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ISSN : 2693 6356 

2024 | Vol 7 | Issue 2 

 

 
 

 

  

 
 

Abstract Thousands of years of practice have gone into Qi Gong, a mind-and-body intervention for 

better health and relief from illness. An excellent research assessing the health benefits of Qi Gong 

has been impeded due to the absence of quantitative metrics for tracking the practice's quality and 

advancement.  

In order to create these numerical metrics, we used wearable sensors to track one person's vital 

signs while they meditated on Qi Gong for five years. 

Significant increases in blood oxygen saturation, pulse rate, respiration rate, and perfusion index 

were seen in this retrospective and exploratory investigation as a result of Qi Gong practice and 

physiological adaptation to its long-term training. Physiological alterations in vital signs include a 

noteworthy two-fold rise in the pulse-respiration rate ratio during Qi Gong meditation, compared to 

resting, sleeping, and moderate cycling circumstances, when the ratios remained at 4.  

 

In sum, this is the first report of its kind to cover a five-year longitudinal study. After they're proven 

in a well-planned cohort study, these simple, non-invasive vital signs can be used as biomarkers to 

measure how well people follow breathing control techniques when practicing Qi Gong. They can 

also be used to quantify the quality of Qi Gong practice in clinical trials that include Qi Gong 

intervention.  

 

 

Potential benefits of Qi Gong meditation in quantifiable physiology: A 

five-year longitudinal observation 

Ashlaey  

The U.S. Center for Chinese Medicine by Beijing University of Chinese Medicine, Rockville, 20850, USA 
 
 

 

 

 

 

 

 

 

 

 

1. usands of years of practice have gone into Qi 

Gong, a mind-and-body intervention for 

better health and relief from illness. An 

excellent research assessing the health 

benefits of Qi Gong has been impeded due to 

the absence of quantitative metrics for 

tracking the practice's quality and 

advancement.  

In order to create these numerical metrics, we 

used wearable sensors to track one person's 

vital signs while they meditated on Qi Gong 

for five years. 

Significant increases in blood oxygen 

saturation, pulse rate, respiration rate, and 

perfusion index were seen in this 

retrospective and exploratory investigation as 

a result of Qi Gong practice and 

physiological adaptation to its long-term 

training. Physiological alterations in vital 

signs include a noteworthy two-fold rise in 

the pulse-respiration rate ratio during Qi 

Gong meditation, compared to resting, 

sleeping, and moderate cycling 

circumstances, when the ratios remained at 4.  

 

In sum, this is the first report of its kind to 

cover a five-year longitudinal study. After 

they're proven in a well-planned cohort 

study, these simple, non-invasive vital signs 

can be used as biomarkers to measure how 



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well people follow breathing control 

techniques when practicing Qi Gong. They 

can also be used to quantify the quality of Qi 

Gong practice in clinical trials that include Qi 

Gong intervention.  

 

2. Introduction 
 

Breathing, mental and physical relaxation, and Qi 

Gong are the tenets of this ancient practice of 

meditation. Thousands of years ago, in the Yellow 

Emperor's Classic of Internal Medicine (Huang Di 

Nei Jing), a classic text of traditional Chinese 

medicine (TCM), it was observed that Qi Gong 

might improve health and prevent illnesses.1, 

Chapter 1 of this book indicates, "the sages were 

tran-quilly content in nothingness and the true 

vital forces accompanied them always; their vital 

(original) spirit was preserved within; thus, how 

could illness come to them?" This ancient text 

established a link between illness prevention and 

the practices of deep breathing and mental 

emptiness. It also linked the act of breathing with 

the vital spirit, or qi, in traditional Chinese 

medicine. Qi is the Chinese concept that 

differentiates between alive and dead things. 

Nevertheless, the connection to contemporary 

human anatomy and physiology remains unclear. 

From an energy metabolic point of view, oxygen 

is essential for human survival, because air 

contains oxygen. The role of oxygen in the 

synthesis of adenosine triphosphate (ATP), the 

biological energy currency, is a well-established 

fact in contemporary physiology. Life-giving ATP 

is synthesised from the chemical compound 

oxygen. The human body includes regulatory 

systems that detect when blood oxygen levels are 

low and react by increasing heart rate and 

breathing rate to restore blood flow, as oxygen is 

essential for survival. Important clinical markers 

for critical care patients to keep an eye on include 

blood oxygen level, heart rate, and breathing rate. 

Is it possible to utilise vital signs, which are well-

known for their significance, to track changes in 

blood oxygen utilisation and investigate how Qi 

Gong exercise enhances qi?  

Research on meditation has mostly taken the form 

of clinical trials and mechanistic investigations, in 

contrast to studies utilising Qi Gong. Meditating is 

a contemporary take on an old Buddhist practice. 

Similar to Qi Gong practice, several types of 

meditation include clearing one's thoughts, 

calming one's body, and breathing in a relaxed 

manner. Hence, the terms meditation and Qi Gong 

are considered synonymous throughout this piece. 

