A couple weeks ago, I set a PR bench pressing (150% of my body weight). Right afterwards, I stood up exhausted but satisfied and started to help clear the weights off the bar. At that point I felt a little light headed and noticed the distinct smell of ammonia. The light-headedness is easily explained as a lot of blood was redirected to muscles for the lift. But the ammonia smell really caught me off guard. I mentioned this to my trainer, and he started to explain, but got a phone call, then got sidetracked. So I left the gym that day feeling really good, but wondering about the smell.
Searching online didn't give me any real answers at all. There are lots of reports where people are sweating and smelling like ammonia, but this was not happening here. What I experienced lasted only a couple seconds, but it really seemed like I was actually exhaling ammonia. I couldn't find any real information about that. I also read where people sometimes smell like this when on the Atkins's Diet and their body starts breaking down proteins because they have no carbohydrates left in their system to burn for fuel (i.e., they've entered ketosis).
It will typically take several days or longer for a healthy person to enter ketosis on a no-carb diet. I am far and away nowhere near a low-carb diet. I try to eat a lot of protein, but low-carb is NOT me. Plus, you don't instantaneously go into systemic ketosis.
A bit more reading, thinking and discussing, and then talking to my trainer today has let me piece together a little more of the story. Turns out your body has only a limited amount of energy on hand for immediate use. You'll burn through this in 3 to 5 seconds of sustained maximum exertion. Once you've pushed through and burned that available energy out, your body switches modes to continue supplying energy as quickly as possible. The easiest thing for your body to break down is protein (basically amino acids), so this is where it goes first in the reserves under this condition of maximum exertion. (Still following?) Amino acids all have an "amino group" which is NH2. Ammonia is NH3 - see the connection now? So this nitrogen group is not going to be used by your body in it's strive for more energy, so it's a waste product. In ketosis, it'll probably be blood-born and eventually re-used or flushed away by the kidneys. In the short-circuit version of the cycle going on here, I guess it's just exhaled.
This bench press I did probably lasted 4 to 6 s4econds. My body was probably entirely energy starved and started breaking down proteins to keep me going, at which time I exhaled ammonia for a few seconds (surely less than a minute). After the 100% exertion stopped, my body quickly stabilized and went about it's normal activities.
DISCLAIMER: Even though I have 2 graduate degrees, I last took biology in 10th grade. I took 2 semesters of Chemistry in college, but it was "chem for engineers" and not bio-chem or anything that rigorous.
I may have all this completely wrong. In this case, I welcome any and all corrections. However, let me again point out that it was
not my sweat that smelled like ammonia, but it was "inside my head", hence my assumption that I was exhaling it. This explanation seems plausible enough to me to put forward.
Discussing this today and given my workout history, that day I was probably exactly at 100% of what I could do. Not 2 pounds either way, but right there. I had already done squats with about 200lb on the bar (I'm told you have to add in your body weight for an accurate measure there, but it's easier to track the bar), and felt good and strong. All the pathways were open and my body was rested and ready to work. I imagine that having done one more lift earlier in working up to that weight, or adding a few more pounds to the bar for that attempt, probably would have resulted in a crushing defeat where I just couldn't get the bar moving upwards. But that day I was able to do it. Probably with my body using every bit of energy it had available to it. Good job, body.
At least nowhere on line did I find "if you smell ammonia in your head, it's probably brain cancer"!
