Summer is here. It’s hot. It’s humid. And we’re all losing buckets of sweat every time we go for a workout. Even “easy” and recovery days are costing us lots of sweat. So how do we keep track of how much we need to hydrate, and how do we do it most effectively?
The first thing is to figure out how much water we’re actually losing during a workout. Even an easy recovery day is enough to get our heart rates up and the sweat pouring. And while this is more noticeable in the humid environments of the south and southeast, even the relatively drier environments of higher elevations and the west take their toll on our water reserves as well. True, sweating actually does something for you in the dried climates since it can actually evaporate, but that doesn’t mean that our body isn’t trying to cool itself off by sweating in the more humid reaches of the world. The best way to figure out how much water you’re losing is to weigh yourself before and after the workout. Each pound lost is 16 ounces of water lost, and it takes roughly 20 ounces to replace it (since not all of the water we use is lost as sweat).
Electrolytes are also lost when we sweat, which means that our bodies can’t actually hold onto as much water afterwards. The electrolytes we sweat out are also used for a variety of metabolic processes, on top of maintaining our ability to hold water inside our cells. This happens based on the concentration gradient of these electrolytes, or the relative concentration of them in our cells when compared to our bloodstream. If there is a higher concentration of electrolytes in our bloodstream than inside our cells, then water will flow out of the cells and the electrolytes will try to flow into the cells to balance it out.
This sounds great in theory but if we are down half a gallon of water or more (not uncommon after a workout in the summer), and we just try to replace it all with straight water, we’ll end up leaching all of the electrolytes we have left. The end result will be that the electrolyte balance can be restored/maintained, but we’re still dehydrated from a functional standpoint. We need to replenish those electrolytes as well if we want to actually hang onto any of that water. This doesn’t mean we need to snarf down a whole bag of tortilla chips after our run, but replacing some of those electrolytes will help us recover faster than not. This is why Gatorade was such a big breakthrough when it was first developed. It replenished an athlete’s electrolytes while also supplying the much needed water University of Florida athletes required to train and compete. This is the same reason why smart coaches and athletes purchase specific brands of bottled water. Some of them are pure water while others have just a smidgeon of salt added. Take a wild guess which ones smart coaches prefer.
Just like with injuries, prevention is worth more than rehabilitation. Getting pre-hydrated is key to being able to stay fully hydrated through a workout. This is especially true if we’re trying to do a quality workout that demands a high degree of effort. The other key dehydration prevention method is to continually take in water (and electrolytes) during the workout. For us endurance athletes this means we need to invest in handheld water bottles, water belts, or camelback hydration kits. Being able to ingest some fluid every 3-5 minutes makes it a lot easier to assimilate it than slamming 8-20 ounces every 20 minutes or so. This is especially important when we’re hot and more of our blood is going to our skin instead of our GI track, slowing down absorption. Ideally, we should be able to maintain our body weight over a workout if we’re proactive enough about pre-hydrating and continuously consuming fluid throughout the workout. Not only will we not get as dehydrated, we’ll be able to get more out of our workouts and improve more.
So be hydration-conscious out there this summer. Whether you’re in the soupy southeast or you’re high and dry in the mountains, keep those fluids coming. You’ll get more out of your workouts and you’ll recover faster from them if you stay on top of it. Hydrate. Exercise. Adapt. Rehydrate. And remember, #ItWillBeFun