By 2021, over 300 clinical trials will have been 

published, and they may all be found by searching 

for "Qi Gong"2 or "meditation"3 on the the  

 

 

 

 

Research trial registry website (ClinicalTrial.gov). 

From 1973–2021, a search of PubMed for 

randomised controlled trials yielded 1,113 articles 

and 330 reviews. Publications on these subjects 

are on the rise, which may indicate that there are 

major initiatives to test this non-pharmaceutical 

intervention on human subjects. Among the many 

health benefits of Qi Gong and meditation 

described in these publications are its ability to 

lower blood pressure in hypertension patients 

(4,5), alleviate pain in cancer patients, and 

enhance their quality of life.6 For example, to 

determine if Qi Gong meditation reduced 

hypertension, researchers would monitor 

participants' blood pressure, one of the clinically 

significant illness variables utilised in studies 

aimed at treating or alleviating symptoms of 

disorders. In contrast to pharmaceutical clinical 

trials, which allow for easy monitoring of 

intervention adherence by direct medication 

administration to study participants, Qi Gong and 

meditation interventions are unique. So yet, there 

is no foolproof way to monitor how well one is 

doing with Qi Gong or meditation. Multiple 

reviews and meta-analyses on meditation 

intervention have pointed up the need for 

increased scientific rigour.7e9 There was a strong 

request to enhance methodological rigour, 

consistency, and follow-up over the long term.8 Is 



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it possible to quantify the quality and adherence of 

a meditation intervention by using vital signs?  

In recent years, wearable devices have emerged to facilitate 

the practice of meditation. For example, the MUSE, an 

electroenceph- alogram (EEG)-based biofeedback product, 

developed by Toronto- based company InteraXon,10 is 

commercially available to teach meditation by providing 

feedback based on EEG activity during meditation. Besides 

EEG, heart rate variability (HRV) has also been used as a 

biomarker for stress and applied in breathing therapy. It has 

been demonstrated that elongated breathing cycles can in- 

crease HRV resulting in stress relief.11 HeartMath Inner 

Balance, an HRV-based biofeedback product developed by 

HeartMath LLC,12 is also commercially available to assist in 

breathing exercise by providing real-time feedback based on 

HRV. Can these wearable devices be applied to Qi Gong 

practice to assess practice quality? 
With  the  intention  of  identifying  a wearable  device  to  
track 

physiological changes during Qi Gong practice, the author 

piloted using MUSE and HeartMath Inner Balance in Qi Gong 

practice and found that both devices were helpful for achieving 

and maintaining a meditative state. However, the results of the 

measures from both devices did not correlate well with the 

subjective experience of a high-or low-quality practice session. 

