Why Do We Puke When Exhausted?

[stuartSan]

Did a search on this forum, Google, and Wiki on every word to do with puking (yes, even regurgitating[sp?]) and exhaustion.

No avail.

So I wondered if any of you happen to be as curious as I am and managed to find the answers.

I don't like puking after HIIT sometimes and not understanding why.

[deadlyshaolin]

Strenuous exercise ==> buildup of lactic acid ==> nausea/vomiting

or so the thinking goes...

[Centaur]

Hmmm, I've been wondering this myself. A couple week ago one of my sparring partners puked and he asked our trainer if that was "ok". My trainer responded with "if you're not puking, you're not working hard enough." I don't think he was serious, but it led me to wonder exaclty what it is that causes someone to throw up.

The lactic acid buildup could be one, but how does that effect your stomach/bile duct? Is it the strain on the CNS and maybe something to do with blood flow, or rather the lack of it?

I really hope someone know the answer to this.

EDIT:
OK I just googles "puking exercise" and this was the FIRST thing that came up:

The Gastrointestinal System and Exercise
It's well established that intense exercise (e.g., >85% VO2 max) shunts blood away from the GI tract and slows down digestion and absorption. However, at exercise intensities that ultra cyclists use, digestion is not impaired, provided hydration is maintained.

from Ultracycling

They were more concerned with 2 hours + endurance type training, but a good start anyhow.

[tri4ben]

Also of note is the fact that it is difficult to puke when you are doing an endurance sport hard, but when you finish is when the nausea sets in and you feel like puking. I have never puked during a race, only after. But I have puked during a basketball game.

It is also hard to sneeze when you are doing an endurance event.

[deadlyshaolin]

hey redrum, if you really want to know...

The sensation of nausea and subsequent retching/vomiting is controlled by the vomiting centers in the reticular formations of the medulla (in your brainstem). It receives signals from four sources:
1. the chemoreceptor trigger zone (see below)
2. visceral nerves from the GI tract (ate something bad, stomach flu, food poisoning, etc)
3. visceral nerves from outside the GI tract (e.g. gall bladder stone causing you to vomit, heart attack causing intense nausea, etc)
4. nerves from the extramedullary centers in the brain (e.g. bad odors, fear, motion sickness, brain injury)

What I want to focus on is #1, the chemoreceptor trigger zone. This "zone" is located in your brainstem and gets activated whenever an abnormal systemic, whole-body event is happening, like hypoxia, diabetic ketoacidosis, uremia, vomit-inducing drugs, AND IN THIS CASE, lactic acidosis.

The decrease in pH caused by lactic acid buildup gets sensed by your chemoreceptor trigger zone, which tells the vomiting center in your reticular formation that should be nauseous and possibly vomit.

[MikeMartial]

^^^The Doc is a wise sage indeed.

And just to add, you puke when you "stop", because your systemic clearance of lactic acid stops.

[initialdproject]

Originally Posted by MikeMartial

^^^The Doc is a wise sage indeed.

And just to add, you puke when you "stop", because your systemic clearance of lactic acid stops.

So the leason learned? Never stop.

[MikeMartial]

Originally Posted by initialdproject

So the leason learned? Never stop.

Or learn to work in your lactic acid threshold without blowing chunks.

[Centaur]

WOW...thanks alot, Mr.Shaolin. i think today was one of my most enlightning days on Sherdog, with this and the whole whey/casein thread.

Again, much appreciated.

[stuartSan]

Nice info. Now I have a better idea, thanks.

Used to think the blood flowed out of my brain which is why I felt nauseaous an out of my stomach too which is why I puked, haha.