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by Sarah Koszyk RDN

April 4, 2023

These painful headaches can happen after an intense workout, including swimming

You’ve just had an extremely hard, intense swim and feel extra exhausted. Or maybe you’ve been swimming in a hot-weather environment, without adequately hydrating. After the workout, you start to feel fatigue and a throbbing pain in your head. You might be suffering from an exertion or exertional headache. 

Exertion Headaches

Exertion headaches occur after strenuous physical activity, and they can make it difficult for people to exercise at sufficient durations or intensities. People who are more prone to experiencing migraines can be more susceptible to exertion headaches.

This type of headache is exercise-induced, occurs after the workout, and is usually caused by intracranial pressure that builds during the activity. When exercising, muscles need more blood to circulate, which causes the blood vessels to dilate. When the muscles don’t get enough blood, a headache can occur as a result of the physical exertion. 

Swimmers can also experience headaches from the tightness of the goggles or cap on their scalp. Other factors that trigger exertion headaches are dehydration, extreme heat or cold, fatigue, hypoglycemia (not enough glycogen for fueling), insufficient warm-ups, and intense workouts. 

Tips to Prevent Exertion Headaches 

Stay Hydrated

 It’s not just about drinking a glass of water right before a swim. Hydration is a consistent practice in which you’re drinking water throughout the day to maintain adequate hydration levels. For intense swims, include a form of electrolytes to supplement the sweat loss. Swimmers sweat in the water and need to replenish their sodium and other electrolyte stores. 

The average male should drink about 3.7 liters (15.5 cups) of fluids daily, according to the US National Academies of Sciences, Engineering, and Medicine and reported by the Mayo Clinic. Women should be drinking about 2.7 liters (11.5 cups) of fluids daily. These recommendations include all fluids, such as coffee, juice, milk, soda, tea, and water, and fluids found in foods.

When you sweat, you should drink additional quantities of fluids, but this varies per individual. Bottom line is hydration is a first check-in if you’re experiencing exertion headaches. To prevent a headache, be consistent with your water intake. For long and intense workouts, consider adding additional fluids with electrolytes. For customized hydration needs, contact a Registered Dietitian Nutritionist to determine your specific fluid and electrolyte requirements.  

Fuel Consistently

Low blood sugar, or hypoglycemia, can also cause a headache after intense workouts. Glycogen, your body’s primary energy source, is needed for fueling. Carbohydrates provide glycogen. When your body doesn’t have enough energy for fuel, you can experience dizziness, shakiness, extreme hunger pains, blurry vision, excessive sweating, and headaches.

Eating a source of carbs consistently at the major meals and snacks can assist with maintaining adequate glycogen stores. Having a carbohydrate and protein combination snack or meal post-workout can also help replenish used glycogen stores and optimize muscle recovery. After an intense swim, enjoy avocado toast with eggs and tomatoes or a Greek yogurt parfait with berries, walnuts, and chia seeds. (For a great recipe, check out “Acorn Squash Stuffed with Quinoa and Chicken Sausage” from the November-December 2022 issue of SWIMMER.)

Get Adequate Sleep

Sleep is essential to overall health, wellness, and stamina. When you get regular, restful sleep, you function better, and you have more energy. If you try an intense workout when you’re already feeling fatigued, you won’t be able to push yourself as hard, which can hinder your performance and speed. Lack of sleep can also bring on an exercise-induced headache because your body is already struggling with blood flow and exhaustion. For tips on the best sleep practices, read the article “Better Sleep for a Better You” in the March-April 2023 issue of SWIMMER.) 

Warm Up Before Intense Workouts

A 2017 study published in US Pharmacist noted that athletes who warmed up for at least 15 minutes prior to an intense 45-minute workout had no worsening of migraines despite the extensive exercise. Properly warming up the body likely prevents exercise-induced headaches due to the increased blood circulation and flow within the muscles. Once the intensity of the exercise accelerates, the muscles are already primed and ready to go with the flow.

Supplement if needed: Food first, supplementation second. Supplements are there for people who have tried modifying their hydration, diet, sleep, and warm-ups. Refer to your primary care physician first for proper dosing and needs. Some supplements supported by research that have been suggested to assist with preventing exertion headaches include butterbur, CoQ10, feverfew, magnesium, and riboflavin.



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