Hi All,

Like in any other sport, the body produces free radicals when freediving is practiced intensivly.

Our body suffers a lot of different kind of aggresions during our favourite activity.

Free radicals of course, but also intense dehydration, damage to the blood cells due to the pressure, hypoxia etc....are what the freediver has to face.

I'm always amazed when I see freedivers or spearfishermen spending hours in the water without even drinking a drop of water, and after they get out, eating a piece of industrial cake full of saturated fats or an burger with coke or beer.....

In freediving, nutrition is primordial!

With my trainer, we have spoken about free radicals and we arrived to the conclusion that the freediver should take a lot of antioxydants. There is no risk of overdose regarding what the body has to face during freediving.

My advice would be to take Vitamine C before freediving, drinking water and isotonic beverages during the dive session.
When you've finished the training, take your antioxydants and keep on drinking a lot.
Supplementation in Omega 3 and selenium will help to preserve the cell's membranes of the aggressions.

So, don't hesitate to change bad habits!

  • Like
Reactions: xristos
Thanks Fred,

glad to see that someone was able to give a precise answer to the question.
Great topic to read. I found this relevent research https://www.researchgate.net/public..._in_breath-hold_divers_after_repetitive_dives
And got me thinking. If you do 20 mins of dive time in 60 min session doing 20 seconds dives 40 seconds surface routine compared to a 20 min of dive time in 60 min session but doing 2 min dives with 4 min surface time which scenario would result in more oxidative stress, and by how much.
I suppose the 2 min dives would result in significantly more oxidative stress??
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