In addition, these 2 devices have not been widely accepted in 

clinical studies. To overcome these shortcomings, the author 

turned to easily accessible vital signs measured by the 

Microsoft Band, Apple Watch, and Masimo 

Material and methods 

 
2.1. Wearable devices 

 
Microsoft Band 2 (Microsoft Corp., Redmond, WA) and 

Apple Watch Series 3 or 4 (Apple Inc., Cupertino, CA) were 

used during Qi Gong practice sessions. The devices recorded 

and processed the data and transmitted the summary data to 

an iPhone through Bluetooth. Both devices provided 

summary and average data dur- ing each practice, including 

the duration of exercise, minimum and maximum heart rate, 

average heart rate, and calorie expenditure. Only the duration 

of exercise and average heart rate data were used in this 

analysis. Masimo oximeter MightySat (Masimo Corp., Irvine, 

CA)13 is a Food and Drug Administration (FDA)-approved 

medical device that was used to monitor vital signs before, 

during, and after Qi Gong meditation practice. The oximeter 

recording has a sam- pling rate of 1 recording per second. The 

MightySat oximeter out- puts 5 data types: pulse rate (beats 

per minute, bpm), respiration rate (breaths per minute, 

brpm) based on the plethysmographic waveform, oxygen 

saturation (SpO2, %), perfusion index, and pleth variability 

index (PVI).13 The perfusion index was calculated from 

oximeter plethysmography as the ratio of the pulsatile blood 

flow to the non-pulsatile blood in peripheral tissue. It has 

been demonstrated that the perfusion index is correlated 

with periph- 
eral vascular tone and can predict the incidence of 
hypotension 

during spinal anesthesia.14 The PVI was used to monitor 

variation in respiration and was not used in data analysis.15 

 
2.2. Qi Gong meditation practice 

 
A healthy female in her 50s without experience with Qi 

Gong practice started practicing Li Shaobo Zhenqi Yunxing Fa 

(LSBZQYXF) in 2015.16 In brief, the practice was performed in 

a sitting position, and the body was maintained in a fully 

relaxed posture. Minor attention was focused on the lower 

abdominal, lower Dantian region while maintaining a clear 

mind. Breathing was split into 2 phases: a normal inhalation 

phase and a prolonged exhalation phase. The exhalation was 

fully relaxed without forceful action with the qi sinking to the 

lower Dantian in the same expi- ration. Practices were 

performed daily with few exceptions. The LSBZQYXF was 

practiced 1610 times between June 2015 and December 

2020. The duration of each practice varied from 20 min to 2 h. 

The average duration of practice was 38.9 min, and the total 

practice time was 1044 h in this period. To reduce unforeseen 

factors  contributing  biases  to  the  recording,  such  as  

circadian rhythm or feeding effects, practices were done in 

fasting states 

MightySat oximeter.13 In this study, vital sign data collected 

over 5 years of Qi Gong practice were analyzed retrospectively 

to explore  

and assess the usefulness of vital signs as biomarkers for the 

physiological benefits of Qi Gong practice. The results indicated 

that the change in pulse-respiration ratio has the potential to be 

used to quantify the physiological state achieved during Qi Gong 

practice, which has not been reported in any prior longitudinal 

observations. In conjunction with blood oxygen saturation level, 

the pulse- respiration ratio also has the potential to be used to 

assess cardiorespiratory resilience. These findings provide 

objective measures to quantify adherence to slowed breathing 

during Qi Gong practice and to quantify its long-term training 

effects. The author hopes that once validated in a larger cohort, 

the pulse- respiration ratio, in combination with the blood 

oxygen satura- tion level, can be applied to improve human 

studies with Qi Gong interventions. 

Wearable device recordings 

 
Microsoft Band was used in 2016, and Apple Watch Series 

3 or 4 was used from 2017 to 2020. Both types of devices 

were placed on the left wrist. Data recorded and processed on 

the devices and the summary data were transmitted to an 

iPhone through the Blue- tooth. Recordings were conducted 

from the beginning to the end of each practice with these 

devices. A total of 982 recordings of the average pulse rate 

during the practice were collected from 2016 to 2020. 

Masimo oximeter MightySat was placed on the fourth 

finger of the left hand and connected to either an iPad or an 

iPhone through Bluetooth for data recording. Every oximeter 

recording had a before-resting control, meditation practice, 

and after-meditation 
 



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control. In 2016, the resting controls, before and after practice, 

were recorded for 3 min. However, preliminary analysis 

revealed that vital signs did not return to a resting level 3 min 

after practice. Thus, from mid-2017 to the end of 2020, the 

before-resting controls were adjusted to 5 min, and the after-

meditation controls were extended to 10 min. A total of 138 

oximeter recordings were collected and used in this study. 

 
 

2.3. Data processing and analyses 

 
The MightySat oximeter data were evaluated by plots of the 

raw recordings to visually check the quality of the recording. 

The pulse- respiration rate (PR/RR) ratio was calculated by 

dividing the pulse rate by the respiration rate. To combine the 

MightySat oximeter data collected from 2016 to 2020, the 

after-meditation control data were trimmed to the last 3 min. 

Oximeter recordings of each practice were selected as follows: 

(1) the first 5 s of the before- resting control were removed to 

avoid starting variations; (2) the last 10 s of meditation data 

were trimmed out from practice data points to remove noise 

generated by taking note of the ending time; (3) only the last 3 

min of after-meditation control were selected, excluding the 

last 10 s to avoid noise. Statistical analysis of oximeter data was 

performed only on the selected data. 
Data were analyzed with the open-source statistical 
software R 

(Statistical Computing, Vienna, Austria)17 and RStudio 

(RStudio PBC, Boston, MA).18 The ggplot package (ggplot2) in 

R was used for data visualization.19 The summary and average 

data collected with the Microsoft Band and Apple Watch were 

collected in Microsoft Spreadsheet and imported into R for 

analyses. On the dates when only the oximeter recordings 

were available, average pulse rates of those dates were 

computed from the oximeter data. The average pulse rates 

during meditation practices were analyzed. The nor- mally 

distributions of average pulse rate data are presented as violin 

plots. To evaluate the significance of changes, the Student's t- 

test package (t test) in R was used to perform a two-sided test 

at a 95% confidence level. 

Results 

 
2.4. Typical MightySat recordings of Qi Gong practice 

 
Three typical tracings from the MightySat oximeter 

recordings are shown in Figs. 1e3. Figs. 1A, 2A and 3A 

showcase the raw data of SpO2, pulse rate, respiration rate, 

perfusion index, and PVI. Figs. 1B, 2B and 3B depict the PR/RR 

ratios computed from the instanta- neous pulse and 

respiration rates shown in Figs. 1A, 2A and 3A. A typical Qi 

Gong practice tracing in Fig. 1B shows an increase in the 

PR/RR ratio during practice compared with before and after 

con- trols. Fig. 2B shows a raw data tracing from a practice 

that had a period of sleepiness noted in the practice note. 

