Leg Day: The Exhausting Workout That Keeps You Awake

Many athletes experience sleep disturbances after a hard workout or race, despite feeling exhausted. This phenomenon is known as post-exercise insomnia and is characterised by difficulty falling or staying asleep, along with feelings of radiating heat and an elevated heart rate. While there isn't one simple cause, several factors contribute to this sleeplessness.

Exercise increases the heart rate, core temperature, and sweat rate. It also stimulates the nervous and endocrine systems, resulting in the release of stress hormones such as cortisol, norepinephrine, and adrenaline. These hormones can remain elevated for up to 48 hours after exhaustive exercise, disrupting the body's natural sleep-wake cycles. Additionally, dehydration and elevated body temperature after exercise can further hinder sleep.

To improve sleep after intense leg days, consider adjusting your caffeine intake, particularly close to bedtime. Implement a bedtime routine that includes cooling activities, such as cold showers or sleeping in a cool environment. Prioritise proper nutrition and hydration, as hypoglycemia and dehydration can worsen sleep disturbances. Finally, manage lifestyle stress through techniques like meditation and yoga, which can help counteract the negative effects of cortisol.

Restlessness in the legs

Restless legs syndrome (RLS) is a nervous system disorder that causes an overpowering urge to move your legs. It is also known as Willis-Ekbom disease, primary RLS, or idiopathic RLS. It is considered a sleep disorder because it usually happens or gets worse while you’re at rest. It is also a movement disorder.

RLS affects up to 10% of people in the U.S. and is more common in women. Middle-aged people are more likely to have severe symptoms. The symptoms range from mild to unbearable and usually affect both sides of the body. They can also happen on only one side, or they might start on one side and then move to the other.

The symptoms of RLS include unusual feelings in the legs (such as itching, crawling, pulling, aching, throbbing, or pins and needles) and a powerful urge to move the legs to make the sensations go away. The urge to move the legs is often accompanied by strange sensations and is triggered when one tries to relax or sleep. It can get worse if left untreated and, over time, a lack of sleep can cause problems at work or home.

There is no cure for RLS, but there are ways to manage the symptoms, including:

• Lifestyle changes: getting regular exercise, following a sleep schedule, and avoiding caffeine, alcohol, and tobacco.
• Physical treatments: using heating pads or ice packs on the legs.
• Medications: dopaminergic drugs, benzodiazepines, narcotic pain relievers, and anticonvulsant or anti-seizure drugs.
• Massage: studies have shown that massage can help improve RLS symptoms and quality of life.

Soreness and pain

• Body Core Temperature: During intense workouts, your body temperature rises as it works to dissipate heat and handle the physical stress. This elevated temperature can take several hours to return to normal, delaying sleep. To counteract this, try proactively cooling down your body after a workout. You can do this by using wet towels, cold showers, or air conditioning.
• Hormones: Intense exercises trigger the release of hormones such as cortisol, norepinephrine, and adrenaline. These hormones can increase your heart rate and keep your nervous system active long after your workout, making it difficult to relax and fall asleep. Managing your caffeine intake, especially close to bedtime, can help mitigate this issue as caffeine stimulates the central nervous system.
• Electrolyte Depletion and Dehydration: Intense exercises, especially in hot or humid conditions, can lead to the loss of electrolytes like sodium, potassium, and magnesium, which are crucial for muscle function and hydration balance. Failing to replenish these electrolytes can lead to muscle soreness and restlessness. Dehydration also plays a role as it makes it harder for your body to regulate temperature, blood pressure, and energy levels, resulting in restlessness and discomfort. Staying properly hydrated before, during, and after your workouts is essential for regulating body temperature and promoting sleep.
• Intensity and Timing of Exercise: The intensity and timing of your workouts can also impact your sleep. High-intensity exercises close to bedtime can disrupt your sleep due to the endorphins energizing your brain and the release of stress hormones. Try to exercise at least two hours before bedtime, as it typically takes a couple of hours for the effects of the workout to wear off. Additionally, 30 to 90 minutes after exercising, your body temperature drops, which can help you fall asleep more quickly and improve sleep quality.
• Rest and Recovery: Understanding your body's limits and giving it time to rest and recover is crucial. Pushing yourself beyond your limits can lead to overtraining, which can further disrupt your sleep. Listen to your body and adjust your workout intensity or duration if needed.
• Sleep Hygiene: Creating a conducive environment for sleep is essential. Keep your bedroom dark, quiet, and cool. Stick to a consistent sleep schedule and limit screen time before bed, as the blue light from electronic devices can interfere with your sleep.

High cortisol levels

Causes of High Cortisol Levels

• Stress: Acute, chronic, and traumatic stress can trigger the release of cortisol as part of the body's "fight-or-flight" response. Prolonged exposure to stress can lead to persistently high cortisol levels.
• Pituitary Gland Issues: The pituitary gland, often referred to as the "master gland," regulates the release of hormones, including ACTH, which stimulates the adrenal glands to produce cortisol. Conditions such as hyperpituitarism, benign pituitary tumors, and cancerous pituitary tumors can lead to overproduction of ACTH and subsequently high cortisol levels.
• Adrenal Gland Tumors: Adrenal glands, located above the kidneys, can develop benign or malignant tumors that secrete high levels of cortisol.
• Medication Side Effects: Certain medications, such as oral contraceptives and corticosteroids (e.g., prednisone, cortisone, methylprednisolone, dexamethasone), can increase cortisol levels when taken in high doses or for extended periods.

