Chiropractic Spinal Adjustments Have Positive Sleep Outcomes

By Mark Studin, DC, FPSC, FASBE(C), DAAPM

Seven hours of sleep is recommended by the American Academy of Sleep Medicine and the Sleep Research Society,[i] and over 25% of the population in the United States (85,000,000 people) does not meet these guidelines.[ii] Good sleep includes taking less time falling asleep and staying asleep.[iii] Considering a 30-day snapshot in 2020, the Centers for Disease Control (CDC), in a National Health Interview Survey, defined trouble falling asleep or staying asleep most days, and found that 14.5% of the population falls under that category.[iv] 

In the same study, the CDC also found that the percentage of adults who had trouble falling asleep decreased with increasing age from 15.5% among adults ages 18-44 to 12.1% among those aged 65 and over. Women (17.1%) were more likely to have trouble falling asleep than men (11.7%). Non-Hispanic white adults (15.1%) were most affected by sleep issues, followed by non-Hispanic black adults (14.3%) and non-Hispanic Asian adults (8.1%). They also reported that difficulties falling asleep increased as places of residence became more rural, from 12.7% in large central metropolitan areas to 171% in non-metropolitan areas.

According to Stanford University “While there's no precise number for the exact number of people addicted to sleep drugs, it's estimated that nearly 5 million people over 12 misused prescription sedatives like Ambien in 2022, with approximately 144,000 beginning this misuse for the first time, according to the National Survey on Drug Use and Health. Additionally, about 2.4 million people had a prescription sedative use disorder or tranquilizer use disorder, according to the same survey. About 6% of the U.S. population (20,400,000 people) has abused sedative-hypnotics.”[v]

The problem with sleep drugs is that they create a negative interconnecting cycle that deepens the problem. According to Valentino and Volkow (2020), “The neurobiology of sleep and substance abuse interconnects, such that alterations in one process have consequences for the other. Acute exposure to drugs of abuse disrupts sleep by affecting sleep latency, duration, and quality. With chronic administration, sleep disruption becomes more severe, and during abstinence, insomnia with a negative effect prevails, which drives drug craving and contributes to impulsivity and relapse. Sleep impairments associated with drug abuse also contribute to cognitive dysfunction in addicted individuals. Further, because sleep is important in memory consolidation and the process of extinction, sleep dysfunction might interfere with the learning of non-reinforced drug associations needed for recovery. Notably, current medication therapies for opioid, alcohol, or nicotine addiction do not reverse sleep dysfunctions, and this may be an obstacle to recovery. Whereas exposure to drugs of abuse is causal to sleep dysfunctions that further promote chronic use, sleep disorders in turn are risk factors for substance abuse, and their severity can predict the prognosis of substance use disorders.[vi] 

When studying the neurophysiology of a chiropractic spinal adjustment (CSA) and it’s relationship to sleep, mechanisms are critical. Therefore, one cannot be interchange a CSA with a physical therapy manipulation or mobilization, as the mechanism and neurobiochemical processes are different and render different results. The arbiter and ultimate test between the CSA and spinal manipulation is the central segmental motor control (CSMC) changes that occur as sequela to that treatment. The CSMC changes have been evidenced (a topic for another discussion) and are easily defined as central nervous system changes that affect the motor and other functions of the brain afferently. The core of the difference is where the thrust is directed. Haavik et al. (2021) reported, “It is possible to direct a thrust at any spinal segment, regardless of whether it is dysfunctional or not. Therefore, for the purposes of this review, if a thrust is directed at a spinal segment that has not been examined and identified as having clinical indicators of dysfunction, it will be referred to as spinal manipulation. In contrast, a thrust directed at a dysfunctional vertebral motion segment will be referred to as a spinal adjustment. This distinction is important, as adjustments are likely to have different physiological consequences compared to thrusting at or manipulating a vertebral segment that has no signs of motor control dysfunction.”[vii]

The key is determining the dysfunctional segments that make neuroplastic changes based on outcomes. In those dysfunctional segments, the high-velocity, low-amplitude thrust, or chiropractic spinal adjustment (CSA/HVLA) must be directed, or you will be manipulating and not realize the best outcomes. In determining outcomes, a CSA/HVLA thrust in deep abdominal muscular activation was 38.4% better than manipulation. Six months later, 19% of that additional muscular activation was retained. A CSA/HVLA thrust increased the H-Reflex and V-Wave (neurological feed to the central nervous system) by 16% without muscular fatigue. That control and manipulation group had no changes in amplitude, and the muscle fatigued much earlier. Maximum voluntary contractions of the jaw increased by 55% to 60% with CSA/HVLA thrusts only after one adjustment. Maximum voluntary contractions increased by 64.2% in chronic stroke survivors, with/HVLA only after one adjustment. A CSA/HVLA spinal adjustment increases motor evoked potentials by 54.5% in the upper limb and 44.6% in the lower limb muscles. A CSA/HVLA had a 16.76% change in the neurophysiological change in the 30N SEP (brain impulses). It changed brain functioning.[viii]^{,[ix],[x], [xi]} 

