Circadian Rhythm
Circadian rhythms are physical, mental, and behavioral changes that follow a daily cycle. These rhythms primarily respond to the amount of light and darkness in our environment, for example sleeping at night and being awake during the day. Circadian rhythms are found in most living things, including animals, plants, and even tiny microbes. The study of circadian rhythms is called chronobiology. Modern science has begun to study the very crucial role that circadian rhythm plays in people’s health. This includes how disruptions to circadian rhythm – environmental factors, lifestyles, irregular diet and sleep patterns – impact health. For example, there are indications that factors which cause disturbances of circadian rhythms may increase the incidence of diseases such as depression, cancer, cardiovascular disease and diabetes.[1]
Qi Gong experts and Chinese Medicine practitioners understood the subtleties of the daily circadian rhythm long ago and Western medicine has only recently begun to confirm things that have been common knowledge in China for over a millennium.
The Meridian Clock
Ancient Chinese physicians discovered that acupuncture meridians have their own very distinct circadian rhythms, and that these rhythms, if disrupted by extreme cosmological events, or by a lifestyle that is out of balance, could cause disease. They also found that acupuncture treatments could take advantage of this aspect of human chronobiology to increase the efficacy of acupuncture by needling points at certain times of the day. The timetable of the daily meridian cycle is laid out in the following diagram.
The Meridian Clock shows that each meridian has a time when it is most full of energy (Qi), before this peak moment subsides and moves on to the next meridian. This tidal flow moves through all the systems in the body, including the organs that connect to the meridians. Although all of the meridians have energy flowing through them all of the time, there is a discernible pattern of increase and decrease, waxing and waning, or a high tide and low tide, for each meridian that can be observed at any moment. For example, the Heart Meridian peaks (high tide) between 11 am and 1 pm and it is at its low tide when the Gallbladder Meridian peaks between 11 pm and 1 am. Between 11 pm and 1 am the heart should be at rest as blood and Qi flow back into the gallbladder and the liver.
Using the Meridian Clock for Optimum Health
Morning
At 5 am, there is a rising tide of Yang Qi, This is the perfect time to do Qi Gong and to stretch and move the body, ideally outside in nature so that the lungs can get fresh air and the sinews and muscles can extend outward. Breathing exercises and active exercises will have the maximum effect at this time because the energy of the Lungs has just peaked and is still expanding outward. The early morning before breakfast is a good time for active exercise. With Yang Qi on the rise, there is plenty of energy for exercise, which will also stimulate digestion and assimilation.
From 5-7 am the Qi of the Large Intestine peaks,so this is the perfect time to have a bowel movement and remove wastes so that the body is ready to take in nutrition between 7-9 am when the Qi of the Stomach reaches its peak. Drinking a cup of warm water can aid elimination. Breakfast should consist of warm and nourishing foods that will sustain the morning activities. Warm food is easy to digest and nourishing food allows one to have energy in the morning without pulling on one’s reserves. In China, breakfast often includes warm soups like congee or millet soup with pumpkin. In the West, oatmeal often serves a similar function of a nourishing fluid replenishing food,
From 9-11 am the Spleen is at its peak, distributing nourishment and fluids throughout the body. The San Jiao channel is at its low ebb at this time so it is best not to eat to many moisture producing foods or over-consume fluids as the San Jiao aids in regulating body fluids. Avoiding overthinking and rumination in the late morning can aid the the ability of the spleen to distribute nourishment and fluids.
Noon
Between 11 am and 1 pm the Qi of the Heart reaches its peak and then Yang Qi begins to recede, so it is good to take a short nap, brief rest or meditate after lunch (1 pm). It is best to eat a a moderate lunch without a lot of fatty foods, because the Gallbladder is at low tide and may not adequately supply bile. Try to eat between 12:30 and 1 pm, so that you finish when the Small Intestine peak (1 pm to 3 pm) is at high tide and ready to absorb nutrients.
Afternoon
From 1-3 pm is a good time to do lighter work so that the Small Intestine can absorb nutrition
Evening
From 5-7 pm is when the Kidneys reach their peak, particularly with regards to filtering blood and maintaining a proper chemical balance. This is a good time to have dinner to nourish the kidneys.
Pericardium Qi peaks between 7-9 pm. After eating, activate your circulation either by walking and stretching gently. It is also a good time to look at distant scenery, or chat quietly about unimportant things so that mind and body relax. Because Stomach Qi is at its low ebb at this time it is best not to eat a heavy meal for dinner.
From 9-11 pm Yin is peaking and the San Jiao (Triple Heater) Qi peaks. The San Jiao is the pivot of the body’s energy and metabolism, so it is essential to relax the body by reading quietly or perhaps watching TV, although it is best not to overtax the eyes so that the Liver (peaking from 1 am to 3 am) is relaxed. The Spleen is at its low tide, so it is better not to eat or snack at this time as the Spleen cannot properly transform food and fluids. Resting quietly and not eating help the body prepare for sleep.
Ideally by 11 pm one is asleep so that blood and Qi can begin to return to the Liver and Gallbladder and these organs can recharge. Between 11 pm and 1 am the Heart is at its lowest tide, so this is the chance for the heart to also rest.
Between 1- 3am Liver Qi is most active so it is very important that one sleeps deeply. This allows the Liver to recharge and clean the blood, and to process emotions, allowing one’s inner spirit to be calm and relaxed.
Summary
| Time | Meridian/Organ | Ideal Body Activity |
| 1-3 am | Liver | Deep Sleep and Dreams
Blood is Stored Recovery and Repair |
| 3-5 am | Lungs | Sleep
Preparation for Waking Qi is Distributed |
| 5-7 am | Large Intestine | Awaken
Meditate/Qi Gong Bowel Movement |
| 7-9 am | Stomach | Exercise
Breakfast Digest Food |
| 9-11 am | Spleen | Transform Food
Raise Clear Yang Brain is Active |
| 11am-1 pm | Heart | Yang Peaks
Blood Circulation is Active Lunchtime |
| 1-3 pm | Small Intestine | Food Absorption
Energy Levels Drop Good Time for a Nap |
| 3-5 pm | Bladder | Urination & Drink Water
Energy is Restored Good Time for Work |
| 5-7 pm | Kidney | Dinner (not too heavy)
Store Nutrients & Jing Good time to Relax |
| 7-9 pm | Pericardium | Sit Quietly & Rest the Eyes
Chat Quietly Stroll and Relax |
| 9-11 pm | San Jiao | Do Not Eat or Snack
Relaxing Activities |
| 11 pm–1 am | Gallbladder | Sleep
Recovery & Repair |
It is important to remember that this post outlines a perfect day of healthy behavior following the Meridian Clock. Use this as a guideline for healthy living and adapt it as necessary to your schedule. These are principles of healthy living that can greatly aid one’s energy and health. They are not written in stone and should not be taken as gospel
Notes
[1] “Circadian Rhythm, Lifestyle and Health: A Narrative Review.” Dariush Farhud and Zahra Aryan. Iran Journal of Public Health, 2018 Aug; 47(8): 1068–1076.
