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Journal of Bodywork and Movement Therapies (2007) 11, 173–180

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Movement Therapies

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YOGA RESEARCH

Shavasana—Relaxation technique to combat stress

Geetanjali Sharma, MDa,�, K.K. Mahajan, MDa, Luv Sharma, MDb

aDepartment of Physiology, Pt. B.D. Sharma Post-Graduate Institute of Medical Sciences,Rohtak 124001 Haryana, IndiabDepartment of Forensic Medicine, Pt. B.D. Sharma Post-Graduate Institute of Medical Sciences,Rohtak 124001 Haryana, India

Received 27 August 2006; received in revised form 15 January 2007; accepted 17 January 2007

KEYWORDSShavasana;Yoga;Cold pressor test;Pressor;Stress

ee front matter & 2007bmt.2007.01.002

ng author. 24/9-J, Ma, India. Tel.: +01262 2ess: drgeeta1212@yaho

Summary The present study was undertaken on 60 young adults of both sexes todetermine if Shavasana could be an effective tool to combat stress. Stress wasexperimentally induced by cold pressor test (CPT) and effect was observed byrecording its effect on cardio-respiratory parameters viz. systolic blood pressure,diastolic blood pressure, pulse rate, respiratory rate and rate pressure product. Thestudy was divided into three setups. In the first setup, all parameters were recordedin basal state i.e. in supine position and after CPT. Second setup CPTwas done afterperforming Shavasana for 10min and for the third setup, effects of CPT wereobserved after subjects had undergone Shavasana training for 10min daily for 4weeks. All basal parameters progressively statistically significantly decreased afterperforming Shavasana for 10min and after its continuous practice for 4 weeks. Coldpressor induced stress showed statistically significant rise in all parameters in all thethree setups but this rise was blunted and a progressively lower percentage increasewas observed. It suggests that a person practicing Shavasana can successfully reducethe physiological effects of stress.& 2007 Elsevier Ltd. All rights reserved.

Introduction

Exposure to stress affects different functions of thebody through hypothalamus–pituitary–adrenal axisby activating the neurons releasing corticotropicreleasing hormones, antidiuretic hormones and

Elsevier Ltd. All rights reserv

edical Enclave, Rohtak13165/09416513989.o.com (G. Sharma).

catecholamines in the hypothalamus (Longstaff,2002).

It has been reported that following the practiceof yoga significant physiological and biochemicalchanges can take place (Joseph et al., 1981; Udupaet al., 1975; Chohan et al., 1984). Further, variedtypes of yogic practices not only help in prevention,but also can be helpful in treatment of specificdiseases such as hypertension, anxiety, asthma anddepression (Datey et al., 1969; Vijaylaxmi et al.,

ed.

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G. Sharma et al.174

2004; Sahasi et al., 1989). Kasiganesan et al. (2004)studied the effects of Hatha yoga and meditation ina group of 30 volunteers in age group of 25–35 yearson cardio-respiratory performance, psychologicalprofile and melatonin secretion; they found thatyogic practices resulted in improvement in cardio-respiratory performance and psychological profile.The systolic blood pressure, diastolic blood pres-sure, mean arterial pressure, and orthostatictolerance did not show any significant correlationwith plasma melatonin. However, the maximumnight time melatonin levels in yoga group showed asignificant correlation (r ¼ 0.71, Po0.05) withwell-being score. These observations suggestthat yogic practices can be used as psychophysio-logic stimuli to increase endogenous secretionof melatonin, which, in turn, might be responsiblefor improved sense of well-being (Kasiganesanet al., 2004).

The Sanskrit term ‘shava’ means dead body while‘asana’ means posture therefore Shavasana is thedead body posture, which of course is one ofcomplete repose and absolute relaxation. Thecorpse posture can both precede and follow asession of Hatha yoga postures. At the beginning ithas been shown to calm the body and focus themind in preparation for the postures to follow.Experience suggests that Shavasana relaxes theindividual profoundly (Coulter, 2001).

