ABSTRACT

CORRESPONDING AUTHOR:
Dr. Krishan Bihari Verma,
C/o, Dr. Ashok Kapoor,
20-21Q, Fruit Garden,
Railway Road,
NIT-05, Faridabad-121001.
Email: kbverma9@gmail.com

ABSTRACT: INTRODUCTION: Stress is a dangerous and significant problem of World, which affects physical, mental, behavioral, and emotional health. Yoga has been reported to control stress, to be beneficial in treating stress related disorders, improving autonomic functions, lower blood pressure, increase strength and flexibility of muscles, improve the sense of well-being, slow ageing process, control breathing, reducing signs of oxidative stress and improving spiritual growth. AIMS: The aim of present study was to investigate whether regular practice of Yoga for three months can reduce the cardiovascular hyper-reactivity induced by cold pressor test. MATERIALS AND METHODS: The study group comprised 62 healthy male subjects of 17-27 years age group. Initially there were 30 hyper reactors to cold pressor test. The hyper-reactivity of 23 volunteers converted to hypo-reactivity after the yoga therapy of three months (76.66%). Other parameters like basal blood pressure, rise in blood pressure, pulse rate and rate of respiration were also statistically significantly reduced (by using student ‘t’ test). STATISTICAL ANALYSIS: 2 tail student‘t’ test was done by using the standard formulas. RESULTS: Regular practice of yoga significantly reduces the cardiovascular hyper-reactivity in basal blood pressure, rise in blood pressure after one minute of cold stress, heart rate, and rate of respiration, after three month of yoga practice. CONCLUSION: Regular practice of yoga for three months reduced the cardiovascular hyper-reactivity to cold pressor test in subjects, who were hyper reactive to cold stress, possibly by inducing parasympathetic predominance and cortico-hypothalamomedullary inhibition.

KEYWORDS: Yoga, Bhastrika Pranayama, Cold pressor test, Healthy male population.

INTRODUCTION: Studies by many workers have demonstrated that the systolic blood pressure is variable and changes in it are seen in response to many forms of stimuli such as excitement, exercise,^5,25 pain,²¹ Yoga,^7,25 cold etc, but in comparison the yoga is more effective than the exercise.²⁵

Cold Pressor Test as a standard stimulus to study the vasomotor response was introduced in 1932 (Hines and Brown 1932). The subjects who showed greater response in his study were called HYPER-REACTORS. It was suggested by them that some of these hyper-reactors may possibly be candidates for hypertension in future.⁶ Yoga was found to have a considerable effect on different physical efficiencies of human being (Gopal et al 1973, Nayar et al 1975).

Lots of diseases occur due to stress in a modern society.^2,13 Hypertension is one of the commonest stress-induced cardiovascular disorder, posing a major public health challenge to population in socioeconomic and epidemiological transition.^{10, 27} Relief of stress and regular aerobic exercise are employed as general non drug therapeutic intervention in all patients with hypertension.^9,24,34 In the study of hypertension, cold pressor test, introduced by Hines and Brown^10,11 was employed to measure the cardiovascular reactivity.^14,18 The persons hyper-reactive to cold pressor test are susceptible for early onset of hypertension.^{12,14,15,17,20,36,39}

We tested whether regular practice of Bhastrika pranayama for 3 months can reduce the cardiovascular hyper-reactivity, as the pranayama had good benefits on cardiorespiratory system of human body.^{1,3,29,30,32,37}

material and method: The present study “Effect of Pranayama on Blood Pressure and Heart Rate in Hyper reactor to Cold Pressor Test” was carried out in the department of physiology Gold Field Medical College, Chhainsa (H.R.), after consent from the Institutional Ethical Committee.

30 young medical student aged 17-27 years who were hyperreactors to cold pressor test participated in the study. They were included in the study to perform “Bhastrika Pranayama” for the duration of the three month and each subject served as its own control. Each subject under went through a detailed history and clinical examination with the following criteria:

Inclusion Criteria:

1. Healthy, nonsmoker, with no cardio-respiratory disorders.
2. Subject not doing any type of physical exercise.

Exclusion Criteria:

1. Subject were taking other physical activity like Gym, athletics etc.
2. Subjects who are smokers, alcoholic, hypersensitivity, respiratory disorder, Diabetes Mellitus or any disease related with cardio-respiratory system.