During the sleepi- ness period, the PR/RR ratio dropped to 

the resting control level. A similar phenomenon was observed 

in separate recordings done under the sleep condition (the 

result not shown here). This feature presents a potential 

application of the PR/RR ratio to assess the quality of a Qi 

Gong practice by monitoring the adherence to pro- longed 

exhalation. Fig. 3B shows the PR/RR ratio during a mild 

cycling exercise. Small PR/RR ratio fluctuations occurred at 

the beginning and the end of the cycling. During cycling, the 

PR/RR ratio remained at a similar level to before and after 

control condi- tions. Different from resting controls, the pulse 

and respiration rates were significantly elevated 

simultaneously during cycling, as shown in Fig. 3A. To further 

evaluate the dynamic correlations between pulse rate, 

respiration rate, and SpO2, the raw data were broken into 5-

min segments. The means and standard deviations (SD) of 5-

min segments are plotted in panels C, D, and E of Figs. 1e3. As 

shown in Fig. 1C and D, pulse rates were increased when SpO2 

dropped  during  Qi  Gong  meditation   practice.   As   shown   

in Fig. 3CeE, pulse rate was again negatively correlated with 

SpO2. As shown in Fig. 3C and E, the pulse rate was positively 

correlated with the respiration rate during mild cycling 

exercise. By contrast, during Qi Gong meditation practice, the 

respiration rate was maintained at a slow rate, as shown in 

Fig. 1E. In agreement with known physi- ology, the intended 

action of slowing the respiration rate during meditation 

resulted in reduction of SpO2, which in turn triggered 

 
 



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Fig. 1. Oximeter recording of a single Qi Gong meditation practice. 

Notes: A: A typical recording output from a meditation practice. The red arrows indicate the start and the end of the meditat ion practice. Five data types were reported by a Masimo 

oximeter, MightySat: SpO2, pulse rate, respiration rate, perfusion index, and PVI. B: The PR/RR ratio showed a significant increase during meditation practice. C: Segmented 

statistics of pulse rate during the practice. D: Segmented statistics of oxygen saturation during the practice. E: Segmented statistics of respiration rate  during  the  practice.  C,  D,  and  

E summarize statistics of 5-min segments of A. C shows a slight increase in pulse rate that is negatively correlated  with the slight  drop (about 1%) in SpO2 shown in  D. E  shows a 

decrease in respiration rate during meditation practice. SpO2: oxygen saturation; PVI: pleth variability index; PR/RR: pulse-respiration rate ratio. 

 

 
 

 
 
 
 
 
 

Fig. 2. Typical Qi Gong meditation recording with poor quality. 

Notes: A: An example of a recording output of a meditation practice that is of poor quality. The red arrows indicate the start and the end of the meditation practice. The blue 

bar indicates a period of sleepiness noted in the practice notes about 20 min after the start of meditation practice. B: The PR/R R ratio showed a significant drop during the 

time of sleepiness noted during meditation practice. C: Segmented statistics of pulse rate during the practice. D: Segmented statistics of oxygen saturation during the practice. E: 

Segmented statistics of respiration rate during the practice. C, D, and E summarize statistics of 5-min segments of A. During the sleepiness phase from 25 to 40 min of 

meditation practice, the pulse rate decreased (C), SpO2 increased toward the resting level (D), and the respiration rate increased (E). SpO2: oxygen saturation; PVI: pleth 

variability index; PR/RR: pulse- respiration rate ratio. 

 



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Fig. 3. Oximeter recording of a mild cycling exercise. 

Notes: Cycling in seated position took place between the red arrows. A: Five measures resulted from the oximeter recording. The onset of increased pulse rate was correlated 

with the beginning of a mild cycling exercise. B: The PR/RR ratio did not increase significantly during mild cycling. C: Segmented statistics of pulse rate during the practice. D: 

Segmented statistics of oxygen saturation during the practice.  E:  Segmented  statistics  of  respiration  rate  during  the  practice.  C,  D,  and  E  summarize  statistics  of  5-min  

segments  of  A. Means ± SDs are shown in red. When the SpO2 shown in (D) was maintained at around 97%, the pulse rate (C) and respiration rate (E) increased proportionally, 

which resulted in the PR/RR ratios being maintained below 5. SpO2: oxygen saturation; PVI: pleth variability index; PR/RR: pulse-respiration rate ratio. 

 

the increase of pulse rate and PR/RR ratio. As shown in Figs. 1 and 3, the increase of the PR/RR ratio is a unique measure to demonstrate the 

difference between Qi Gong meditation practice and mild cycling exercise. 

 
2.5. Summary statistics of instantaneous recording data of Qi Gong practice 

 
Recordings of 138 practices with 420 508 data points were used to evaluate distributions, and the summary statistics of vital signs as 

well as the PR/RR ratio. The results are shown in Fig. 4. The violin plots indicate the distribution patterns of data points, and the box plots 

show the results of summary statistics, in which the red dots indicate the mean values, and the red lines show the standard deviation 

(SD). The summary statistics are also listed in Supplemental Table 1. In comparison with before and after controls, Qi Gong meditation 

shifted the pulse rate higher by 2 bpm on average  (before  meditation  51.3  ± 3.9  bpm,  during  meditation 

53.7 ± 3.6 bpm, and after meditation 52.7 ± 3.8 bpm), as shown in 

Fig. 4A. The respiration rate was decreased by 5.5 brpm on average (before meditation 13.0 ± 2.0 brpm, during meditation 7.5 ± 2.5 

brpm, and after meditation 12.5 ± 2.1 brpm), as shown in Fig

. 4B. 



