The effects of an acupressure sleep mask on light sleep, as measured by a wearable sleep-tracking device: a case study
Introduction
Since the introduction of wearable sleep tracking devices, consumers have enjoyed the advantage of detailed information about their sleep stages, and the benefits associated with each. For good reason, much attention is given to Stage 3 deep sleep and REM sleep.
It is during stage 3, for example, that physical recovery and tissue repair occur. The immune system is strengthened in stage 3 sleep, as well as long-term cognitive function. REM sleep is essential for memory consolidation and learning. It also aids in emotional regulation, mood enhancement and brain plasticity.
Light sleep, on the other hand, does not offer the restorative benefits of the other sleep stages, and for this reason, may garner less interest from consumers. Its importance to the overall quality of sleep, however, cannot be overstated.
The purpose of light sleep is to act as a bridge and prepare the body for deep and REM sleep. During light sleep, brain and muscle activity slow and breathing rate decreases, creating a relaxed state that facilitates transition to deeper sleep stages. Without sufficient light sleep, total sleep balance is disrupted, negatively affecting deep and REM sleep, and mitigating the physical, cognitive and mental benefits of those stages.
It is, therefore, beneficial to extend light sleep, in order to better prepare the body for deeper sleep, provided that its increase does not result in a loss of deep and REM sleep time. One potential mechanism for enhancing light sleep, is self-applied acupressure, in which mild, continuous pressure is applied to key acupoints on the body.
Studies have demonstrated a correlation between acupressure and sleep1, anxiety reduction3,4, stress reduction2, and relaxation2.
The purpose of this case study, therefore, was to determine the effects of a sleep mask incorporating EX-HN 3 (Yin Tang) acupressure, on the sleep stages of an individual using a wearable sleep-tracking device.
Background
The subject in this case study is a 46 year-old male with an active lifestyle and a passion for fitness. For more than 25 years, he has worked as a personal trainer and fitness coach, having begun an independent coaching business in 2017.
As an independent operator, he has a typical bi-modal weekday work schedule, from 6:00am until noon, and then again from 3:00pm until 7:00pm. He also sees clients from 7:00am until 2:00pm on Saturdays.
Although he works six days per week, he claims that his overall stress level has been relatively low, until recently. His daughter, born in 2018, is now approaching 7 years old, and is active longer and later into the evening, when the subject would customarily find time for relaxation and de-stressing. He claims that the long, busy days have caused an increase in stress, which has become somewhat of a concern.
According to the subject, while he would welcome more sleep, it’s not always possible, due to his early morning schedule and parenting time in the evenings. His interest, consequently, is primarily in his sleep quality.
Methods
The subject used an Apple watch for sleep tracking. He was provided a SOMO Sleep Fitness mask, which applies acupressure at the EX-HN 3 acupoint, located at the glabella, between the eyebrows. He was instructed on how to adjust the mask and was told to sleep with the mask each night, for one week, prior to recording sleep data. This period allowed for accommodation prior to data capture.
After the accommodation period, he used the mask nightly and recorded his sleep behavior for four weeks. He provided historical data for the month prior to wearing the mask, and then for the four weeks after the accommodation period. Criterion measures were total sleep time, core sleep time (light sleep), REM sleep, deep sleep, and respiration rate.
Results
Average sleep stage time and respiration, for the four weeks prior to and while sleeping with the SOMO sleep mask are presented in Figure 1.
Figure 1: Sleep stage and respiration data, with and without an acupressure sleep mask.
Sleep tracking data show that while wearing the sleep mask, versus sleeping without it, the subject experienced increases in total and core sleep times of 0:44 (13.8%) and 0:43 (22.6%) minutes, respectively, while deep and REM sleep times remained relatively unchanged. Respiration rate decreased by 1.4 (-11.0%) breaths per minute, after the subject began sleeping with the mask.
Discussion
The notable finding from this case study, was that the subject’s increase in total sleep time was primarily a function of a 0:43 minute increase in his core sleep stage. The benefits of enhanced core sleep are improved relaxation, stress reduction, and calm, leading into the restorative stages of deep and REM sleep. This improvement in relaxation is evident in an 11% reduction of his respiratory rate.
These changes come without a concomitant change in deep or REM sleep, suggesting that sleeping with an acupressure-based sleep mask can reduce stress and induce relaxation, while supporting recuperative deeper sleep.
References
1. Hmwe, N.T.T. (2016). Effectiveness of acupressure in promoting sleep quality: a systematic review of randomized trials. Holist. Nurs. Pract. 30(5): 283-293.
2. Honda, Y., Tsuda, A., Horiuchi, S. (2012). Effect of four-week self-administered acupressure intervention on perceived stress over the past month.
3. . Valiee, S., Bassampour, S.S., Nasrabadi, A.N., et.al. (2012). Effect of acupressure on preoperative anxiety: a clinical trial. Journal of PeriAnesthesia Nursing. 27(4): 259-266.
4. . Wang, S-M., Gaal, D., Maranets, I., et.al. (2005). Acupressure and preoperative anxiety: a pilot study. Anesthesia & Analgesia. 101(3): 666-669.
