If you're like me, you sweat a lot, but maybe you live on the other side of the coin and you don't sweat very much. Either way, it's really important to know how much weight you're losing when you're working out to know how much you should be drinking. I'm Jesse Funk and on today's episode of Runner's High, we're going to talk about how to calculate what your sweat rate is.

If you're an endurance athlete, and most likely, if you're here with me on Runner’s High, you probably are, it's especially important for you to figure out what your sweat rate is. Or more importantly, if you do traffic on because the longer your race goes, the more water you lose, the more you need to replenish. So, here's the part where I say, if you hate math, don't worry I'm going to do it for you. So, subscribe to the channel as a way to say thank you. If you do like math, subscribe to the channel anyway because we're gonna get along great.

As you work out your muscles are slowly losing water because you're sweating. And when they lose water, they're not able to operate at maximum efficiency anymore. So, that's why we're trying to figure out what your sweat rate is and how much we can take in to replenish it so we keep our muscles operating as optimal efficiency as your workout. Which, like I said before, is very important for us endurance athletes because we work out for a very, very long time.

So, how do you do that? I'm about to get into the mathy section. And since I'm an American, I want to do these things in pounds. But the whole equation makes a lot more sense in metric. Don't worry, I will do the conversions and show you how to do the conversions. It's pretty straightforward. So, follow along with me inside to the equation and show you how to calculate what your sweat rate is.

The basics of this equation is we're taking our pre-workout rate, remember this is without clothes, this is your actual weight, and then your post-workout weight. You're going to have to subtract those two, and then you have to add back in any kind of water you've taken in. So, you have to keep track of how much liquid you take in during a workout. For you gross swimmers out there, if you're peeing in the pool, you need to calculate that as well. But that may be a little bit tough. Don't pee in the pool. Stop it.

Anyway, so once you've done that, then you have an idea of how much weight you've lost. Well, you can take that divided by the amount of minutes and that essentially gives you your sweat rate per minute, which we can calculate into an hour. I'm going to go through an example with me as I swam yesterday, took my weight and we'll figure out exactly what my sweat rate is for that hour workout in the pool. So, stay with me as I do the mathy part here and give you an example of what I actually did yesterday.

So, before I got in the pool, I weighed myself at 167.7 pounds. My workout lasted about 45 minutes, and then my post-workout weight was 165.5 pounds. Remember I said we need to take those pounds and convert them into kilos because this whole equation makes more sense in metric. Now, without me going into a long diatribe about why metric makes more sense and kind of pooh-poohing on all of the American systems that were used to, if you're an American with me here, just trust that these things work. If you're not familiar with metric, it's going to work out just fine.

So, we have to take my weight and divided by 2.2. So, 167.7 divided by 2.2, and we come out to roughly 76.2 kilograms. Do that again, for my after workout weight 165.5 divided by 2.2, came out as 75.2 kilos. So, I lost in a somewhat coincidental about one kilo in my 45 minutes session. Now, we actually need to convert that to grams and then also know that we are doing our fluid in milliliters, use Google for conversion here because it's a really dumb conversion number. But I drank about 90 milliliters of fluid. So, adding those together, that thousand grams and the 90 milliliters, you can do that just trust the metric thing. 1,090 grams is roughly what I lost during my pool workout.

So, if we divide all of that by 45 minutes versus the amount of time I worked out, then I'd have lost about 24.2 milliliters per minute. If you didn't follow all that, the nice thing about video is you can go back and watch it again. But I will also have that equation down in the description so you can look at it and know how to do it by yourself, either watching me go through it again or just looking at the equation, plugging in the numbers and going along. If you’re an endurance athlete like me, it's probably more useful to think of sweat loss in terms of a rate per hour versus rate per minute because we can be going multiple hours a time.

That means taking our per minute rate multiplying by 60 and then converting those millimeters back in ounces, ?? 5:15> bottles. It's kind of annoying to do that because you gotta divide by 29.57. That's the annoying conversion since nothing seems to work nicely in all of the American systems we use. Go rebels for patriots, I guess. But once we do that with my numbers, then you figure out I lose about 49 fluid ounces an hour which is actually a lot, it's higher than average. The average athlete is going to sweat about 34 fluid ounces an hour.

So, it's important for me to take in fluid because of that. But before you get ahead of me, know that you can't absorb that much liquid an hour even if you're like me and you sweat a lot. So, subscribe to the channel, hit that button, the bottom right-hand corner, stay tuned. On my next video, I'm going to talk about over-hydrating and trying to figure out exactly how much water you should be drinking. So, stick around. I'll see you on the next episode of Runner’s High.