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Fig. 4.  Distributions and summary statistics of vital sign data and the PR/RR 
ratio. 

Notes: Distributions of vital signs recorded with the MightySat oximeter are 

presented here in violin plots. Summary statistics are presented as box plots, 

where red dots represent means and red lines represent SDs. PR/RR: pulse-

respiration rate ratio. 

 

SpO2  was  decreased  by  0.4%  on  average  (before   meditation 

98.4% ± 0.8%, during meditation 98.0% ± 0.8%, and after 

meditation 

98.2% ± 0.7%), as shown in Fig. 4C. The PR/RR ratio increased 

nearly 2-fold (before meditation 4.1 ± 1.0, during meditation 7.9 

± 2.4, and after meditation 4.4 ± 1.1), as shown in Fig. 4D. The 

changes be- tween Qi Gong meditation and before or after 

controls were all significant (P < .001). Among the changes, the 

mean PR/RR ratio of 

7.9 in the Qi Gong meditation condition has not been reported 

before. This finding can be used as a quantitative measure to 

explore the physiological mechanism of Qi Gong meditation. 

Fig. 5 shows the non-linear correlations among the 

instanta- neous vital sign data in response to Qi Gong 

meditation training. To illustrate the progressive adaptation in 

long-term Qi Gong medi- tation training, the mean values 

grouped by years were graphically presented. The mean values 

of data collected in 2016 and 2020 are depicted in Fig. 5, and 

the same data collected in 5 years are shown in Supplemental 

Fig. 1. The left side of Fig. 5 (5A, 5C, 5E, 5G, 5I, and 5K) shows 

the mean data of resting control collected immediately prior to 

the meditation practice. The right side of Fig. 5 (5B, 5D, 5F, 5H, 

5J, and 5L) shows the mean data during Qi Gong meditation 

practice. In Fig. 5A and C, the PR/RR ratio before resting control 

was between 3 and 6 in 2016 and was expanded to 3e13 in 

2020, indicating a more flexible cardiorespiratory coupling 

under the resting condition after years of Qi Gong  meditation  

training.  In Fig. 5E, respiration rates increased to 16 brpm when 

pulse rates >65 bpm in 2016 but were maintained around 13 

brpm in 2020, which demonstrates the increased resilience in 

pulse-respiration regula- tion under the resting condition. This 

small change was achieved gradually starting in 2017, as 

shown in Supplemental Fig. 1E. As shown in Fig. 5K, the 

resting SpO2 level corresponded to the lower perfusion index 

curve in 2020 than in 2016, which indicates an adaption 

achieved with long-term Qi Gong meditation training. As 

shown in Fig. 5B, J, and L, the correlations between SpO2 and the 

PR/ RR ratio, pulse rate, and perfusion index shifted downward 

from 2016 to 2020 during Qi Gong meditation practice, which 

reflects a reduction in responses to the decrease of SpO2 level 

during Qi Gong meditation. As shown in Fig. 5D, the perfusion 

index was relatively similar between 2016 and 2020 when 

PR/RR ratios <10. When PR/ RR ratios >10, the perfusion 

index values in 2016 varied by 7 units (2e9 units), and they 

only varied by 4 units (5e9 units) in 2020. Fig. 5F, H, and J 

highlights the potential physiological mechanisms to maintain 

the stable perfusion index shown in Fig. 5D. As shown in Fig. 

5F, when pulse rates were between 43 and 53 bmp, the 

respiration rate was negatively correlated with pulse rate, and 

a significant reduction was evident in 2020. When the pulse 

rate was over 65 bmp, the respiration rate was positively 

correlated with the pulse rate. In 2016, the correlation between 

the respiration rate and pulse rate was a reversed bell shape 

and had significantly more volatility when the pulse rate was 

over 65 bmp. As shown in Fig. 5H and J, a pulse rate over 65 

bmp was a critical turning point for the regulation of the 

perfusion index and blood oxygen saturation. When the pulse 

rate was over 65 bmp, the perfusion index was decreased 

dramatically, and the SpO2 was highly variable. In 2020, the 

turning point of the sharp drop in the perfusion index was 

shifted to a higher pulse rate (about 2e3 bmp), and the 

amplitudes of the variabilities of SpO2 and pulse rate curves 

were smaller, indicating the adaptations of long-term training. 

Fig. 5L shows the downward shift of the correlation curve 

between SpO2 and the perfusion index during Qi Gong 

meditation practice in 2020, which suggests that the same 

vascular tone could tolerate lower levels of SpO2 in 2020 than 

in 2016 during Qi Gong meditation. To illustrate the 

progression of these changes, the data from 2016 to 2020 

were plotted in Supplemental Fig. 1. These changes were 

achieved gradually over the years of practice. Therefore, they 

could be true training effects. According to the existing 

knowledge of human physiology, these correlated changes 

indicate the training effects of Qi Gong meditation on the 

reduction of response amplitudes to moderate physiological 

hypoxia. 

