Today I wanted to stay on the theme of fluid consumption, so let’s take a look at how to have fun and stay safe during the summer heat. This topic is important to me for many reasons. I am an Athletic Trainer which means I am a health care professional who collaborates with physicians to provide preventive services, emergency care, clinical diagnosis, therapeutic intervention and rehabilitation of injuries and medical conditions. So naturally, I want to keep everyone safe. In addition, I am a super heavy sweater, so I know firsthand the perils of not properly preparing. So let’s take a look at what you should be doing to keep yourself healthy and cool while exercising and looking hot!
Warm Up to The Heat
When it comes to exercising in the heat, you don’t want to go into it cold. And by that I mean, you need to get your body prepared for the extra stress that heat places upon it. Acclimation is the process by which the body adapts to heat stress, and it is a crucial element to heat safety. Because it can take a few weeks to get acclimated, you want to slowly increase the volume, duration, and intensity of your training. The complete process will vary depending on activity, but in general, during days 1-5 there should be light to moderate exercise lasting no more than 1 hour. During days 6-14, increase the exercise load up to 3 hours (1). This process is extremely important and should be taken seriously. It would also be wise to learn about the dangers of heat illness such as heat syncope, exercise (heat) exhaustion, and exertional heat stroke (2). Especially when you’re starting to get used to the heat, it is wise to prepare yourself by adjusting your training sessions, training with a partner, pre-cooling with ice towels before exercise. Try to and have ice vests/towels and even cold-water baths ready in case you need to rapidly cool down.
Sweet Scent of Sweat
Sweating is a normal, expected outcome of exercise. And before we talk about how much you should be drinking, it’s important to know how much you’re sweating. One way to figure this out is to use the simple test of weighing yourself before and after a run to get a sense of how much fluid you’re losing. This way you know how much water you need to be drinking during that time span.
But why do some people sweat more than others? Well, the answer might not be what you expect because it doesn’t have to do with how much body fat you have, or if you’re in great cardiovascular shape (3)! Sweating is a cooling mechanism that aims to dampen your skin. Then the sweat gets evaporated, and that process of evaporation cools you down. So essentially, those who produce more heat will be the ones who sweat more. Acclimation plays a role in this as well because as you exercise more in the heat, your body knows that you will be getting hot, so it starts producing a lot sweat quickly (4). There are other factors that play into how much you sweat. Factors you can’t change include how many sweat glands you’re born with (2 – 5 hundred thousand) and the fact that men sweat more than women (5). Modifiable factors that will make you sweat more include taking stimulants (e.g. caffeine), alcohol consumption, nicotine, and non-breathable clothing such as synthetic fabrics. There are also medical issues that will make you sweat more including hyperhidrosis and anxiety that require a doctor to diagnose.
Hydration, Electrolytes, Cramps, And Other Myths
When it comes to hydration during exercise, and life in general, there are a lot of myths, old wives’ tales, and misinformation thrown around on the internet. This is a bit off topic, but I would like to start by saying you don’t need to drink 8 glasses of water a day regardless of what marketing departments tell you (6). Even though dehydration will decrease your metal abilities, you would need to fight the urge to drink something for quite a while before that takes effect. Up next, coffee does not dehydrate you (7)!!!!!! Drinking coffee in isolation won’t cause dehydration because, guess what, it’s a liquid. The water that comes with the coffee far offsets the increase in sweating that comes with it. Here comes the big shock of the post… hydration and electrolytes have NOTHING to do with cramps during exercise (8)! This widespread misconception is again largely driven by marketing. Cramps are more likely caused by a high intensity of exercise, family history of cramps, and muscle damage (9). The latter point is the most important. Muscle damage caused by excessive heat can be a sign that your body is entering a danger zone. So when you’re exercising outdoors in hot and humid weather, take cramps seriously as a possible sign of heat illness (10).
Now that the myth busting is out of the way, let’s dive into what you should be doing to be safe in the heat. The first tip is to begin with the end in mind. And by that I mean you should come into an exercise session already hydrated. Euhydration is when you’re at an ideal, or slightly greater than ideal, level of hydration. This is important because many people can only drink about a liter of fluid an hour even though they sweat much more than that (11). So how can you tell if you’re at a euhydrated state? Well the answer is in your pee! Check out the chart below to see where your hydration level should be.
AM I HYDRATED? A URINE COLOR CHART
There are many hydration strategies out there, but your best bet is to just sip on water regularly throughout your exercise routine. If you don’t like the taste of water, then you can drink something with a little more flavor if you prefer. No matter what you drink, the end result will be about the same. But it’s important to remember that unless you are exercising for more than two hours, sports drinks aren’t going to be beneficial and will only add to your total amount of calories consumed for the day. The most important thing to do is weigh yourself before and after your exercise and drink back what you lost during that time.