The Essential Guide to Hydration for runners
Hydration plays a pivotal role in an athlete's performance and overall well-being. Whether you're an amateur runner or a seasoned marathoner, understanding the importance of proper hydration is crucial. In this article, we'll delve into the science behind hydration, what happens during dehydration, and why it's essential for athletes to know their sweat rate and composition.
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runners’ HYDRATION: Everything you need to know
Hydration is the cornerstone of successful running. It affects nearly every aspect of your performance and well-being as a runner. Neglecting hydration can lead to decreased performance, discomfort, and potential health risks. Therefore, it's crucial for runners to prioritize hydration before, during, and after their runs to maximize their potential and maintain their health and safety.
the importance of hydration for runners & athletes
Hydration is incredibly important for runners for several key reasons:
1. Temperature Regulation: When you run, especially at high intensities or in hot weather, your body temperature increases. Sweating is your body's natural cooling mechanism. Adequate hydration ensures that your body can produce enough sweat to regulate your temperature and prevent overheating during a run.
2. Performance Optimization: Dehydration can significantly impact your running performance. Even mild dehydration can lead to a decrease in endurance, strength, and overall running efficiency. Maintaining proper hydration levels allows you to sustain your pace, run longer distances, and ultimately perform at your best.
3. Muscle Function and Cramp Prevention: Hydration is essential for muscle function. Dehydrated muscles are more prone to cramping, which can be painful and disrupt your run. Proper fluid balance helps prevent muscle cramps and allows for smoother, more comfortable running.
4. Heart Health: Dehydration can strain your cardiovascular system. When you're dehydrated, your blood volume decreases, making it harder for your heart to pump oxygen and nutrients to your muscles. This can lead to an increased heart rate and a higher perception of effort while running.
5. Joint Lubrication: Hydration also plays a role in joint health. Running puts stress on your joints, and dehydration can reduce the natural lubrication in your joints, potentially increasing the risk of joint injuries or discomfort.
6. Recovery: After a run, rehydrating is crucial for recovery. Proper hydration helps your body flush out waste products and replenish essential nutrients lost during exercise. It aids in reducing muscle soreness and expedites the recovery process, allowing you to bounce back quicker for your next run.
7. Cognitive Function: Running requires mental focus and concentration. Dehydration can impair cognitive function, leading to poor decision-making and coordination. Staying properly hydrated ensures that your mind remains sharp, allowing you to make split-second decisions during your run.
8. Prevention of Heat-Related Illnesses: Dehydration increases the risk of heat-related illnesses such as heat exhaustion and heatstroke, which can be life-threatening. Ensuring you are well-hydrated when running in hot conditions is vital for your safety.
The Science of Hydration
Water is the lifeblood of our bodies. It makes up 60-70% of our entire body, including a significant portion of our muscles, organs, and blood, and it's involved in almost every single physiological process in the body. The body uses water to perform essential functions, like regulating body temperature, cushioning and lubricating joints, maintaining blood volume and pressure, nourishing cells, carrying food through the body, and eliminating waste.
Every day we lose fluid via sweating, breathing, and urinating. But it's the sweating in particular that runners & athletes need to pay close attention to, because as soon as we start to run, we start to dehydrate. When we exercise, especially during intense activities like running, our body temperature rises, leading to increased sweating. Sweating is our body's way of cooling down, but it also means we're losing fluids and electrolytes, such as sodium, potassium, and magnesium. Approximately 75% of the energy we put into exercise is converted into heat and is then lost, which is why exercise makes us feel warmer. But that extra heat has to go somewhere to keep the body’s core temperate at a safe 98.6 degrees Farenheit, so our body sweats to keep cool. Our body temperature therefore rises if we become dehydrated since the body can’t produce enough sweat to keep cool, and this reduces our blood plasma volume. The results of dehydration can become very serious very fast and are explained further below.
the dangers of dehydration
Dehydration occurs when your body loses more fluids than it takes in. Even mild dehydration can have adverse effects on athletic performance. As you become dehydrated, your blood volume decreases, making it harder for your heart to pump blood to your muscles. Dehydration can have various symptoms, and for runners, it's essential to recognize these signs promptly to prevent performance declines or potential health risks.
Here's a list of common symptoms of dehydration for runners:
Increased Thirst: A strong sensation of thirst is often the initial sign of dehydration, indicating that your body is trying to signal the need for fluids.
Inability to Maintain Pace
Increased Perceived Effort
Decreased Performance or Endurance
GI Distress: stomach cramps, stomach sloshing, diarrhea, nausea, vomiting
Fatigue and Weakness: Dehydration can cause a drop in energy levels, making you feel tired and sluggish during your run.