Training adaptation was also demonstrated in Fig. 6. With a 

total of 1047 recorded pulse rates from the Microsoft Band 

or Apple 

 

 
 
 
 
 
 
 



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Fig. 5. Correlations among pulse rate, respiration rate, perfusion index, SpO2, and PR/RR ratio before-meditation control and meditation conditions. 

Notes: Mean values of the instantaneous pulse rate, respiration rate, perfusion index, SpO2, and PR/RR ratio collected in 2016 and 2020 are represented by the solid lines. The data 

of the before-meditation control are plotted in A, C, E, G, I, and K, indicating correlations among vital signs during the baseline and ada ption states achieved by long-term Qi 

Gong meditation practice. The data of Qi Gong meditation are graphed in B, D, F, H, J,  and L, indicating correlations among vital signs during Qi Gong meditation practice. SpO2: 

oxygen saturation; PVI: pleth variability index; PR/RR: pulse-respiration rate ratio. 



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¼ 

¼ 

Z  
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fig. 6. Average pulse rates during Qi Gong meditation practice are summarized 

over time. 

Notes: Violin plots demonstrate the distributions of average pulse rates of 

meditation practice. The box plot indicates the median value and first and third 

quartiles. Red dots and lines indicate the means ± SDs. Black arrow lines indicate 

the t test comparisons. 

***P < .001. Years of Qi Gong meditation training decreased the average pulse 

rate from 56 ± 3.6 bpm in 2016 to 53 ± 3.3 bpm in 2020. 

Watch during Qi Gong meditation practices (n  982) and calcu- 

lated from MightySat data (n 65), the average pulse rates of Qi 

Gong meditation practices dropped significantly (P < .001) 

from 

56.0 ± 3.6 bpm in 2016 to 53.0 ± 3.3 bpm in 2020. The violin 

plots in Fig. 6 demonstrate the distributions of average pulse 

rates. The boxplots indicate the summary statistics, where red 

dots and lines indicated the means ± SDs of average pulse rates 

grouped by years. Mean and SD data supporting Fig. 6 are 

shown in Supplemental Table 2. 

 
2.6. Limitation of algorithm-based respiration rate 

prediction by MightySat 

 
It was reported that the respiration rate extracted from 

plethysmographic waveform has its limitation beyond the 

range of 12e20 brpm.20 This limitation was also observed in 

the MightySat oximeter data reported in this study. Among the 

138 recorded practices, 40 of them (29%) also had the total 

breath counts during meditation detailed. Fig. 7 presents the 

correlation of average respiration rates between algorithm-

based and mentally counted rates. The average respiration 

rates of 40 counted practices had a mean of 4.1 ± 0.4 brpm, 

which was lower than the mean respiration rate value of 7.5 ± 

2.5 brpm reported from the MightySat oximeter shown in 

Supplemental Table 1. The average PR/RR ratios calculated by 

dividing average pulse rates reported with the Apple Watch by 

the count-based respiration rates had a mean of 13.2 ± 1.5, 

which was much higher than algorithm-based results of 7.9 ± 

2.4. In recent years, the bias of respiration rate extracted 

through algo- rithms has been corrected in other wearable 

devices. For example, a newer model of Garmin watch 

Vivoactive 4S reported average respiration rates centered 

around 4 brpm in Qi Gong meditation practices (based on 95 

practice recordings since November 2021), which matched 

count-based average respiration rates. 

 
3. Discussion 

 

Long ago, in the Yellow Emperor's Classic of 

Internal Medicine (Huang Di Nei Jing), the health 

advantages of practicing Qi Gong meditation were 

first outlined.1 While a large body of recent 

research on the therapeutic effects of meditation 

and Qi Gong has revealed  

 

 

beneficial impacts on well-being,2,3 One thing 

that makes it hard to evaluate this ancient 



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intervention is the fact that there are no objective 

ways to quantify the quality of Qi Gong 

practice.21 In this regard, the potential for 

changes in vital signs during Qi Gong meditation 

practice to serve as biomarkers in future clinical 

research of Qi Gong is encouraging. 

The MightySat fingertip pulse oximeter, Apple 

Watch, and Microsoft Band were used in this one-

subject five-year longitudinal study. 

Commercially available wearables include the 

Apple Watch and the Microsoft Band, while the 

MightySat is a medical gadget that gives clinical-

grade measurements of vital signs and has been 

authorised by the FDA.13 The MightySat stood 

out from the competition in 2016 when the author 

was looking for an oximeter due to its algorithm-

based respiration rate.22 With this function, all 

three vital signs—heart rate, respiration rate, and 

blood oxygen saturation—could be recorded 

simultaneously on the same device. While 

breathing rate remained constant, vital sign 

measures taken before, during, and after Qi Gong 

meditation sessions demonstrated physiological 

adaptability and resilience in the dynamically 

controlled SpO2, pulse rate, and perfusion index. 

