A THE EFFECT OF YOGA AND MINDFULNESS MEDITATION ON ALPHA-AMYLASE LEVEL

Sport and Fitness Journal

Volume 10, No.2, May 2022: 85-96

E-ISSN: 2654-9182

THE EFFECT OF YOGA AND MINDFULNESS MEDITATION ON ALPHA-AMYLASE LEVEL

Brigitta^1*, Latisha Lubianca¹, Jessica¹, Tania Rosa¹, Eka Diah¹, Nila Wahyuni^2, I Putu Gede

Adiatmika²

¹ Magister Program of Biomedical Science Anti Aging Medicine Medical Faculty Universitas Udayana, 80234,

Denpasar, Indonesia

²Physiology Department Medical Faculty Universitas Udayana, 80234, Denpasar, Indonesia Email : [email protected]

ABSTRACT

In recent years, a lot of behavioral studies have shown that physical exercise and yoga have a positive impact on one’s physical and mental health. Yoga, which is increasingly used in the clinical setting of various mental and physical health problems, especially stress-related illnesses and concerns, has shown promising effects. The purpose of this study was to investigate the effects of mindful meditation and yoga in reducing salivary alpha-amylase levels, as a stress biomarker. This research is focused on evaluation of the stress levels in one’s body by measuring the levels of salivary stress marker alpha-amylase in accordance with yoga and mindful meditation. This study will focus on literature review using Boolean operator with databases from ScienceDirect, Pubmed, and Cochrane.

Keywords : alpha-amylase; yoga; meditation; mindfulness; stress ; biomarker; exercise

INTRODUCTION

Stress is a ubiquitous phenomenon that is found in the daily lives of humans and animals. The longer stress persists, the more likely it is to have harmful effects, eventually leading to negative health consequences, including but not limited to cardiovascular, immune, nervous, and endocrine systems¹. In this respect, stress has been shown to cause, exacerbate and prolong psychological and physical illnesses².

Mindfulness meditation and yoga have been long considered as alternatives to traditional mental health support. These are very popular tools for reducing stress and improving productivity and overall mental health^3,4. Mindfulness meditation is one of two traditionally identified forms of meditation. Mindfulness meditation, which is also known as "insight meditation" or "Vipassana meditation," plays an increasingly important role in defining how meditation can contribute to therapeutic growth and self-development. While all meditations develop the ability to focus and focus, mindfulness meditation is primarily non-judgmental to the subject of attention rather than a single subject-focused consciousness such as words or mantras³.

Different forms of yoga have different goals and focal points. Meditation Yoga (Hatha Style) focuses on careful breathing techniques, flexibility, and meditation⁵, while Power Yoga (Vinyasa Style) focuses on maintaining strong poses and muscular endurance⁶. It has been shown to achieve metabolic intensity similar to that of a moderately intense exercise. Both meditation yoga and power yoga have been reported to reduce stress levels over time⁷.

Alpha amylase is a non-invasive biomarker that can be used to study stress in the body. It is the most abundant enzyme in human saliva and is responsible for breaking down carbohydrates and starch. Alpha amylase has been shown to be secreted in response to sympathetic nervous system stimuli and increased in response to psychological stressors, which may be a useful parameter for measuring stress¹.

This article aims to investigate the effectiveness of yoga and mindfulness meditation interventions to reduce the individual stress biomarker alpha amylase, thus building the lead up to further studies to find how much it really prevents and reduces stress. The purpose of this article is to

look at and examine whether mindful meditation can be an alternative and complementary approach for managing stress.

METHODS

• a.    Methodology

Literature search related to the effect of Yoga and meditation on alpha amylase was performed on March 16th until 17th, 2022. Three databases are searched using Boolean operator (Science Direct, Pubmed, and Cochrane). Inclusion criteria includes trial in human, meta-analysis, systemic review, randomized controlled trial, observational study and articles within 10 years. Exclusion criteria on journal that is more than 10 years, animal subject and Non – English paper.

Table 1. Search Strategy

Database	Search Strategy	Hits	Selected
Pubmed®		1782	18
Science Direct®	(Yoga OR Meditation OR * OR Stress*) AND Alpha Amylase	28950	29
Cochrane®		455	10

• b.    Material and procedure

Based on the database search, 31178 papers have been obtained. Inclusion and exclusion criteria were then applied. The paper will be filtered for doubles and full-text availability. The process is illustrated in the figure below.

