Photo: Pingora, Wind River Range, Wyoming. The 1200 foot Northeast Face route, one of the Fifty Classic Climbs of North America, ascends the middle of the face.

Awaking from a fitful sleep, I check the time, 1:30 am.  Wake up alarm coming in 90 minutes. It is mid-August 2009 in the Cirque of the Towers, Wind River Range, Wyoming. Laying back I knew sleep would prove elusive. Is this what my Viking ancestors felt before going to battle? Your body is preparing for the struggle ahead feeding your brain with a steady stream of growth hormone, testosterone, cortisol and adrenalin. These are the hormones that keep you alive. Do you feel increased awareness, scared, fearful, and anxious? Yes to all. Over the course of fifty one year’s climbing big routes, I have learned to accept the sleepless night before a big climb as a friend not an enemy. Lean into it and relax. Let your mind go. Focus on breathing.

The Alarm goes off. Time to go.

Photo: Halfway up the Northeast Face. Photo Credit: Paul Gardner

The Science of Sleep

It is estimated around a third of the population in the developed world have trouble sleeping. Some scientists believe over 30% of medical problems stem directly or indirectly from sleep disorders. Sleep impacts athletic performance and hormone production. Poor sleep is associated with anxiety, depression, dementia and premature aging. In this article, I look at how sleep affects our health and provide some thoughts on strategies to achieve optimal sleep.

Circadian rhythm is the natural, internal process that regulates our 24 hour sleep-wake cycle:                    

                9 pm:                     Melatonin release starts.

                2 am:                     Deep Sleep, maximum growth hormone release.

2 am to 4 am:     Lowest body temperature.

4 am to 6 am:     Peak cortisol level, rise in blood pressure.

6 am to 8 am:     Melatonin release stops.

8 am to 10 am:   Peak testosterone release, high alertness.

2 pm to 6 pm:    Best coordination, fastest reaction time, peak heart efficiency, and strength.

6 pm to 8 pm:    Highest body temperature and blood pressure

My climb played havoc with this cycle just as it did for my ancestors and for those caught in the stress of modern life.

The other process that regulates sleep is homeostatic drive: the normal accumulation of sleep debt which is a function of how long we stay awake. We sleep best when our sleep debt is high and our bodies are in sync with our biological clock. Regular bed and wake-up times are important because the body’s internal clock uses light signals to reset daily.

There are two states of sleep: Rapid Eye Movement, or REM sleep; and non-REM or deep sleep. Your deep sleep comprises 75% to 85% of your sleep and consists of four stages. In stage one, your brain organizes your 86 billion neurons as you drift into sleep. In stage two, burst of energy within the brain stimulate the cortex to preserve learned information—better memory retention. After this our heart rate slows, core temperature drops and we slip into the deep sleep of stage three and four. These stages are important for growth, healing, removing toxins and dealing with inflammation.

From stage four, we slip into REM sleep where most of our dreaming occurs. REM is governed by the limbic system, which governs our basic instincts and emotions. These cycles of alternating deep sleep and REM sleep repeat every 90 minutes. Anything that negatively impacts these cycles disrupts our sleep and sabotages our performance.

Sleep Deprivation and Disorders

Our ability to function and perform are directly and indirectly impacted by inadequate sleep. Sleep deprivation decreases our reaction times and increases our risk of injury. Sleep loss impairs judgement, decision making, motivation, focus, memory, and learning. Sleep optimization is critical for recovery from injury or surgery by reducing inflammation and stress. Better sleep combats anxiety and depression.

Poor sleep habits impact our hormones. Studies show sleep loss can result in testosterone levels of someone ten years older than normal. Testosterone is not only import for sexual function, muscle mass and strength, but it also has critical roles in memory and concentration. Deep sleep promotes the release of growth hormone needed for muscle growth and repair; and for bone building. Sleep deprivation can lead to high cortisol production causing muscle breakdown, increased stress and insomnia.

Sleep loss leads to premature aging. It is known to activate inflammation and cell damage. Independent studies have found an association between sleep loss and shortened telomeres. See my article: Lack of sleep increases your vulnerability to infections, cancer, heart disease, depression, diabetes, and dementia.

Evidence from epidemiological studies conclude the shorter you sleep, the shorter your life.

Promoting Good Sleep

First, you need to know if you have a problem. What is measured can be evaluated. Here are some recommended sleep assessment tools. Use the internet to find what works for you.

Athlete Sleep Screening Questionnaire (ASSQ)

Insomnia Severity Index (ISI)

Stanford Sleepiness Scale (SSS)

Epworth Sleepiness Scale (ESS) 

Pittsburgh Sleep Quality Index (PSQI)

STOP-BANG questionnaire for sleep apnea

If you think you have a problem see a doctor. It’s worth it.

Your bedroom is a good place to start looking for ways to improve your sleep.  How is your bed, sheets, pillow, and mattress? How is the temperature, air quality, light and humidity? All of these things can impact your sleep. If you are in a tent and the wind is cycling through like a freight train coming, there is not much you can change. Acceptance.

Regular exercise promotes good sleep. Your diet impacts your sleep. Tryptophan is needed to make serotonin, an important neurotransmitter for sleep. Sources of Tryptophan and Serotonin are found in high quality organic proteins. Consumptions of Kiwi fruit and tart cherries have been found to improve sleep. Alcohol, nicotine and caffeine before bed can disrupt sleep. Supplements zinc and magnesium have been found to aid sleep. I take both. I personally avoid all types of sleep medications. For me, they cause more problems than they solve.

One of the hardest things to control is a hyperactive mind at bedtime or upon waking in the middle of the night. With any case of arousal, active mind or anxiety, you enter the fight or flight mode. It is your survival response from your primitive brain fighting to keep you alive.  Relaxation techniques are key: mindfulness and meditation. “Trying to get to Sleep” does the opposite. Let go of the effort and relax your mind. Reject irrational thoughts and replace them with rational thoughts. What is the worst case? What are the probabilities that the worst case will happen? It has been my experience the worst case rarely, if ever, happens. Be a realist, be prepared and have a backup plan. You will sleep better.

Parting Thoughts

We head out trading warm sleeping bag for the pre-dawn cold. Our universe restricted to the circle of light shooting forth from our headlamps. My partner and I are in our own worlds of thought, fear and hope. I didn’t worry about getting much sleep. Having a poor night of sleep does not define the next day. We reached the base of the climb, the Northeast Buttress of Pingora at first light. We had the route to ourselves. We roped up and dove into the sea of vertical granite. Up we went for 1500 vertical feet; pitch after pitch of varied climbing on perfect rock under a cloudless blue sky. Nighttime fears of the unknown burned away by the August sun.  

Photo: On the summit of Pingora, August 2009. Photo credit: Paul Gardner

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