While Qi Gong meditation exercise included a 

naturally longer exhale, a little drop in SpO2 level 

caused the heart rate to rise (Fig. 1). Under the Qi 

Gong meditation, the average SpO2 level declined 

by 0.4% and the average pulse rate rose by 2 bpm, 

despite the fact that the instantaneous SpO2 levels 

and pulse rates fluctuated dynamically.  

 

condition, shown in Figure 4. Also in 2017, 

Bernardi et al. showed that acute meditation 

practice reduced SpO2.23 Not only did long-term 

Qi Gong meditation training have this acute 

effect, but it also reduced resting SpO2, perfusion 

index, and pulse rate (Figs. 5 and 6). This is 

probably due to physiological adaptations brought 

about by years of LSBZQYXF meditation 

training. In a comprehensive study of endurance 

and yoga training, Reimers et al. also found that 

participants' resting heart rates decreased.24 The 

review paper did not assess the relationship 

between the decrease in resting heart rate and the 

change in blood oxygen saturation. Here, 

variations in SpO2 level were shown to 

correspond with the immediate dynamic control 

and adaptation of heart rate fluctuations.  

Moreover, the elevation of PR/RR ratios greater than 4 and 
5 is 

observed as a unique feature in the LSBZQYXF meditation 

state, which  has  not  been  reported  before.  The  4:1  or  

5:1  pulse- 
 

4. Long ago, in the Yellow Emperor's Classic of 

Internal Medicine (Huang Di Nei Jing), the 

respiration ratio was included as a measure 

for assessing health.25 In contrast to the 

resting before and after control 

circumstances, the distribution of 

instantaneous PR/RR ratio during Qi Gong 

meditation settings centred on values 

significantly larger than 4 or 5, according to 

the early preliminary data analysis in 2016. 

The author repeated tests using the 

MightySat oximeter in both resting and 

active states to have a better grasp of this 

phenomena. The MightySat oximeter had 

trouble recording the rate of breathing during 

riding until fatigue set in. The respiration rate 

signal remained unaffected by mild cycling, 

as seen in Figure 3. The distributions of the 

instantaneous PR/RR ratios centred around 4 

were preserved throughout both light cycling 

and sleep.  

In their December 2019 human investigation, 

Scholkmann et al. noted the same thing with 

the resting PR/RR ratio centred around 4.26 

In a review, the same authors synthesised this 

cardiorespiratory coupling phenomena and 

coined the term "Pulse-Respiration Quotient" 

(PRQ) to describe the PR/RR ratio of 4.27 

April 2019 marked the publication of this 

review. Although the statement in the Yellow 

Emperor's Classic of Internal Medicine 

(Huang Di Nei Jing) was made thousands of 

years ago, the authors state that the initial 

PRQ research was carried out in the 1920s. It 

was the Austrian scientist Rudolf Steiner 

who first highlighted the potential of the 



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PRQ 4:1 in understanding human 

physiology. In the years after Steiner's 

groundbreaking research, a number of 

German scientists have contributed to 

journals published in German since 1953. 

The work of Scholkmann et al. brought back 

German research into English literature. Age, 

gender, circadian rhythm, body posture, and 

exercise intensity were shown to have an 

effect on the PR/RR ratio. One participant in 

the present research sat quietly throughout 

the meditation condition, and data was taken 

at predetermined intervals. We have 

eliminated potential sources of data variance 

by avoiding the use of several individuals of 

various ages and genders, recording in 

different practice times, and subjecting them 

to diverse settings. This is the PR/RR ratio.  

 

while exercising was also recorded with the 

use of a Garmin watch.28 This finding 

demonstrated that three distinct forms of 

exercise—strength training, running, and 

elliptical training—exhibited average PR/RR 

ratios ranging from 3.5 to 4.7. The findings 

presented in this investigation were likewise 

in agreement with the observations made 

with the Garmin watch.  

According to Scholkmann et al.'s review, the 

PRQ may be defined in two ways: first, using 

measurements of PR and RR taken at the 

same moment; and second, using data taken 

at a longer interval, say 1 minute, to calculate 

the PR/RR ratio.27 The PR/RR ratio was 

calculated instantly in this research using 

data from the oximeter. Furthermore, this 

study revealed the first-ever simultaneous 

measurement of the blood SpO2 level and the 

instantaneous PR/RR ratio. In Figure 5B, we 

can see that there is a negative correlation 

between the instantaneous SpO2 level and 

the PR/RR ratio. This is due to the fact that, 

when the pulse rate is between 48 and 65 

bpm, there is also a negative correlation 

between the instantaneous SpO2 level and 

the instantaneous pulse rate (Fig. 5J). This 

five-year follow-up study found that 

assessing blood oxygen saturation level in 

conjunction with the PR/RR ratio may have 

an effect. In order to better understand the 

physiological processes by which Qi Gong 

meditation imparts its health benefits, may an 

enhanced PR/RR ratio serve as a quantifiable 

biomarker? When the cardiorespiratory 

coupling changes, how does it control the 

autonomic nervous system to make us more 

resilient? While these problems remain 

unanswered, Russo et al. (29), and 

Boyadzhieva et al. (30) addressed the 

physiological and neurological views on the 

benefits of slow breathing and its probable 

causes. Consistent with previous research, 

the present study found that LSBZQYXF 

meditation included breathing at a cadence of 

0.1 Hz, or 6 breaths per minute, while 

simultaneously promoting physiological and 

psychological calm.31 According to the 

research, this breathing rhythm improves the 

synchronisation of the heart and lungs.  

