Sweatology: Why some people sweat more and the affects on the body

Do you ever wonder why some people sweat more than others? If you belong to a gym, then I am sure you know someone who regularly sweats profusely during their warm-up. Puddles of sweat! Maybe you’re that person? Why does this occur more for some than others? The answer to this phenomenon requires an explanation as to what the actual process of sweating does for our body and when it begins.

Simply put, sweating helps regulate your core body temperature control. As the sweat on your skin evaporates, the heat that was contained within that sweat dissipates into the air and therefore your core body temperature is better regulated. Sweating technically delays the buildup of heat in your body by disbursing that heat through release of your sweat.

Okay, so now that we know why we sweat (temperature control), we can start to analyze why some do it more so than others. There are actually many factors that determine this, although scientists are still analyzing the reasons and to what degrees these factors play a hand in our differences. We’ll start with what scientists believe are the weakest factors for sweating and we’ll work our way up to the most influential.

The temperature of the environment and the equipment the individual is using or wearing has a significant impact on the amount of sweating the individual does. If an individual is wearing a heavy firefighter’s coat and helmet and carrying large loads over long distances, it kind of goes without saying that that individual will sweat more than the person doing the same thing in a t-shirt and shorts. Heat and equipment makes a big difference in those athlete’s body temperature control. They are likely going to sweat considerably!

Fitness levels of the individual is another influential reason an individual might sweat more. While the influence on sweating of the equipment used and the temperature outside is very simple to understand, the fitness level of someone is a little more complicated. The original understanding was that as an individual became more fit, that person’s body would begin to sweat at a lower temperature in response to the conditioned stress that the body was used to being put under. This would aid the person in their ability to control the temperature of their body better and allow them to work harder and longer during an exercise. But there were flaws in the study that came to that conclusion. When a more recent evaluation was conducted, studies indicated that individuals will sweat more not just because they are more physically fit, but also because they have the physical capacity to work harder and get hotter, which in turn will begin the cooling process of their body. But ultimately sweat rates have less to do with even fitness levels, and more to do with gender and genetics.

Currently studies show that men tend to sweat on average more then women, all things being equal.

The gender of an individual seems to prompt a little bit of our human history to be considered. If we look back at the hunter/gatherer timeline of our human history it seems that that dynamic helped shape the way we modern humans sweat. Males were known to be the main providers for food from hunting, so when they were prompted with hotter temperatures and heavier workloads they had no choice but to continue the hunt until the animal was caught, lest they risk the loss of everyone’s dinner. Their bodies were conditioned to sweat more due to these conditions. Whereas the females of the same group gathered supplies/food, they would recede back into the shade and cool areas of their environment when prompted with higher temperatures or heavier workloads. This resulted in the females of the group sweating less. Over time these conditions became part of our genetic makeup through evolution. Currently studies show that men tend to sweat on average more then women, all things being equal.

Genetics play the largest roll in who sweats more. If your parents tended to sweat a lot, then so will you. If they didn’t then you’re typically going to be drier. This simple factor weighs the heaviest on who sweats the most. Studies show this to be true. So, if you sweat a lot, chances are likely that one or more of your parents did as well.

If you consistently drink more than your body actually requires (more than you thirst), then you run the risk of hyponatremia.

While this information is interesting, it is not very helpful until we consider how to replenish the sweat that dissipates. Many believed that drinking water until you could drink water no more was the appropriate way to rehydrate yourself. Just the opposite is actually true. If you consistently drink more than your body actually requires (more than you thirst), then you run the risk of hyponatremia. This is a condition that occurs when sodium levels in your bloodstream fall below 135 mmol/L. It is very unlikely you will die from dehydration, but over-hydration is a serious concern with at least 18 cases of death since 1993. Symptoms can be as bothersome as irritability and fatigue, or as serious and life-threatening as nausea, vomiting, seizures, and coma. These then lead to brain-swelling and death.

The key is to just drink to thirst. Individuals should not be trying to finish as much water as they can stomach during their exercise. This will result in diluted sodium levels in the bloodstream which increases the risk of hyponatremia. Some people sweat more than others as we previously discussed, but also some people tend to lose more sodium in their sweat than others and that ultimately is the greatest concern. If you tend to notice a salty residue coming off your t-shirt after a workout (rings of salt on your shirt is a sign as well) then you are probably losing a large amount of sodium when you sweat. One thing you can do to combat this is to take supplemental salt tablets or capsules. These will help replenish what you’ve lost better than sports drinks will by far. In fact, sports drinks will only hinder your ability to replenish them. Sports drinks tend to only have about 2g of sodium per liter. In one study football linebackers lost 30g of sodium in one afternoon session of training. Said linebackers would require approximately 65L of sport drinks to get that much sodium put back in them. Unfortunately, this is not only impossible (On average, men filter 1 liter of water per hour; while women filter about 800 ml/hour) but this would also then lead back to hyponatremia. Additionally, drinking more fluid than your body is able to process means you will gain weight. Another serious reason not to over drink. Who wants to workout just to gain weight? Most people work out for the exact opposite reason.

The bottom line is drink water to thirst, and replenish lost sodium with salt tablets not sports drinks. And, if you sweat more than others, you’re most likely at a disadvantage, but that is just life. Get over it; sweat is a normal body function. Now get back to that workout!

References:

https://www.ncbi.nlm.nih.gov/pubmed/20696786

https://www.ncbi.nlm.nih.gov/pubmed/20617911

http://library.crossfit.com/free/pdf/CFJ_Sweat-Achauer7.pdf

Written By David Russo — Edited By Megan Russo