Haavik et. al (2024) performed neurophysiological assessments post-chiropractic spinal adjustments, which revealed, based on Electroencephalogram (EEG) and Somatosensory Evoked Potentials (SEPs), that Theta, Alpha, and Beta bands in the brain increased significantly, while Delta bands significantly decreased. They found this persisted when retested after 4 weeks. The control groups showed no changes.[xii]

Physiologically, Theta, Alpha, and Beta bands, among other things, promote sleep and deep relaxation, while Delta brainwaves, the slowest and deepest, are crucial for restorative sleep because they are associated with deep, dreamless sleep and the release of growth hormones. As sleep progresses, delta waves become less dominant, and faster brain waves (like theta and alpha) become more prominent.This equates to sleep better. 

Haavik also reported that it has long been known that a chiropractic spinal adjustment creates neuroplasticity (the brain's ability to change and adapt) in the primary somatosensory cortex, primary motor cortex, prefrontal cortex, and the cerebellum. All of these cortical regions directly affect the Default Mode Network, a system of interconnected brain areas that become more active when a person is not focused on external stimuli or engaged in a specific task, and is directly related to sleep.

Considering the side effects and negative neurological cascade of drugs used for sleeping by over 20,000,000 people in the United States, a chiropractic spinal adjustment can help many of those get to sleep and stay asleep.

[i] Consensus Conference Panel, Watson NF, Badr MS, Belenky G, Bliwise DL, Buxton OM, et al. Recommended amount of sleep for a healthy adult: A joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society. J Clin Sleep Med 11(6):591–2. 2015.

[ii] Adjaye-Gbewonyo D, Ng AE, Black LI. QuickStats: Percentage of adults aged ≥ 18 years who sleep < 7 hours on average in a 24-hour period, by sex and age group—National Health Interview Survey, United States, 2020. MMWR Morb Mortal Wkly Rep 71(10):393. 2022.

[iii] Ohayon M, Wickwire EM, Hirshkowitz M, Albert SM, Avidan A, Daly FJ, et al. National Sleep Foundation’s sleep quality recommendations: First report. Sleep Health 3(1):6–19. 2017.

[iv]Adjaye-Gbewonyo, Dzifa, Amanda E. Ng, and Lindsey I. Black. "Sleep difficulties in adults: United States, 2020." (2022).

[v] Waking up to sleeping pill risks (2020), Retrieved from: https://bewell.stanford.edu/waking-up-to-sleeping-pill-risks/

[vi]Valentino, Rita J., and Nora D. Volkow. "Drugs, sleep, and the addicted brain." Neuropsychopharmacology 45.1 (2020): 3-5.

[vii]  Haavik, Heidi, et al. "The contemporary model of vertebral column joint dysfunction and impact of high-velocity, low-amplitude controlled vertebral thrusts on neuromuscular function." European Journal of Applied Physiology 121.10 (2021): 2675-2720.

[viii] Haavik-Taylor H, Murphy B (2007b) Transient modulation of intracortical inhibition following spinal manipulation. Chiropractic J Australia 37:106

[ix] Haavik H, Niazi I, Jochumsen M, Sherwin D, Flavel S, Turker K (2017)Impact of spinal manipulation on cortical drive to upper and lower limb muscles. Brain Sci 7:2

[x] Marshall P, Murphy B (2006) The effect of sacroiliac joint manipulation on feed-forward activation times of the deep abdominal musculature. J Manipulative Physiol Ther 29:196–202

[xi] Haavik, Heidi, et al. "The contemporary model of vertebral column joint dysfunction and impact of high-velocity, low-amplitude controlled vertebral thrusts on neuromuscular function." European Journal of Applied Physiology 121.10 (2021): 2675-2720.

[xii] Haavik, Heidi, et al. "Neuroplastic Responses to Chiropractic Care: Broad Impacts on Pain, Mood, Sleep, and Quality of Life." Brain Sciences 14.11 (2024): 1124.