As a consequence of practicing LSBZQYXF 

Qi Gong meditation for an extended period 

of time, one may reduce their resting blood 

oxygen saturation (SpO2), heart rate (HR), 

and perfusion index (PI)—all of which 

contribute to better energy conservation. 

Some research suggests that physiological 

hypoxia might have positive effects on health 

by triggering adaptations in the body.32 By 

influencing lipid metabolism and redox 

homeostasis, intermittent hypoxia may have 

positive health effects.33 According to a 

mouse in vitro and in vivo investigation, 

cardiac regeneration may be facilitated by a 

moderate drop of heart rate (10%e20%) 

caused by anti-arrhythmic medications via 

stimulating the metabolic pattern switch.34 

Human pluripotent stem cell-induced 

cardiomyocytes (hPSC-CMs) cells also 

demonstrated heart regeneration caused by 

anti-arrhythmic drugs.34 In this research, 

participants who practiced Qi Gong 

meditation for 5 years had a decrease of 3 

beats per minute (5.4%). Could the impact 

shown in animal research and cell culture be 



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replicated in people by reducing the pulse 

rate, which promotes heart regeneration? In 

the current research on the benefits of 

meditation, the effects on the nervous 

system, in addition to the heart, have 

emerged as major themes.35 In this case, a 

decrease in resting SpO2 was associated with 

long-term Qi Gong meditation practice, 

according to a longitudinal observation. The 

advantages of this non-pharmaceutical 

treatment for controlling whole-body 

metabolism are brought to light by this 

discovery. These results require more 

investigation in order to confirm the 

significance of vital indicators during Qi 

Gong meditation.  

A handy tool for keeping tabs on your Qi 

Gong meditation sessions, the MightySat 

oximeter isn't without its drawbacks. To 

begin with, it does not capture heart rate 

variability (HRV) data often enough (one 

record per second). Secondly, while the 

device could show the plethysmographic 

waveforms, it couldn't export them for 

further analysis. This meant that the data 

collected couldn't be used for a thorough 

assessment of the cardio-respiratory coupling 

and vascular tension. Numerous studies have 

linked stress and ageing to HRV and cardio-

respiratory coupling.eleven, thirty-seven, We 

can delve deeply into the physiological 

mechanics of Qi Gong meditation using more 

frequent data points and the waveform.  

This longitudinal data is analysed 

retrospectively and compares an individual's 

moods before, during, and after meditation. 

Seasonal changes were minimised in the 

analysis by directly comparing the control 

and meditation conditions in each recording. 

Nevertheless, the present investigation is not 

without its caveats. First of all, this was not 

an attempt to recreate a laboratory 

environment; rather, it was an attempt to 

observe Qi Gong meditation in its own 

habitat. The duration of each exercise varied 

somewhat according to practical 

considerations. I think it's important to 

approach the findings with an inquisitive 

mindset. Secondly, the summary statistics of 

average values do not clearly reflect 

numerous dynamic elements of physiological 

regulations among the vital signs, which only 

happened in a limited duration during 

therapy. Additional quantitative measures of 

physiological resilience may be revealed in 

future analysis of time series with data 

captured more often. These results must be 

confirmed in a larger-scale randomised 

controlled trial that accounts for demographic 

variables such as age, gender, race/ethnicity, 

and medical history.  

 

5. Conclusions 

6. It was shown in this early retrospective 

analysis research that meditation may drop 

the blood SpO2 level, raise the pulse rate, 

and elevate the PR/RR ratio. The participants 

wore wearable devices that recorded critical 

vital signs throughout 5 years of Qi Gong 

meditation practice. A decrease in blood 

SpO2, pulse rate, and perfusion index was 

seen in the resting state after long-term 

LSBZQYXF training. Meditating causes a 

distinct physiological state distinct from 

sleeping, resting, and light cycling activity, 

characterised by an increase of the PR/RR 

ratio larger than 4 or 5. This paper details the 

results of a longitudinal study that tracked a 

healthy individual's vital signs as they 

progressed through LSBZQYXF meditation 

instruction and practice. These results have 

important implications for the development 

of future mechanistic studies of meditation 

intervention and for the evaluation of Qi 

Gong practice adherence. They suggest the 

possibility of objective metrics for evaluating 

the quality of meditation practice. 
 

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1.  