Vempati and Telles studied the effects of yoga-based guided relaxation compared with simply lyingdown and resting on sympathetic nervous systemactivity in 35 adult males. The subjects underwenttwo types of relaxation: (1) yoga-based guidedrelaxation and (2) rest lying down. Measures ofautonomic nervous system activity (including heartrate by ECG and skin conductance by galvanic skinresponse), oxygen consumption and volume of airbreathed were monitored. Assessments of auto-nomic indicators were completed for 15 subjectsand those for oxygen consumption and breathvolume for 25 subjects. Oxygen consumptiondecreased significantly and breath volume in-creased significantly after guided relaxation. Thetwo types of relaxation produced similar reductionsin heart rate and skin conductance. During guidedrelaxation, there was a reduction in the power ofthe low-frequency (LF) component of the heartrate variability spectrum and an increase in thepower of the high-frequency (HF) component,which suggested a reduction in sympathetic ner-vous system activity. Further analysis revealed thatsubjects who had a baseline ratio of LF/HF greaterthan 0.5 demonstrated a significant reduction inthe ratio after guided relaxation; whereas, subjectswith a baseline ratio less than or equal to 0.5 did

not show this change. Yoga-based guided relaxationdecreased sympathetic nervous system activitydepending on subject’s baseline levels (Vempatiand Telles, 2002).

Shavasana reduces all muscle tension, improvesvenous circulation, tones the whole nervous systemand relieves fatigue. In addition, the heart is restedand the distribution of blood is uniform. Thebreathing becomes slow, deep and rhythmic.Shavasana in conjunction with certain breathingtechniques has beneficially influenced hyperten-sion, heart ailments and other imbalances of thebody and mind (Swami Rama, 1998).

Earlier studies have suggested the effectivenessof Shavasana in producing psychosomatic relaxationin hypertensive and asthmatic patients. A study byVijaylaxmi et al. (2004) involved 13 patientssuffering from essential hypertension, who weregiven yoga training for an hour daily for a month.Blood pressure (BP) and heart rate were monitoredfor a month before and weekly during the training.There was a significant reduction (Po0.001) inresting heart rate and rate pressure product (RPP),after 2 weeks of the study. Further reductionsin systolic, diastolic (Po0.001) and mean BP(Po0.05) were noted at 3 weeks, and moresignificantly after completion of 4 weeks, for allparameters listed above (Po0.001) and pulsepressure (Po0.05).

Khanam et al. (1996) studied the effects of yogatraining on pulmonary and autonomic functions of 9diagnosed cases of bronchial asthma, twice a day,morning and evening, for an hour each for a total of14 sessions a week. The asanas in the training werepadmasana, tadasana, utkatasana, chakrasana tri-konasana and bhujangasana along with pranaya-mas. The autonomic function tests (parasympatheticactivity) studied before and after yoga traininginvolved a deep breathing test with the Valsalvamaneuver, while sympathetic function tests includedhand grip and cold pressor tests (CPTs), withstandard pulmonary function tests (FVC, FEV, PEFR,PIF, BHT and CE). The resting heart rate, after yogatraining (Po0.001) was significantly decreased (from89.55718.46/min to 76.22716.44/min). Sympa-thetic reactivity was reduced (Po0.001) evidencedby significant reduction in diastolic blood pressureafter the hand grip test. There was significant(Po0.001) decrease in peak inspiratory flow (PIF)rate, breath holding time (BHT) and chest expansion(CE) (Po 0.05). No significant change was seen inFVC, FEV, PEFR and parasympathetic reactivity.

Madan Mohan et al. (1983) studied the effect ofSavitri pranayam and Shavasana yoga on cardio-respiratory parameters (oxygen consumption, heartrate and diastolic blood pressure) in seven trained

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Shavasana 175

(for a year) and seven untrained volunteers, for atotal of 5 days. The trained subjects showedsignificant (Po0.001) reduction in heart rate,oxygen consumption and diastolic blood pressure(Po0.05). No significant change was noted in theuntrained subjects.