Muscle Cramps: Dehydrated muscles are more prone to cramping, which can be painful and disrupt your running stride.
Dark Urine: Dark yellow or amber-colored urine is a clear indicator of dehydration. Ideally, your urine should be pale yellow to almost clear when adequately hydrated.
Decreased Urination
Dry Mouth and Dry Skin
Dizziness or Lightheadedness: This is related to the drop in blood pressure that dehydration may cause.
Headaches
Rapid Heart Rate: Dehydration can lead to increased heart rate due to the decrease in blood volume and the heart working overtime to pump blood to your extremities while you attempt to continue running.
Cognitive Impairments: Dehydration can affect your ability to think clearly, concentrate, and make decisions, which can be hazardous during a run.
Dark Circles Under the Eyes: Dehydration may lead to the appearance of dark circles or puffiness under your eyes.
Reduced Sweating: In severe cases of dehydration, you may notice a reduction in sweating, which is your body's natural cooling mechanism.
Heat-Related Illnesses: In extreme cases of dehydration, runners may be at risk of heat-related illnesses such as heat exhaustion, heatstroke, confusion, rapid breathing, and potentially life-threatening situations.
It's important for runners to stay vigilant and listen to their bodies. If you experience any of these symptoms while running, it's essential to stop, find shade or a cooler environment, and rehydrate immediately. Ignoring dehydration can lead to a decline in performance and pose health risks, so always prioritize proper hydration before, during, and after your runs.
Why Adequate Hydration While Running Is Crucial
If you’re not already convinced that adequate hydration is a non-negotiable - not only while on the run but in our daily lives - then allow me to drive the point home right now. As humans, we are only designed to deal with heat or limited water for a certain period of time, and these situations are stress states of mayday mode for the body, which often have prolonged adverse effects that go on far beyond the moments we are in them.
Running, in particular, places a significant demand on your body's hydration needs. When you run, you can lose anywhere from half a liter to several liters of sweat per HOUR, depending on factors like temperature, humidity, and your individual physiology. Failing to maintain proper hydration during a run can lead to any and all of the dangers of dehydration listed above. So, how do we avoid dehydration?
First, we need to understand our own, individual hydration needs.
Know Your Sweat Rate
To optimize your hydration strategy, it's crucial to know your sweat rate, which is how much you sweat per hour during exercise. Calculating your sweat rate involves weighing yourself before and after a run or exercise session to measure how much fluid you've lost. The difference in weight reflects the amount of sweat you've produced. By keeping track of your sweat rate under various conditions, you can tailor your hydration plan to meet your specific needs. This information helps you determine how much fluid you should consume during your runs and exercise sessions to stay properly hydrated.
Use our handy Sweat Rate Calculator below to input your measurements and find your sweat rate with the click of a button:
Understanding Your Sweat Composition
While knowing your sweat rate is essential, understanding your sweat composition takes your hydration strategy to the next level. Everyone's sweat contains a unique mix of electrolytes. Some individuals have sweat with higher concentrations of sodium, while others may lose more potassium or magnesium. Knowing your sweat composition can help you select the right sports drinks or electrolyte supplements to replenish the specific electrolytes your body loses during exercise.
The best way to gauge your Sweat Composition Rate is through a trusted wearable device. We recommend the Nix Hydration Biosensor as the best wearable sweat composition assessment tool on the market and use it ourselves. Use code LAURENC15 for $15 off a Hydration Biosensor, Half Training Bundle, or Full Training Bundle.
Final Thoughts: A Hydrated Future for Your Running Success
In summary, hydration is the cornerstone of successful running and athleticism. It affects nearly every aspect of your performance and well-being as a runner. Neglecting hydration can lead to decreased performance, discomfort, and some pretty scary potential health risks that are outlined above. But aside from these more pronounced symptoms, neglecting hydration is often the cause for those inconsistencies we experience in the way we feel, daily — in our energy levels, our ability to focus, our mood, how effortless & energetic we feel during those great running days versus on those off days where it feels like there are cement blocks tied to our feet and zero energy in the tank. We have control over making these moments more consistent, and that control lies in our ability to properly hydrate. Therefore, it's crucial for runners to prioritize hydration before, during, and after your runs to maximize your potential and maintain not only your health but to be able to sustain your sport as well.
If you need additional assistance in understanding your own hydration needs and creating a simple yet effective hydration strategy that works best for you, check out our different Nutrition for Runners programs. We also have an amazing Runners’ Fueling + Hydration eGuide that walks you through everything you need to know about proper hydration and fueling for your endurance training, race day, and recovery. As runners ourselves, our sports dietitians at Lauren Cornell Nutrition understand the challenges of hydrating from the trenches and are happy to guide you with expert advice. Stay thirsty, friends!