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Ammonia in breath or sweat after exertion or strenuous exercise

  1. Oct 6, 2014 #1


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    I've been doing some long bike rides (50+ miles) on routes which include long (several miles) of low to moderate grades, or short distances of 3 to 8% grades.

    I've experience what smelled like ammonia or amines while exhaling through my nostrils, or while drinking and breathing heavily. I've been searching for information on the matter, but most often, the commentary is found on various sites related to health and fitness, and the respondents may not be licensed physicians, or folks with medical degrees. So, I'm looking for reliable sources on the subject.

    As far as I can tell, at some point, I'm metabolizing protein, whereby my body is converting protein to sugar. One response on a website indicated:
    I think this is probably correct, but I need to verify with reliable sources.

    Another respondent indicated ketones, e.g., acetone, but as I recall, there is a fruity smell to ketones, and the smell was more like ammonia, although it did have a metallic taste.

    Apparently folks on high protein, low carbohydrate diet can experience similar symptoms, and apparently the resolution is to increase the carbohydrates and reduce protein, although consuming whey protein after such exertion may be indicated.

    Catabolism refers to processes in which large molecules into smaller units to release energy, so that applies to breaking polysaccharides into simpler sugars, or proteins into sugars, and so on.

    Gluconeogenesis is a metabolic pathway that results in the generation of glucose from non-carbohydrate compounds such as pyruvate, lactate, glycerol, and glucogenic amino acids.

    It is the metabolism of proteins rather than carbohydrates that is of particular interest to me. I clearly have to consume more carbohydrates or sugar before or during the ride. The other affect is that during heavy exertion, I've been told that the digestive process shuts down, so it would not be helpful to eat just before strenuously exercising.

    I would appreciate any articles in medical or sports medicine journals on the subject.

    My goal is to do 100+ mile rides, and preferably with an average speed above 15 mph. So far on my 50+ miles rides, I can do 15 mph or better, even with the hills.
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  3. Oct 7, 2014 #2


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    If you're engaging in a physically demanding exercise or workout regimen and you think something may not be right with how your body is responding to this sustained activity, bite the bullet and see a physician. There are plenty of people who, while outwardly appearing healthy, dropped dead while engaging in light exercise or casual activity, because of some hidden, undiagnosed condition. How our bodies respond to a given level of activity can also change as we age, so it's a good idea to get a physical examination before you start marathoning across the countryside or kayaking across the ocean. When you do talk to a doctor, make sure he understands your training program and the goals you have set for yourself.

    The motto, "Physician, heal thyself" is only applicable if you are already a physician. Don't take chances with your health.
  4. Oct 7, 2014 #3


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    This brings to mind the story of a serendipitous discovery by a physician who, while drinking with a friend, noted that the froth on his friend's beer would collapse a little each time his wheezing friend exhaled across the top of his glass. Physician concluded there must be a surfactant (?) present in his friend's breath, and acetone here could indicate diabetes. Subsequent tests confirmed his suspicion.
    Last edited: Oct 7, 2014
  5. Oct 10, 2014 #4


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    Your quote sounds good. The ammonia cycle:
    http://web.campbell.edu/faculty/nemecz/323_lect/Nitrogen_metabolism/images/ammonia-transport.jpg [Broken]

    Pretty much sums it up. Typically when patients have "ammonia" or urine smelling breath that is medical buzzwords for kidney disease. That is the short end of it only though and one of those associations you are supposed to make as a doctor for testing purposes. The truth is it could be any number of things which give someone's breath that characteristic odor, such as having an enzyme deficiency which means they're a slow excreter, a fast producer, a liver problem, a kidney problem etc. People live for years with enzyme deficiencies and never know until the system is stressed (ask me my story about a patient with a mild OTC deficiency who got steroids some time :p).

    Anyway, I echo SK. You ought to see a doctor. Explain what is going on. A run of the mill ammonia level, hepatic and renal panel probably wont cut it, though they are good places to start. More elaborate biochemical testing, possibly before and after exercising, in your future I see :).
    Last edited by a moderator: May 7, 2017
  6. Oct 14, 2014 #5


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    I did go see a urologist who seemed familiar with the matter (he also enjoys cycling). I had some tests done, and asked questions. He didn't necessarily have all the information I'd like, but it's a start. He did mention that with heavy strenuous exercise, muscles can start releasing protein and amino acids into the blood stream. I need clarification from a doctor familiar with such

    He mentioned that I should drink more water, and possibly change my diet before riding. In the ride I did 8 days ago, I drank more water, tropical juices and Gatorade, and the smell of ammonia was less frequent, but still appeared particularly after riding upgrade.

    This may be relevant -
    Last edited: Oct 14, 2014
  7. Oct 14, 2014 #6


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    Proper hydration during exercise is important, not only to keep your body from becoming overheated, but also to help the kidneys cleanse the bloodstream of the products of metabolic activity. If your kidneys don't have enough water available, some of this stuff could crystallize into a kidney stone, and that's a world of hurt you don't want to experience.
  8. Oct 15, 2014 #7
    i sent this to a friend who bikes 100+ miles a week, perhaps it will interest you as well. heavy/intense biking will exhaust the supply of calcium in your bloodstream, leading your body to raid the bone structure, which is probably not such a good thing.


    <blockquote>The NWB athletes had significantly lower BMD of the whole body and spine than the WB athletes, despite having similar age, weight, body mass index, body composition, hormonal status, current activity level, and nutrient intakes. Sixty-three percent of NWB athletes had osteopenia of the spine or hip, compared with 19% of WB athletes. Cyclists were 7 times more likely to have osteopenia of the spine than runners, controlling for age, body weight, and bone-loading history. </blockquote>

    bmd = bone mineral density
    wb = weight bearing
    nwb = non-weight bearing
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