(Yoga OR. Meditation OR Stress) AND (Alpha Aniylase/

Inclusion Criteria:

• -    Trial in Human

• -    Meta-Analysis

• -    Systematic Review

• -    Randomized Controlled Trial

• -    Obsenational Study

• -    IOYearsold

Exclusion Criteria:

• -    Animal Subject

• -    Non-English Paper

• -    More than 10 Years old

Figure 1. Search Strategy

A total of 31178 journals were found. The application of inclusion and exclusion criteria narrowed the article to 57. Final articles obtained for review were 32.

Sport and Fitness Journal

E-ISSN: 2654-9182                                         Volume 10, No.2, May 2022: 85-96

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RESULTS

The data extraction of the eight journals is presented in Table 1.

Table 1. Data Extraction of Literature Review Results

No Author, Year of Research	Participant/      Outcomes        Intervention and        Duration     Frequency        Research         Research Result Research                        Research Purpose      (weeks or                      Methods Groups                                                months)
1.   Garcia- Sesnich et      al., 2017 8	26   volunteers  sAA and sCort   Kundalini yoga (KY)  3 months    Twice a week 90  Randomized     The study showed KY practice had from the North                    practice                                minutes  of KY  control trial       an immediate effect on salivary campus      of                                                               practice  for  3                      cortisol. The activity of alpha‐ University   of                   Research purpose: to                months                             amylase did not show significant Chile                             determine   the   KY                                                    changes. effect, immediate and after 3  months  of regular practice, on the perception          of psychological    stress and the salivary levels of cortisol and alpha‐ amylase activity.
2.   Anguilar et al., 2021 9	74      medical sAA and sCort   Mindfulness-based     3 months     A      one-day Randomized     The study showed MBI can reduce students    (third                    interventions (MBI)                     theoretical         controlled trial    psychobiological stress markers, semester), at the                                                           introductionfour                      assessed via repeated measures of end of the term,                   Research     purpose:                 three-hour                           sAA and sCort in daily life. were about to                   examines the effects of                 evening sessions take their first                  MBI on stress, sAA                every two weeks major exam                         and sCort in daily life.                  and a final two- hour-session   at

the end of the intervention period.

3.	Fakharir	20 post CABG	sAA and sCort	Yoga-cardiac	8 weeks	60 minute per	Randomized	The results showed that combined
	ad et al., 2020 21	patients       in Shahid RajaieHeart Center       in Tehran		rehabilitation Research purpose: to investigate the effects of rehabilitation and yoga practice on salivary levels of alpha-amylase and cortisol in patients after CABG.		sessions, 3 sessions per week for 8 weeks	controlled trial	yoga and rehabilitation training had a significant effect on salivary cortisol but these interventions did not show a significant effect on salivary alpha-amylase.
4.	Siederve s et al., 2014 22	28 students from science and math charter school in Charleston	BP, sAA and sCort	Hatha yoga (HY) practice Research purpose: to determine the effects of Hatha Yoga on salivary alpha-amylase among normotensive and prehypertensive youth.	3 months	90 minute sessions on alternating days (cycles of two sessions 1 week followed by three sessions the next week) throughout 12-week period	Randomized controlled trial	The results showed no statistically significant group differences were observed with changes of salivary cortisol or alpha-amylase levels but the HY practice demonstrated potential to decrease resting BP, particularly among prehypertensive youth.
5.	Kukihara et al., 2022 28	44 care workers who worked for elderly care facilities in rural Fukuoka.	sAA	Mindful meditation and yoga Research purpose: to investigate the effects of mindful meditation and yoga on reducing burnout and stress in care workers who assist elderly individuals	6 weeks	60-minute each week for six weeks	Randomized controlled trial	The results indicate that practicing mindful meditation or yoga for 60 minutes once a week for six weeks can reduce care workers’ burnout, as well as reducing bomarker of stress (sAA ), but both are not significantly different.