Selvamurthy et al. (1998) conducted a study toexplore the possible role of baroreflex mechanismin etiology of essential hypertension, and also tofind out whether by restoration of baroreflexsensitivity to a normal level, either by postural tiltstimulus, or by equivalent yogic postural exercises(yogasanas), whether essential hypertension, couldbe improved or controlled. Patients on therapeuticregimens were gradually withdrawn from drugtherapy and later divided into two groups of teneach. Group I (age 3471.7 years) was subjected toa 3-week course of 701 head up tilt for 30min daily,while Group II ((age 5073.3 years) undertookspecific yogic exercises (including Shavasana),equivalent to head up or head down tilt, for thesame duration. At the end of 3 weeks, there was asignificant decrease (Po0.001) in BP in bothgroups. Progressive changes in BP and heart rateresponses to tilt, during the 3 weeks course of tiltand yogic exercises, indicated gradual improve-ment in baroreflex sensitivity. Similarly, changes inother indices such as cold pressor response, alphaindex of EEG, level of blood catecholamines, andplasma rennin activity, indicated progressive at-tenuation of sympatho-adrenal and rennin–angio-tensin activity (Vijaylaxmi et al., 2004; Khanamet al., 1996; Selvamurthy et al., 1998; MadanMohan et al 1983).

Mogra and Singh (1986) studied the effect ofbiofeedback of BP and galvanic skin resistance(GSR), along with relaxation using the yogic postureof ‘Shavasana’, in 8 well motivated male hyperten-sives aged 25–45 years (six cases of essentialhypertension and two of renal hypertension).Subjects were asked to increase their GSR anddecrease their BP by passive volition. Each sessionlasted 30min. A total of 20 sessions was given toeach subject, spread over a period of 2 months.Mean systolic blood pressure and mean diastolicblood pressure were found to decrease from144.2mmHg (SD 10.5) to 119.7mmHg (SD 5.5) andfrom 95.5mmHg to 81.2mmHg, respectively.

Datey and Bhagat, 1977undertook a study on 113patients with hypertension to find out the effect ofrelaxation techniques, biofeedback training andShavasana. Patients were divided into 3 groups(I—taking/II—not taking medicines for hyperten-sion and III—with no response to medications). 27patients undertook biofeedback training and theremaining 86 underwent Shavasana training. The

total study period for all patients lasted a total of 9weeks involvng half hour sessions three times perweek. Subjective improvement of general symp-toms with a feeling of well-being was noted in mostof the patients. In the biofeedback group, therewas a significant reduction in the treated group ascompared to the control group. Twenty-one out of27 patients showed significant reduction in BP. Theaverage mean BP reduced from 118 to 103mmHg.At 4 months follow-up, the mean was 107mmHg. Inapproximately 50% of patients, the drug require-ment was reduced between 33% and 100% (average41%). In the Shavasana group, a fall of BP was notedin all groups. In group I, average mean BP camedown from 134 to 107mmHg. In group II, the fall inBP was from 102 to 100mmHg with drug require-ment reduced by 32%, while in group III the averageBP dropped from 120 to 110mmHg and drugrequirement was reduced to 29% of the originalintake (10 patients).

The present study aims at evaluating the efficacyof Shavasana to combat stress that has beenexperimentally induced by a CPT.