Symptoms of High Cortisol Levels

• Weight gain, especially around the midsection, upper back, and face.
• Fatty deposits between the shoulder blades.
• Wide, purple stretch marks on the abdomen.
• Muscle weakness in the upper arms and thighs.
• High blood sugar, potentially leading to Type 2 diabetes.
• High blood pressure.
• Excessive hair growth in people assigned female at birth.
• Weak bones and fractures.
• Difficulty concentrating.
• Irritability.
• Headaches.

Managing High Cortisol Levels

While medical treatment may be necessary for conditions like Cushing's syndrome, there are lifestyle changes that can help reduce cortisol levels:

• Improve Sleep Quality: Addressing sleep issues, such as insomnia or sleep apnea, can help lower cortisol levels.
• Regular Exercise: Engaging in regular physical activity can improve sleep quality, reduce stress, and lower cortisol levels over time.
• Stress Management: Learning to limit stress and adopting stress reduction techniques, such as deep breathing exercises, can help prevent and manage stress, thereby lowering cortisol levels.
• Laughter and Enjoyable Activities: Laughing and participating in fun activities promote the release of endorphins and suppress cortisol, leading to reduced stress and lower cortisol levels.
• Healthy Relationships: Maintaining positive relationships can reduce frequent stress and lower cortisol levels.

Intense workouts

Reasons for Insomnia after Intense Workouts

The timing and intensity of your workouts also play a role. Exercising too close to bedtime or engaging in high-intensity exercises within an hour of bedtime can disrupt your sleep. Caffeine consumption, especially late in the day, can further exacerbate the problem, as it stimulates the central nervous system and blocks chemicals that induce sleepiness.

Dehydration and electrolyte depletion are also often overlooked contributors to insomnia after intense workouts. Strenuous exercises in hot or humid conditions can lead to significant electrolyte loss, and failing to replenish these electrolytes can result in heightened restlessness and muscle soreness, making it challenging to fall asleep.

Remedies for Insomnia after Intense Workouts

• Caffeine Cut-off: Avoid caffeine late in the day, ideally setting a cut-off time of six hours before bedtime.
• Cool Down: Use fans, air conditioners, cool compresses, or bedding made of cooling materials to help lower your body temperature. Taking a hot bath before bed may also help by pulling blood away from the core, resulting in a decrease in core temperature.
• Nutrition and Stress Management: Focus on proper nutrition and stress management to modulate hormone levels. Hypoglycemia and caloric restriction increase cortisol and norepinephrine levels, so ensure you're adequately fuelled, especially during tough training blocks, and replenish glycogen stores before bed. Managing general stress levels through activities like meditation and yoga can also help counteract cortisol.
• Sleep Hygiene: Maintain good sleep hygiene by turning off screens before bedtime, keeping the bedroom dark and cool, and sticking to a consistent sleep schedule.
• Supplements: While long-term melatonin supplementation is not recommended, tart cherry juice is a natural way to increase melatonin levels and promote better sleep.
• Understand Workout Limits: Pushing your body past its limits can lead to insomnia. Tools like the Liipoo AbsolutSweat hydration biosensor can help you understand your body's boundaries and optimize your hydration and electrolyte replenishment strategy.
• Stretching and Relaxation: Give your body and mind a chance to relax with activities like stretching, meditation, or a light stroll.
• Exercise Timing: Experiment with different workout times to find what works best for you. Morning workouts can boost your energy and mood, afternoon workouts take advantage of peak body temperature and energy levels, while evening exercises may be preferable for night owls but can interfere with sleep.

Lack of a bedtime ritual

A bedtime ritual is a set of activities you perform in the same order every night, in the 30 to 60 minutes before going to bed. It can help create habits that tell your brain it is time to get ready for bed. Here are some tips to improve your bedtime ritual:

• Decide on a set bedtime: Your brain begins winding down for sleep a few hours before bedtime as part of your natural sleep-wake cycle. Decide on a bedtime and wake-up time and stick to them every day, including weekends. This helps train your brain to naturally feel tired at bedtime.
• Put away electronics: Electronic devices emit strong blue light, tricking your brain into thinking it is daytime and suppressing melatonin production. Put away electronics at the beginning of your bedtime routine and avoid using them in the evening as much as possible.
• Have a light snack or bedtime tea: Heavy meals and alcoholic beverages before bed can lead to indigestion and acid reflux. A light snack, like fruit or yogurt, and non-caffeinated herbal teas can calm your mind and induce sleep.
• Take a warm bath: Mimicking the nighttime drop in body temperature via a warm bath can trigger a sleepy reaction. Your body will heat up from the water and cool down quickly as the water evaporates, making you feel tired and relaxed.
• Listen to music: Music can be a powerful relaxation tool. Close your eyes, listen to the music, and let it turn your attention away from worries and anxiety.
• Stretch, breathe, and relax: Relaxation techniques like deep breathing exercises or progressive muscle relaxation can help release physical and mental tension. A few simple stretches or a massage before bed can prevent cramping and improve sleep quality.
• Write down a to-do list or journal: Many people find journaling restorative, and doing so in the evening helps sort out thoughts and feelings before bed. If journaling overwhelms you, consider starting with a simple to-do list. One study found that taking five minutes before bed to jot down tasks for the following days significantly sped up sleep onset.
• Prepare your bedroom: Make your bedroom a sleep oasis by setting the thermostat between 65 to 68 degrees Fahrenheit, turning off noisy electronics, dimming the lights, and putting things away. Enjoy your favorite scent with an aromatherapy diffuser.

Frequently asked questions