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6.	Haslam	77 mindfulness-	sAA	Mindfulness	Cross	Questionnaire	Randomized	Greater depth of meditation appears
	et      al., 2017 29	based      stress reduction (MBSR) instructors		Meditation Research     purpose: characterize sympathetic activity by using waking salivary alpha-amylase  (sAA) concentrations and and to    examine    the association   between meditation     (depth, dose and duration) and the   waking   alpha amylase response	Sectional	(the number of years participans spent meditating, the average number of days per week and the amount of minutes per day)	controlled trial	to be associated with a healthier sAA awakening slope, years of meditation was not associated with the awakening sAA slope.
7.	Mehrsafa r et al., 2019 31	26  male  elite Wushu athletes	sAA and sCort	MBI Research     purpose: examines the effects of MBI on competitive anxiety,            self confidence, mindfulness,      and autonomic        and biomarkers      stress responses     to     a competition in elite athletes	8 weeks	Weekly one-hour workshop sessions, daily 30 minutes   home meditation practice,     and weekly   group- based  mindful- Wushu sessions	Randomized controlled trial	The mindfulness group lower sCort daily levels (p = 0.001) but unaffected in daily sAA (p = 0.742) 8-week MBI was associated with decreased competitive anxiety, stress-related biomarkers, and enhanced self-confidence and competitive mindfulness in elite Wushu athletes, but could not rely on one stress biomarker only.
8.	Ducheni m et al., 2015 32	32 workers from a surgical intensive care unit (SICU) that work in high-	sAA	MBI Research purpose: to determine if a workplace stress-	8 weeks	Once per week with 60 minute every sessions except for week 5 that lasts 2	Randomized controlled trial	Levels of sAA were significantly decreased in the intervention group but with no changes in the control group. There was a positive correlation between sAA levels and

	Sport and Fitness Journal
E-ISSN: 2654-9182	Volume 10, No.2, May 2022: 85-96
stress settings	reduction intervention                 hours        and burnout scores. decreases reactivity to                 includes mindful stress among personnel                 eating exposed to a highly stressful occupational environment

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DISCUSSION

• a.    Association between Stress dan Alpha-amylase (α-amylase)

Stress is the word we use to describe an organism's automatic process or mechanism in reaction to real or perceived demands from the environment. Stressors can be biological, environmental, social, emotional, or psychological, to restore balance⁵. Dysregulation of the neurobiological stress system can occur if there is permanent exposure to a stressor but there is a failure to recover from that stressor^6,10. In stressful situations, the body's physiological and psychological reactions are given warning signs to help our bodies adapt to the current situation. At the physiological level, there is activation and harmonization between the central and peripheral nervous systems¹¹. Activation of the hypothalamus and brainstem on the central nervous system when there is an outflow from the hypothalamic-pituitary-adrenal (HPA) axis and the autonomic nervous system (ANS) including the medullary sympathetic adrenal (SAM) and the parasympathetic system are part of the peripheral nervous system¹².

As a stress biomarker, cortisol has been extensively studied, but it is clear that the ANS is also important in biological stress processes and also in stress-related diseases². Stress studies suggest that salivary alpha-amylase (sAA) has emerged as a viable and reliable marker of ANS activity. Alphaamylase (α-amylase) is a non-invasive biomarker to stress in our body^1,13. An easy, fast and non-invasive measurement that can be done by collecting participants' saliva, this method is often used in the acute stress literature, especially because it makes research easier because samples can be easily collected from home^2,14. The enzyme in human saliva and has been shown to be secreted in response to sympathetic nervous system stimuli and increased in response to psychological stressors, which may be a useful parameter for measuring stress¹. The character of salivary alpha-amylase is that there is a decrease in sAA levels in the first 30 minutes after waking up and then persists even progressively increases throughout the rest of the day, there is a difference with cortisol levels which immediately reach peak values within half an hour after waking up^2,15.

• b.    Association between Yoga and Alpha Amylase

Yoga is an ancient type of stress management that aims to bring the mind, body, and spirit together^7,8. It has grown increasingly popular in many countries in recent years^7,18. There are many forms of yoga and each form has its own theoretical underpinnings and methodologies, even though there are similar aspects such as regulated breathing, meditation practices, and physical postures^8,9.Yoga has been demonstrated in studies to reduce mental stress and negative moods, as well as to alleviate psychological symptoms by reducing anxiety and anger level⁷. Long-term yoga training also lowers stress-related psychological symptoms including anxiety and rage^8,10.