Materials and methods

The present study was carried out in the depart-ment of Physiology, Himalayan Institute of MedicalSciences, Swami Rama Nagar, Dehradun. 60 asymp-tomatic medical students of both genders (26 malesi.e. 43.3% and 34 females, 56.7%), between 18 and25 years, volunteered for this study. Subjectssuffering from the following disorders were ex-cluded from this study: cardiac diseases includingconduction defects detected by clinical examina-tion and ECG, congenital anomalies detected withthe help of X-rays and ultrasound and pulmonarydiseases. Ethical clearance from institutional ethicscommittee for this study, involving human volun-teers was obtained. All 60 subjects were furtherdivided into six subgroups, consisting of tensubjects each in order to facilitate individualprocedure monitoring and more precise parameterrecording for each subject. Each subject was askedto report to the laboratory 2 h after a lightbreakfast. He/she was given an explanation as tothe procedure, and informed consent was ob-tained. Physical parameters including age, weightand height were recorded. The experimentalprocedure was carried out in a quiet room at acomfortable temperature. No effort was made tosoundproof the room.

The study was divided into two phases A and Band three setups, wherein Phase A included twosetups—supine and Shavasana done for 10min,

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EXPERIMENTAL PROCEDURE

Phase A Phase B

Supine Shavasana training for one month

CPT CPT CPT

Shavasana for 10 minutes

Figure 1

G. Sharma et al.176

while Phase B included the third setup—Shavasanatraining for 1 month. Each subject took part in bothphases and all three setups (see Fig. 1):

�

In the first setup, the physiological (basal)parameters: BP, pulse rate (PR), respiratory rate(RR) and RPP were recorded in supine posture,which was followed by the CPT and subsequentrecording of parameters. � In the second setup, these parameters were

recorded when the subject practiced Shavasanafor 10min, and after the CPT.

�

Figure 2

In the third setup, the subject practiced Shava-sana daily for 10min for 4 weeks. Basal para-meters and the CPTwere repeated after 4 weeks.

Method of conducting cold pressor test(see Fig. 2)

CPTwas performed by immersing the subject’s lefthand, up to the first crease of wrist joint, in waterat 8 1C for 2min (Mishra and Mahajan, 1995) withthe subject in a supine posture. The temperature ofcold water was maintained constant, and the armwas kept in a comfortable position (with notension/stress) while the hand was in the water.BP, PR and RR were recorded on taking the hand outof the cold water after 2min (Fig. 2).

BP and PR were recorded by using electronicblood pressure meter (National). The instrumentwas frequently checked for accuracy with amercury sphygmomanometer.

RPP was calculated as a product of heart rate andsystolic blood pressure divided by 100 (Gobel et al1978).

Shavasana training technique (see Fig. 3)

For Shavasana training the technique recom-mended by Coulter (Coulter, 2001) was used. The

subject lay supine on a padded, but relativelyfirm, surface. The arms and thighs were comfor-tably abducted, the feet spread apart and handswere 12–18 in. (30–45 cm) away from the thighs,with forearms supinated. The subject was askedto relax and breathe abdominally. Shavasana waspracticed for 10min. Finally the subject wasready to come out of relaxation by bringing thearms overhead and turning on left side beforesitting up (Fig. 3) .

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Figure 3

Shavasana 177

Statistical analysis

The standard statistical procedure, paired t testwas used for comparison of effect of CPT onphysiological parameters in the supine state,performing Shavasana for 10min and after Shava-sana training for 4 weeks.

Description of statistical method used: The two-tailed P-value of a z-test: The z-test generates astandard score for x with respect to the data set(array) and returns the two-tailed probability forthe normal distribution. This function can be usedto assess the likelihood that a particular observa-tion is drawn from a particular population. ZTEST(array, x, sigma) Array is the array or range of dataagainst which to test x. X is the value to test. Sigmais the population (known) standard deviation.If omitted, the sample standard deviation is used.If array is empty, ZTEST returns to the #N/Aerror value.

