Sleep is an essential act that occurs to some extent in every organism. (source) It is characterized by both behavioral and physiological activities. Behaviorally, individuals in a sleep state experience limited mobility, slow eye movements, reduced responses to stimuli, impaired cognitive function, and a reversible unconscious state. Physiologically, sleep is characterized by specific electroencephalography (EEG), electrooculography (EOG), and electromyography (EMG) readings. (source)
Using these readings, sleep can be classified into sub-states: non-rapid eye movement sleep (NREMS) and rapid eye movement sleep (REMS). (source) Under normal conditions, individuals will cycle between these two phases of sleep for 90 minutes, four or five times per night. (source) Within NREMS alone, there are three stages – N1, N2, and N3 – that are each associated with various depths of sleep. (source)
The regulation of sleep is influenced by two main processes: circadian rhythms, which align with the day-night cycle, and homeostatic sleep drive, which increases the need for sleep as wakefulness extends. (source) These processes are controlled by the hypothalamus and pons within the brain. (source)
Sleep is a foundational pillar of performance that significantly influences both health and overall function. Sleep performance refers to sleep quality, duration, and efficiency. It also encompasses various aspects of sleep, including sleep architecture (i.e., the different stages of sleep), sleep continuity, and the body's ability to achieve restorative rest. The impact of sleep on overall functioning and cognitive and physical capabilities cannot be overstated.
Physical performance is heavily influenced by sleep performance. Sleep promotes the body’s ability to repair tissues, synthesize proteins, and release anabolic hormones, all of which are vital for recovery and adaptation. (source, source, source) Insufficient sleep can lead to a vast array of negative effects on physical processes. Decreases in sleep performance have been linked to decreased work capacity, power output, strength, and coordination, as well as increased risk of overtraining that leads to burnout and injuries during physical activities. (source, source, source, source, source, source)
Cognitive performance is highly influenced by sleep performance. Sleep has been shown to enhance motivation, memory consolidation, learning, and problem-solving abilities, while poor sleep performance can impair attention, decision-making, and reaction times. (source, source, source, source, source, source, source) Additionally, adequate sleep helps maintain emotional stability, which is crucial for managing stress. (source)
Sleep is vital for numerous functions, including memory consolidation, immune system support, and metabolic regulation. Disruptions in sleep patterns can lead to various health issues, highlighting the importance of understanding and prioritizing healthy sleep habits.
Immune function and inflammation status can also be influenced by sleep performance. (source) Adequate sleep performance is a crucial factor in supporting both of these systemic processes.
Common experiences associated with sleep performance are listed in the table below:
Incorporate tart cherry juice Tart cherry juice is touted for its ability to enhance sleep performance, as it contains high levels of natural melatonin, a hormone crucial for regulating sleep-wake cycles. Tart cherry juice is also rich in phytonutrients with antioxidant and anti-inflammatory properties that support optimal function of the brain and nervous system, promoting relaxation and deep, restorative sleep. (source, source) Recommendation Drink 8 oz of tart cherry juice nightly within an hour before bed
Limit screen time Limiting screen time is crucial for optimizing sleep performance, as excessive exposure to screens, such as smartphones and computers, disrupts the body's natural sleep-wake cycle. The blue light emitted by screens suppresses melatonin production, hindering the ability of the pineal gland to regulate sleep. (source, source) Recommendation Limit nonessential screen time to less than two hours per day and adjust screen settings to reduce eye strain when possible.
Supplement with Theanine Supplementing with theanine can enhance sleep performance by promoting relaxation and reducing stress, leading to improved function of the brain and nervous system. This amino acid supports the production of neurotransmitters like GABA, which play crucial roles in regulating sleep-wake cycles. (source, source, source) Recommendation Supplement with at least 200 mg of theanine daily
Sleep is a crucial activity that impacts every aspect of performance. By measuring related biomarkers and patterns, physiological readiness for optimal sleep can be better understood.