A case control study was conducted by Garcia-Sesnich et al in 2017 to seek the immediate and after 3 month effect of Kundalini Yoga (KY) on the sense of psychological stress, as well as salivary cortisol and alpha-amylase activity on 26 individuals (age ranging from 18 to 45 years-old). KY focused on the practice of kriya and meditation, as well as mantra chanting. Participants were divided into two groups namely, 1) study group consisting of beginners in KY practices and 2) not doing KY at all. Participants will be observed for 3 months. To assess immediate and longitudinal effects, four samples were taken from the yoga group in the beginning, middle, and end of the first and last classes. Two samples were taken from the control group at the start of the trial and after three months. The study group alpha-amylase activity was 34.03±21.68 U/mL at the start of the study and 38.01±20.14 U/mL after three months of yoga classes, whereas the control group values were 43.82±18.24 U/mL compared to 41.02±19.95 U/mL. Comparison between group values showed no significant changes (P=0.25 and P=0.72) even after three months in the study group (P=0.37) nor control group (P=0.67). The activities before and after the first and last classes were used to determine the immediate effect. The alpha-amylase value from before the first class were 34.03±21.68 U/mL and after 40.73±20.44 U/mL, whereas before the last class 38.01±20.14 U/mL and after 37.68±23.71U/mL. We found no immediate effect of yoga practice on salivary alpha-amylase activity before or after the first and last classes (P=0.26 and P=0.85). The results showed there are no major changes either in longitudinal or immediate effect of alpha-amylase activity between the KY group

and the control group. However, this study has several limitations, one of which, the small number of population it was conducted⁸.

A recent randomized controlled clinical trial in 20 post coronary artery bypass grafting (CABG) patients revealed combining yoga and rehabilitation had a positive impact on salivary levels of the stress markers investigated. As a result, this sort of workout is suggested for secondary prevention of cardiovascular disease (CVD). In this study all of the participants ranging in age from 45 to 75 years-old were randomly assigned to one of two groups: 1) yoga-rehabilitation group and 2) rehabilitation group. Participants in the trial after a minimum of 12 hours of nocturnal fasting, saliva samples were obtained and will be monitored for 8 weeks and. According to the findings, the combined intervention of rehabilitation and yoga had a noticeable effect on salivary cortisol levels (P = 0.028). However, there was no major impact of these therapies on the sAA levels (P = 0.193). In this study, long-term rehabilitation and yoga training did not have a significant effect on alphaamylase changes in coronary artery disease patients after surgery. Alpha-amylase has been shown to have a circadian rhythm, and the interaction of time of day (morning and evening) and exercise activity had an effect on sAA levels; this variable might have been influenced by distinct surface reactions in this study²¹.

On the other hand, a pilot trial study by Siederves et al in 2014 to see the effects of Hatha Yoga on salivary alpha-amylase among normotensive and prehypertensive youth²². This type of yoga is a combination of physical postures with breathing and/or meditation activities⁵. There are 28 individuals participating in this trial with a mean age of 12.3 ±0.4 and divided into, 1) Hatha yoga program (HYP) and 2) attention control (AC) that will be assigned to a music or art program. Participants will be observed for 12 week and the saliva samples were collected at night, at awakening and at 30 and 60 minutes after waking up. The results showed salivary alpha amylase levels of the HYP group dropped significantly from pre- to post-intervention (Cohen d = 0.34; prehypertensive d = 0.20) but the prehypertensive AC group alpha amylase level rose (prehypertensive Cohen d = 0.30). The findings in this study suggest reductions of alpha amylase levels leading to reduced sympathetic nervous system (SNS) activation may have partially contributed to reductions in blood pressure (BP). Salivary alpha-amylase is a biomarker of SNS activation, a reduction in the markers infers a shift in SNS regulation toward parasympathetic dominance that relates to decreased BP²².

• c.    Association between mindfulness meditation and Alpha Amylase

Meditation is a practice in contemplation or reflection which promotes general mental wellbeing and development²³, such as expanding tranquility, physical relaxation, improving psychological balance, accomplish an intellectually clear and stable state^3,24. Mindfulness is defined as selfobservation that trains focus on the present moment while accepting and acknowledging all physical thoughts, emotions, and feelings²⁵. Mindfulness leads to decrease the negative impact associated with the fact that stress factors are not automatically assessed as threatening⁹. Meditation is closely related to the concept of mindfulness, therefore it is regularly alluded to as “mindfulness meditation”²³. Mindfulness meditation has been shown to reduce psychological stress in many populations, including _eldery26,27,28_.

The collective previous studies suggest a beneficial effect of mindfulness meditation on stress^29,30. Recent longitudinal study with 74 medical students at the end of third semester showed the Mindfulness-Based intervention group can reduce psychobiological stress markers, including sAA and saliva cortisol compared to the control group. The students in the mindfulness group showed statistically significant results in lowering sAA levels (b = -0.361, p = .043, M = -6244.69, SD = 44,386.82)⁹.