Results

�

All cardio-respiratory parameter values werestatistically significantly reduced (Po0.001)after 10min of Shavasana practice, in compar-ison to the basal values in supine, and a further

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Table 1 Effect of Shavasana on cardio respiratory parameters (mean7standard deviation)

(n ¼ 60)

SBP (mmHg) DBP (mmHg) PR (/min) RR (/min) RPP

Supine 113.5736.51 73.374.91 74.874.47 1671.05 84.9578.06CPT (basal) 126.7375.57 82.6274.85 83.973.98 17.9271.26 105.7777.73Shav 110.6675.15 72.974.2 72.9373.04 15.0670.86 80.7275.47Post Shav CPT 114.7775.15 77.2374.2 7773.56 15.2370.96 87.8276.6Shav Tr 106.9875.73 70.2873.04 71.7473.02 13.8270.96 76.8875.65Post Shav Tr CPT 109.2775.47 73.1573.11 74.0373.15 13.8470.97 80.9275.97

Index: CPT—cold pressor test, Shav—Shavasana only once for 10min, Shav Tr—Shavasana training for 4 weeks, SBP—systolicblood pressure, DBP—diastolic blood pressure, PR—pulse rate, RR—respiratory rate, RPP—rate pressure product.

Table 2 P values of cardio-respiratory parameters in supine, Shavasana and after Shavasana training

Parameters (n ¼ 60) (P value)

SBP (mmHg) DBP (mmHg) PR (/min) RR (/min) RPP

Supine vs. Sh 4.50E�06 1.56E�01 3.10E�04 5.52E�11 4.00E�09Supine CPT vs. Sh CPT 1.00E�25 4,00E�06 7.00E�21 1.50E�24 4.39E�26Supine vs. Sh T 8.50E�11 2.54E�06 2.40E�08 2.70E�13 2.30E�13Supine CPT vs. Sh T CPT 4.40E�30 5.20E�21 3.70E�25 2.43E�30 5.11E�11Sh vs. Sh T 2.20E�13 8.54E�08 5.70E�10 6.30E�17 6.61E�15Sh CPT vs. Sh T CPT 2.83 E�40 1.13E�02 1.12E�10 1.00E�15 1.00E�40

Sh—Shavasana for 10min; Sh T—Shavasana training for 4 weeks. Statistical significance was assigned at Po0.001.Statisticalanalysis of parameters:

� All comparative values for basal parameters done in different settings (without CPT)—Supine vs. Shav, Supine vs.Shav Tr and Shav vs. Shav Tr—were highly statistically significant (Po0.001).� All comparative values for basal parameters done in different settings (after CPT)—Supine CPT vs. Post Shav CPT,Supine CPT vs. Post Shav Tr CPT and Post Shav CPT vs. Post Shav Tr CPT were also highly statistically significant(Po0.001).

G. Sharma et al.178

significant reduction was seen after Shavasanapractice for 4 weeks (see Table 1).

� Cold pressor stress produced a rise in all

parameters in the supine posture. The rise inall parameters was statistically significantlyreduced after Shavasana training for 4 weeks incomparison to Shavasana performed only oncefor 10min (see Table 2).

� Ten minutes of this classical yoga posture

reduced systolic and diastolic blood pressures,pulse and respiration rates more than supineresting. Supine cold pressor testing provoked arise in these parameters, but to a lesser extentin those with 4 weeks of Shavasana training.

Discussion

A limited number of scientific investigations,carried out in India and abroad, of certain formsof meditation (yogic or transcendental) have

indicated that these practices result in an equili-brium in the functioning of sympathetic andparasympathetic components of the autonomicsystem. A battery of tests can provide evidence asto autonomic balance e.g. heart rate, BP, RR, bodytemperature, skin resistance, metabolic rate,salivary secretion, gastro-intestinal mobility andsecretion. Any form of stress, physical or mental, ifcontinued for prolonged periods, results in sympa-thetic dominance as is evidenced by a gradual risein BP, heart rate, respiratory changes, increasedmetabolic activity, gastro-intestinal changes andendocrinal disturbances. Meditative practices gra-dually diminish sympathetic dominance, resultingin better balance between sympathetic and para-sympathetic components (Anand, 1991).

