7 Reasons Running A Marathon Affects Sleep?

It's a popular belief that you should be tired after running a marathon and no sooner you hit the bed than you fall asleep. On the contrary, this is further from the truth, and most runners ask why they can’t sleep after a marathon.

If you are a regular runner, you might have encountered sleepless nights after long runs when training for a marathon. Let’s explore all angles.

Can’t Sleep Before a Marathon

If you can’t sleep as usual before a marathon, it can be because of nerves leading to the anticipated marathon. After all the intensive training, the race day finally arrives. Instead of worrying, take time and internalize your preparation.

Check that you know the route and anticipate the weather. Prepare mentally weeks before the marathon so that on the eve you can relax and get enough sleep. 

Can’t Sleep Before a Marathon

Can’t Sleep After a Marathon

After running 26.2 miles it’s hard to imagine that you would find trouble sleeping. But it’s a condition that affects many runners because they can’t stop their minds from replaying the events of the day.

Depending on the outcome of the marathon, you can be reliving happy moments or showing intense frustrations. But finishing a 42 Km race isn’t a simple feat and you should be proud of yourself.  

The adrenaline after running takes athletes hours to get over. But what happens if the sleeplessness takes more than days or weeks? What could be the problem?

Increased cortisol levels

Cortisol is also the body’s stress hormone as it is an indicator of the human body's response to external and internal stressors. Intensive running can trigger this stress hormone that acts on various body systems including:

·         Nervous

·         Immune

·         Cardiovascular

·         Respiratory

·         Reproductive

·         Musculoskeletal

·         Integumentary

The cortisol hormone is responsible for the sleep/wake cycle. In times of stress, it boosts your body with energy to make your body handle the situation. Running 26.2 miles can be stressful for the body.

Cortisol levels shift during the day but as you head to sleep you need lower levels. Why? Because cortisol also prevents the production of melatonin, a hormone necessary to induce natural sleep.

Adrenaline release

Most runners experience an adrenaline rush after a marathon. When in this state, your heart pumps faster and redirects the blood to where it’s required. The adrenal gland breaks down fats and glycogen in your body’s active muscles.

The intensity of the run determines how much of the adrenaline rush you will get.

According to a study by BBRA, the adrenaline rush can last between an hour and 48 hours to diminish completely. Running a marathon is intensive, and, naturally, your body will be under stress and produce adrenaline.  

Low-Calorie consumption

Running is among the best ways to burn calories. When training for a marathon you need to be on a healthy diet that includes replenishing the glycogen stores you burn during training.

Insufficient calories trigger a low sugar level and this makes your body release cortisol and adrenaline forcing you to stay awake. This is called the catatonic state.

At night, your body should be in the anabolic state that allows it to recover and repair damaged muscles and tissues. Don’t skip evening meals after long runs, and don’t go to bed hungry after a marathon.

Eat a banana or cottage cheese because such foods are easily digestible. 


Overtraining and lack of sleep are almost inseparable. It’s a vicious cycle that once you get on can be difficult to let go. Excess workouts and lack of sleep are guaranteed to lead to health complications.

Your body doesn’t recover or repair damaged muscles which might prompt injuries. If your body keeps producing cortisol and adrenaline because it's constantly under stress the result is insomnia.

New studies show that there’s a connection between injuries, illnesses, and sleep disorders among athletes who overtrain.


After running a marathon your fluid intake will be high. It’s expected so that the body can recover the lost energy. Dehydration is higher when running under warm weather and drinking isotonic fluids will replenish the electrolytes you lost running the marathon.

Even though hydration is a significant part of recovery, be sure not to drink lots of fluid in the evening as this will make your bladder full. Waking up frequently at night to empty your bladder affects your sleep pattern and might trigger insomnia.


High body temperature

Running a marathon will significantly raise your body temperature. If your body maintains a high temperature for several hours, it might affect your sleep. There’s no given time for your body temperature to cool after running a marathon. But there are ways you can help make it cool down faster without harming your body.

After running a marathon, consider cool drinks that can help to lower the temperature.

High body temperature

Caffeine intake

Caffeine and other caffeinated beverages are popular drinks for runners because they have stimulant properties that keep athletes active and alert. While these are useful qualities for a runner, the amount you consume over time will start to affect your sleep quality by diminishing it.

If you enjoy caffeine and find no reason to quit taking it because of its other benefits, at least change the time you consume it. Caffeinated beverages in the evening especially after long runs will keep you awake through the night.

Caffeine stays a couple of hours in the body and will hit peak levels between 30-40 minutes after consumption. Caffeine has a half-life rule. It means if you consume 400mg of caffeine, you will still have 200 mg in your system after five hours.

It takes over 10 hours to rid caffeine from your bloodstream.

Caffeine intake


If you can’t sleep after a marathon it is probably because your mind is still on the tracks while your body is at home trying to sleep. The Restless legs syndrome affects many athletes and this keeps them preoccupied with the day’s events.

But if the condition persists days or weeks after a marathon, you should consider seeing a medical expert for tips on better sleep practices.

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