Similar previous research conducted by Haslam et al in 2016, with 77 mindfulness-based stress reduction (MBSR) instructors examined the relationship between meditation (dose, depth and duration) and the alpha-amylase. sAA samples were taken four times (right away upon waking, 15 minutes, 30 minutes, and 45 minutes intervals after waking. In this study, the population with deeper meditation was related with steeper decline in awakening sAA (p = 0.02) compared to the population who meditated less profoundly. Whereas years of meditation (p = 0.15) and dose (p = 0.24) were not related to reduced awakening sAA²⁹.

But on the other hand, a pilot study conducted by Mehrsafar et al in 2019 on 26 elite Wushu athletes during a competitive event. Competition has been associated with increased sAA and serum

cortisol (sCort). The experimental group participated in a 8 week mindfulness program that included weekly one-hour workshop sessions, in-house meditation practice, and weekly group-based mindful-Wushu sessions. The mindfulness group lower sCort daily levels (p = 0.001) but unaffected in daily sAA (p = 0.742) This study indicated that mindfulness intervention may be associated with attenuation of physical and psychological responses to stress during competition, but could not rely on one stress biomarker only³¹.

• d.    Effect of yoga and meditation to Alpha Amylase

Both yoga and mindfulness mediation interventions can reduce stress biomarker alpha amylase, but both are not significantly different²⁸. The combination of yoga and mindfulness meditation showed significant changes in sAA levels³².

A randomized control trial conducted by Kukihara et al in 2021 on 44 eldery care workers who were randomly divided into three intervention groups: control vs yoga, control vs mindfulness, and yoga vs mindfulness. Yoga group practiced hatha yoga, mindfulness group trained in mindful meditation, both yoga and meditation sessions took approximately an hour, once a week for six weeks. Level of alpha amylase was measured using NIPRO: T-110-N. The result showed no significant difference between alpha amylase in the yoga group (M=36.86, SD=23.44) and the mindfulness group (M=35.53, SD=22.68, P= ns). On the other hand, there were significant differences between the yoga group (M=11.57, SD=3.06) and the control (M=75.75, SD=38.78, P=0.004), and between the mindfulness group (M=35.53, SD=22.68) and the control (M=75.75, SD=38.78, P=0.002). This research concluded that practicing yoga or mindful meditation for an hour once a week for six weeks can reduce biomarkers of stress²⁸.

A randomized pilot study conducted by Duchemin et al in 2015 investigated a work related stress intervention that reduces stress reactivity in 32 workers from a surgical intensive care unit (SICU) that work in high-stress settings. Participants were divided randomly into two groups namely, 1) study group participated in 8 week mindfulness based intervention (MBI) consisting of mindfulness meditation, gentle yoga and relaxation music 2) control group. The saliva samples were taken in the workplace during work day between 1 till 3 PM to represent the impact of work-related stress on the salivary alpha-amylase level. At the beginning of the study, results showed there was no difference between the two groups (p = 0.6812, t = 0.4152) and the average salivary alpha amylase levels for all participants were 93.6±15.9 units/ml (mean±SEM). The MBI group sAA levels from the beginning until after 2-month were lowered by 40% (p = 0.026, t = 2.562) compared with 4% of the control group. According to the findings, MBI can reduce stress reactivity among SICU personnel³².

The results indicate that practicing mindful meditation or yoga, or both can reduce the biomarker of stress^28,32. It is strongly recommended and encouraged people, especially those who work in a stressful environment to practice mindful meditation or yoga¹². As health professionals, we should advise people to practice yoga and mindfulness as holistic therapy for stress in order to enhance their quality of life. Perhaps most importantly, yoga and mindfulness is available to anyone at any time or place, making it a cost-effective, flexible, and psychologically beneficial holistic practice from occupational stress and burnout²³.

CONCLUSION

There is a positive correlation between yoga and meditation on the level of alpha amylase. Kundalini and Hatha style Yoga have shown greater outcome compared to other types of Yoga. Deeper meditation was related with steeper decline in awakening sAA, whereas years of meditation and dose were not related to reduced awakening sAA. The fall in alpha amylase in turn reduces stress and improves overall productivity and mental health status. Practicing yoga and mindfullnes are beneficial in reducing occupational stress and burnout thus improve quality of life.

CONFLICT OF INTEREST

The authors declare no conflict of interest.

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