In order to study how the autonomic nervoussystem reacts to different forms of stress, variousexperimental assessments, involving methods suchas the Valsalva maneuver, head-up tilt, orthostaticstress and sustained handgrip, have been used.

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Shavasana 179

Change of posture from lying down to sitting orstanding up elicits effects on the muscle nervesympathetic activity, which is well documented(Burke et al., 1977). The autonomic response toimmersion of one hand in ice water has beendemonstrated to produce ischemia in subjects withcoronary artery disease as well as those withvasospastic angina. Although the CPT increasesheart rate and BP modestly in most subjects, afew will experience a major rise in BP, thusincreasing myocardial oxygen demand. This testhas been used in conjunction with simple ECGtesting and BP monitoring, and in the nuclearlaboratory has been used with blood angiographicmonitoring (Ellestad et al., 1996). The CPT wasused by Leblanc et al. (1960) on fishermen as earlyas 1960. Greene et al. (1965) studied the circula-tory dynamics during the CPT on patients withsystemic arterial hypertension, and a few normo-tensive subjects. Most subjects responded to CPTwith significantly increased BP, pulmonary arterialpressure and pulmonary vascular tension.

Several studies have been conducted to demon-strate the efficacy of Shavasana in terms of effectson cardio-respiratory parameters. Authors (Baggaand Gandhi, 1983; Gopal et al., 1973; Datey et al.,1969; Bera et al., 1998; Madan Mohan et al., 2002;Udupa et al., 1978) have reported significantdecreases in the above parameters after Shavasa-na, though the Shavasana training period under-taken by these subjects varied. Telles (Telles et al.,1993) demonstrated significant fall in O2 consump-tion, RR and tidal volume after Shavasana. In thepresent study, basal values of all parameters werestatistically significantly reduced on performingShavasana for 10min, and reduced still further(Po.001) after Shavasana training for 4 weeks.

A few studies have documented the effects ofexposure to cold stress. After 3 months of trainingof Shavasana, beneficial effect in borderline hy-pertensives (hyper reactors group) have beenreported i.e. statistically significant decrease inBP in response to CPT (Agarwal et al., 1977). MadanMohan et al. (2002) emphasized that even 1 weekof training of Shavasana can significantly modulatecold pressor response in normal subjects. In thepresent study exposure to the CPT after Shavasanapractice of 10min (only once) and Shavasanatraining for 4 weeks have demonstrated statisti-cally significant blunting of sympathetic responses.This effect increased in those practicing Shavasanafor 4 weeks.

In addition to awareness of the influence onBP and heart rate, study of RPP is gainingimportance as a mode of assessment of cardiacfunction as it indicates myocardial oxygen

consumption (Vijaylaxmi et al., 2004, Gobelet al., 1978). In the present study, mean RPP was84.9578.06 in supine posture, which after CPTincreased to 105.7777.73 (Table 1). After Shava-sana for 10min, and Shavasana for 4 weeks, thevalues were reduced to 80.7275.47 and76.8875.65, respectively; and on CPT the risewas only to 87.8276.6 and 80.9275.97, respec-tively. This significant reduction in RPP after thecold stress is suggestive of the decrease inmyocardial oxygen consumption and load on theheart, in agreement with others (Selvamurthyet al., 1998; Gobel et al., 1978). Similar observa-tions have been reported by Madan Mohan et al.(2002). The evidence suggests that inclusion ofShavasana may be of value in assessing sympatheticfunction.

This paper presents evidence that supports theuse of Shavasana training in relaxation therapy.Supine cold pressor testing provoked a rise in theseparameters but to a lesser extent in those with 4weeks of Shavasana training. It is suggested thatfuture researchers include variables such as heartrate variability and muscle sympathetic nerveactivity, to be able to comment more precisely onthe sympathetic drive or load on the heart.

Acknowledgment

The authors acknowledge with gratitude the helpand patience of the subjects who volunteered forthis study without whom this work would not havebeen possible.

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