Proper rest is important for anyone training in a progressive resistance training program, such as powerlifting and bodybuilding. The act of falling asleep shifts the body into a subconscious state of anabolism. Routine exercise does impact sleep patterns and the succeeding growth-stimulating events desired by bodybuilders. Adequate rest is required to optimize muscle recovery and growth.
As humans get older, sleep requirements decrease. During infancy, around 14 to 16 hours are spent asleep during the day. Toddlers often need around 10 to 13 hours per day. During teenage maturation and puberty, daily sleep hours are typically around eight to 10 hours per day – to wake up feeling rested. Adults typically need around seven to eight hours of rest. The elderly often find themselves needing less than seven hours per day. Throughout the human lifecycle, there is a relationship between sleep requirements and rapid periods of growth and development.
There are several stages encompassing a night’s rest. Most vividly recalled dreams occur during periods of rapid-eye movement. Non-REM sleep accounts for the majority of the time spent at rest; wherein the body transitions through four stages – one and two are considered light, three and four are thought as deep sleep. The body enters a heightened anabolic state during non-REM sleep, accentuating the growth and rejuvenation of the immune, nervous, skeletal and muscular systems. The endocrine glands of the hypothalamic-pituitary-gonadal and adrenal axes alter endogenous chemicals for growth and repair.
Slow-wave sleep encompasses the two deepest stages of non-REM rest – stages three and four. During this time, endogenous secretion of GH increases. In men, 60 to 70 percent of daily growth hormone secretion occurs during sleep. The adrenal hormone cortisol, responsible for breaking down proteins to produce energy, decreases during slow-wave sleep to promote protein synthesis. Even partial sleep depravation can result in an elevation of cortisol. It’s possible to increase slow-wave sleep through body heating (such as warm baths before bedtime), high-carbohydrate ingestion and intense exercise during the daytime hours.
In August 2000, the Journal of the American Medical Association published a study into the sleeping patterns of 149 healthy men, aged 16 to 83 years. The study was designed to determine age-related changes in sleep duration and quality, as well as sleep-induced alterations in GH and cortisol levels. They found the transition from early adulthood to midlife results in more time sent in light sleep (stages one and two) without significant changes in REM. A decline in slow-wave sleep from early adulthood to midlife was paralleled by a major decline in GH secretion. Hormonal balance is essential to metabolic efficiency. An earlier JAMA study demonstrated that exercise can benefit people complaining of sleep deprivation by improving sleep quality. A 2007 peer-reviewed journal by the American Academy of Family Physicians further supported the role of exercise by listing it as a treatment option for insomnia. According to the researchers, exercise improves sleep as effectively as benzodiazepines in some studies.
Occupational and social demands often position a person to obtain less nighttime rest. In the event of sleep loss, daytime napping can cause a beneficial change for the better. According to researchers at the Sleep Research Treatment Center at Penn State College of Medicine, a two-hour nap improves alertness and performance while reversing the negative effects of sleep loss on cortisol and interleukin-6 secretion, an immune system stimulator. In many cases, a nap can produce more beneficial actions in the athlete than training with the buzz obtained from stimulants, such as caffeine or ephedrine. Some studies have shown greater mental alertness after just 15 minutes of light sleep.
Anabolic steroids, prevalent in competitive bodybuilding, can disrupt sleep patterns by acting on an athlete’s central nervous system. High-dose AAS can raise nocturnal metabolic expenditure, leading to sleep fragmentation through the night. These substances can alter neural excitability through interaction with various neurotransmitters. They can interfere with serotonin and in so doing cause longer hours spent awake and reduced sleep efficiency. Increases of estradiol, the principle estrogen in the human body, are often reported in athletes using anabolic steroids. High concentrations of estrogen can further increase neurosteroid levels and down-regulate GABAA receptors, thereby boosting neural excitability and reducing sleep efficiency. GABAA receptors are the molecular target of the benzodiazepine class of tranquilizer drugs.
In November 2007, researchers from Brazil published an evaluation of sleep patterns and disorders of three groups: resistance-trained athletes using anabolic-androgenic steroids, trainees with no history of AAS use, as well as a sedentary group used as a control. They concluded that resistance training changes sleep patterns and architecture; moreover, supplementing with AAS causes further alterations. In the study, both groups of resistance-trained individuals showed a decrease in sleep efficiency with significantly more episodes of waking during rest. Additionally, administering supra physiological amounts of anabolic steroids resulted in even more interruptions during rest and less time spent in REM – which makes sense considering many anabolic events occur during non-REM. Although sleep duration was decreased for steroid users, their non-steroid using athletic counterparts spent less time in a stage four deep sleep. Despite the study finding a decrease in the percentage of time spent in REM, there are many anecdotal reports of lucid dreams while administering large amounts of anabolic steroids. Regardless of drug use, it’s likely that highly intensive training without sufficient recovery time between sessions may cause more interruptions during sleep. Since many athletic adults often report a need for less rest than their sedentary counterparts, it’s important to optimize daily life for greater sleep quality at night.
There are several variables to determine a athlete’s sleep requirements; even the time of day the rest occurs has a large influence on feeling rested and maintaining a person’s circadian rhythms. The goal for adults engaged in intense physical exercise is to obtain enough nighttime sleep so as to feel recharged upon waking. If not, a nap during the day can help restore physical performance and mental energy.
These brain waves, taken by electroencephalogram, are used by sleep experts to identify the stages of sleep. Close your eyes and your brain waves will look like the first band above, “relaxed wakefulness.” Theta waves indicate stage one sleep. Stage two sleep shows brief bursts of activity as sleep spindles and K-complex waves. Deep sleep is represented by large, slow delta waves (stages three and four). Lawrence Epstein, M.D., Improving Sleep: A Guide to a Good Night’s Rest, Harvard Health Publications 2007.
Eve Van Cauter, PhD; Rachel Leproult, MS; Laurence Plat, MD. Age-Related Changes in Slow Wave Sleep and REM Sleep and Relationship With Growth Hormone and Cortisol Levels in Healthy Men. JAMA. 2000;284:861-868.
A. C. King, R. F. Oman, G. S. Brassington, D. L. Bliwise and W. L. Haskell. Moderate-intensity exercise and self-rated quality of sleep in older adults. A randomized controlled trial. Division of Epidemiology, Department of Health Research and Policy, Stanford University School of Medicine, Calif., USA.
KALYANAKRISHNAN RAMAKRISHNAN, MD, and DEWEY C. SCHEID, MD, MPH. Treatment Options for Insomnia. University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma
A. N. Vgontzas, S. Pejovic, E. Zoumakis, H. M. Lin, E. O. Bixler, M. Basta, J. Fang, A. Sarrigiannidis, and G. P. Chrousos. Daytime napping after a night of sleep loss decreases sleepiness, improves performance, and causes beneficial changes in cortisol and interleukin-6 secretion. Am J Physiol Endocrinol Metab 292: E253-E261, 2007. First published August 29, 2006
Daniel Paulino Venâncio, Sergio Tufik, Silvério Aparecido Garbuio, Antonio Claudio Lucas da Nóbrega and Marco Túlio de Mello. Effects of anabolic androgenic steroids on sleep patterns of individuals practicing resistance exercise. European Journal of Applied Physiology. November 28, 2007
- Training frequency and supercompensation
- Overtraining and overreaching
- Exercise affects the immune system
- Concurrent training conditions
- Detraining: what happens if you stop exercising?