Sleep and Athletic Performance
Young Ju, Ph.D.
Are you getting the right amount of uninterrupted sleep at the right time? Is a lack of good quality sleep interfering with your ability to perform at your best? If so, you are not alone. According to the National Heart, Lung, and Blood Institute (1), about 14-20% of Americans have sleep disorders, and about 33% of adults do not get enough sleep. Sleep quality is a critical physiological component of our health and wellbeing–as well as our athletic performance.
Circadian Rhythm and Sleep Cycle (2, 3, 4)
Sleep is a complex biological process which is regulated by the circadian rhythm and the sleep/wake cycle.
Circadian rhythm refers to the body’s internal clock that regulates the timing of physical, mental, and behavioral changes over a 24-hour period. For example, when it gets dark, melatonin (also called the sleep hormone) is released in the brain and promotes sleepiness.
The sleep cycle is a sequence of stages that recur during sleep. Typically, each cycle lasts about 90-120 minutes with 4-6 cycles per night. Physiological sleep repeats two main phases– NREM (non-rapid eye movement) stage and REM stage. Early in the night, the focus is more on deep NREM sleep, while later in the night, REM stages lengthen.
Non-REM sleep consists of three stages:
REM stage is crucial for brain function:
Factors Influencing Sleep (3, 4)
Sleep health is influenced by a range of biological, behavioral, environmental, and psychological factors.
Biological factors:
Circadian rhythm: Disruptions in circadian rhythm (e.g., jet lag, shift work) can affect sleep timing and quality.
Age: Newborns spend more time in REM sleep. The amount of deep sleep peaks in early childhood and continues to decrease with aging. Older adults often experience lighter and shorter sleep, because their circadian rhythm is changed and the production of sleep-regulating chemicals is reduced.
Hormones: Hormonal fluctuations, such as menstruation, pregnancy, or menopause can affect sleep.
Genetics: Certain sleep disorders are inherited conditions including narcolepsy (a neurological disorder that is characterized by excessive daytime sleepiness).
Behavioral factors:
Sleep schedule: An inconsistent sleep schedule can have negative effects.
Exercise: Regular physical activity can improve sleep quality, but vigorous exercise close to bedtime may interfere with falling asleep.
Diet: Heavy meals, caffeine, nicotine, alcohol close to bedtime can disrupt sleep.
Screen time: Using electronic devices before bedtime can delay falling asleep by reducing melatonin production.
Environmental factors:
Excessive light, uncomfortable room temperature, and noise can disturb sleep.
Psychological factors:
Stress, anxiety, depression, and mental disorders (e.g., attention-deficit/hyperactivity disorder, post-traumatic stress disorder, bipolar disorder) can disrupt sleep.
Health conditions and medications:
Health conditions: Chronic pain, sleep disorders (e.g., insomnia, sleep apnea, restless leg syndrome, and narcolepsy) can interfere with sleep.
Medications: Some medications (e.g., antidepressants, beta-blockers) can interfere with sleep.
Social and work factors:
Work schedule: Irregular work hours and shift work schedule disrupt the circadian rhythm.
Social obligations: family responsibilities, caregiving, and other social commitments can limit sleep.
Sleep and Exercise Performance
Sleep deficiency and poor-quality sleep can impair many aspects of physical and mental performance, injuries, and recovery.
The International Olympic Committee mental health document (5, 6) defined poor sleep health as insufficient sleep duration (less than 7 hours for adults), poor sleep quality, fatigue/sleepiness, irregular sleep schedule, and sleep disorders. These reviews found that poor sleep health conditions are more prevalent in athletes compared to non-athletes. Poor sleep conditions impaired athletic performance including:
Physical performance: Poor sleep can impair muscular strength and speed, lead to poor muscle recovery, and increase the risk of injuries.
Cognitive performance: Sleep helps clear waste from the brain. Poor sleep can impair decision-making, reaction time, vigilance, creativity, learning, and memory.
Mental health: Poor sleep can lead to mood changes and anxiety.
Immune system: Poor sleep can decrease your immune function, which can increase the chances of upper respiratory tract infections.
Pain perception: Poor sleep can alter pain perception, making training and competition feel more challenging.
According to a recent online survey study (7) conducted with current and former athletes (total 946 subjects) from all sports and competition levels in seven countries, sleep disorders are prevalent in both current (25.4%) and former (30.9%) athletes. This study also found that male athletes are less likely to seek professional help for their conditions than female athletes (8.4% vs. 26.2%).
The National Collegiate Athletics Association (NCAA) review (8) focused on sleep as an important aspect of health, performance, and mental functioning in collegiate athletes. The NCAA review also defines sleep health in terms of duration (at least 7 hours in adults), timing, quality, and absence of sleep disorders. This review identified academic, athletic, and social time demands as barriers to sleep.
You can analyze your sleep quality through The Pittsburgh Sleep Quality Index (PSQI). The PSQI is a widely used questionnaire which has been validated with a variety of clinical populations. (https://reference.medscape.com/calculator/603/pittsburgh-sleep-quality-index-psqi )
How to Improve Sleep Quality (9, 10, 11)
Although there are no standard treatment guidelines in primary care for sleep disorders, there are several ways to help get quality sleep.
A regular sleep schedule: A set of bedtime routines at same time each day can be helpful for preparing sleep. Long daytime naps (longer than 2 hours) can interfere with nighttime sleep.
A restful environment: Keep a cool, dark and quiet environment. Avoid screen time (such as cell phone, TV) before bedtime.
Regular exercise: Regular physical activity can promote the production of melatonin, which can help improve sleep quality and regulate circadian rhythm. Of course, exercise type, intensity, duration, and time hugely affect outcomes. Avoid vigorous exercise, training, or competitions 1-2 hours before bedtime because the core body temperature is raised thus requiring time to cool down.
Food: Avoid a big meal within 2-3 hours before bedtime. Both empty and full stomachs can be distracting. Avoid acidic fruits, spicy food, alcohol, and caffeine late in the evening.
Sleep medications: If lifestyle changes are not working, doctors may prescribe sleep medications. These drugs can help fall asleep faster and stay asleep longer, but they also can have side effects. Make sure to carefully follow the doctor's instructions.
Sleep Disorders (12)
Your sleep deficiency may be caused by a sleep disorder that can affect your physical and mental health, thinking, and daily functioning. Sleep disorders refer to conditions that disturb normal sleep patterns. There are more than 80 types. Some major types include:
Insomnia: the most common sleep disorder in which you are unable to fall asleep and stay asleep. It could be short-term lasting for a few weeks and long-term for 3 months or longer.
Sleep apnea: a breathing disorder which blocks the upper airway and stops breathing for 10 seconds or more during sleep. It’s associated with heart disease, stroke, type 2 diabetes, and obesity.
Restless leg syndrome: a tingling or prickly sensation in legs.
Hypersomnia: unable to stay awake during the day (e.g., narcolepsy)
Circadian rhythm disorders: problems with the sleep/wake cycle.
Parasomnia: unusual behaviors during sleep, such as walking, talking, or eating
Conclusion
Sleep is essential for overall health and wellbeing for everyone. Poor sleep can affect the ability to perform daily tasks and exercise performance. Chronic poor sleep may increase the risk of developing chronic diseases, cancer, neurodegenerative diseases, and mental disorders.
To start working to improve your sleep quality, consider doing an objective analysis of your sleep. Try the lifestyle changes recommended to improve sleep problems before they become chronic. For more information, see some of the links in the list of References. If lifestyle changes alone are not effective, please ask for help from health care professionals.
Dr. Young Ju is a Ph.D and Associate Professor of Human Nutrition, Foods, and Exercise at Virginia Tech.
References
National Heart, Lung, and Blood Institute. Sleep Health. https://www.nhlbi.nih.gov/health-topics/education-and-awareness/sleep-health
Reddy et al. National Library of Medicine: Physiology, Circadian Rhythm. Updated May 1, 2023. https://www.ncbi.nlm.nih.gov/books/NBK519507/#:~:text=The%20regulation%20of%20sleep%20is,light%20changes%20in%20our%20environment.
Sejbuk et al. Sleep quality: A narrative review on nutrition, stimulants, and physical activity as important factors. Nutrients. 2022, 14(9):1912.
Leeder et al. Sleep duration and quality in elite athletes measured using wristwatch actigraphy. J Sports Sci. 2012, 30(6):541.
Charest and Grandner. Sleep and athletic performance: Impacts on physical performance, mental performance, injury risk and recovery, and mental health. Sleep Med Clin. 2020, 15(1):41.
Reardon et al. Mental health in elite athletes: International Olympic Committee consensus statement (2019). Br J Sports Med. 2019, 53(11):667.
Montero et al. Self-reported prevalence of sleep and mental health disorders in current and former athletes: a preliminary cross-sectional investigation of help-seeking behaviors. Australian Psychologist. 2024, 59(5):464.
Kroshus et al. Wake up call for collegiate athlete sleep: narrative review and consensus recommendations from the NCAA Interassociation Task Force on Sleep and Wellness. Br J Sprots Med. 2019, 53(12):731
Harvard Health. 8 secrets to a good night’s sleep. https://www.health.harvard.edu/newsletter_article/8-secrets-to-a-good-nights-sleep
Mayo Clinic. Sleep tips: 6 steps to better sleep. https://www.mayoclinic.org/healthy-lifestyle/adult-health/in-depth/sleep/art-20048379
NIH News in Health. Good sleep for good health. Get the rest you need. https://newsinhealth.nih.gov/2021/04/good-sleep-good-health
National Library of Medicine. MedlinePlus. Sleep Disorders https://medlineplus.gov/sleepdisorders.html
This information is provided for your reference and you use at your own risk; you should rely on your medical professional for medical advice.