Cold Pressor Test: For cold pressor test technique of Hines and Brown (1936) was followed exactly.^9,11

Technique of Test:

1. The subject ware allowed to take rest in supine position in a quite room maintaining the temperature 25-30°C for 20-30 minutes after that several reading of blood pressure were taken until a basal level was attained approximately.
2. With the subject still in supine position and with cuff of sphygomomanometer on right arm and the opposite hand (left) was immersed in ice water (3-5°C) to a point, just above the wrist joint with the hand still in water reading of blood pressure were taken at the end of 30 and 60 seconds. The highest of these two reading was noted as an index of the response.²⁷
3. The hand was removed from ice water after sixty second, reading had been taken and then the reading were taken every two minutes until the blood pressure returned to its previous basal level.
4. On the basis of the observation as changes in blood pressure the subject were divided into two groups- depending on their response to cold stress (Hines and Brown 1936).^{9, 11}

A- Hyper-Reactor: Those subjects in whom the systolic blood pressure rise more than 20 mmHg and or diastolic blood pressure more than 15 mmHg or cross the ceiling value of systolic blood pressure more than 145 mmHg and diastolic more then 95 mmHg.

B- Hyporeactors or Normoreactors: Those subjects in whom the systolic blood pressure rise did not exceed 20 mmHg and diastolic 15 mmHg.

Method for Practicing Bhastrika Pranayama:

1. The subject were asked to sit comfortably in any suitable meditation posture with the head, erect and both hands on their knee in a peaceful area, and well ventilated room with soft lightning and favorable temperature.
2. Breath in and out forcefully, without taking strain.
3. The abdomen should expand and contract rhythmically with the breath in pumping action.
4. After taking about 10 such respirations, take deep inspiration followed by breath holding for while, then exhale forcefully through both nostril.
5. It completes one round and take short rest in each round.
6. Start such breathing exercise with the slow rate and then gradually increase the rate over long practice.
7. Do not expand the chest or raise the shoulder and body should not jerk.

Measurement of Blood Pressure: A mercurial sphygmomanometer was used to record the blood pressure: The cuff was carefully applied on one inch above the cubital fossa and the right brachial artery was located out, the subject was allowed to take rest in supine position for 20-30 minutes in a quiet room.

After taking the rough systolic blood pressure by palpatory method, the both systolic and diastolic blood pressure was taken by auscultatory method. The appearance of sound [phase-1 of the Korotk off] recorded as systolic blood pressure and disappearance of this sound [phase-5 of Korotk off sound] was recorded as diastolic blood pressure.^18,22

Recording of Pulse: The pulse was recorded with the applying the tip of the fingers, in the radial groove over the radial artery and the subjects forearm being pronated and the wrist was slightly flexed.

The pulse rate was counted after sometimes so that any quickening produce due to nervousness of the subject, get subsided and the pulse resumed its normal rate.

The pulse rate was counted for complete one minute.¹⁸

DISCUSSION:

Reactivity to Cold Pressor Test: Studies by many authors have demonstrated that systemic blood pressure is variable and reacts to many forms of stimuli such as excitement, pain, cold, heat, and exercise.^{28, 33} Many normal young people may develop essential hypertension in future. With application of standard stimuli to such person and observing the response, it might be possible to differentiate a group in which an abnormally great reaction, resulted from such type of stimulus.

In the present study we used cold water (4⁰C) application to hand as a standard stimulus, introduced by Hines and Brown (1936).^9,11

In the present study basal systolic blood pressure in 62 subjects was observed varying between 100 to 140 mmHg with a mean value of 119.93 ± 7.5 mmHg. The corresponding figures for diastolic blood pressure were observed to be 66 to 90 mmHg with mean value of 77.29 ± 5.24.

On application of cold pressor stimuli for 60 second in entire series of 62 subjects on average rise of systolic blood pressure was 12.4±4.82 mmHg and for diastolic blood pressure it was 4.6±4.54 mmHg.

Hines and Brown (1936), has also observed a rise in response to cold application by 12.9±0.87 mmHg and 11.8±0.82 mmHg respectively in systolic and diastolic blood pressure.^9,11

According to criteria laid down by Hines (1936) the subject were divided in to two group i.e. hyporeactor [showing rise not more than 20 mmHg for systolic B.P. and/or 15 mmHg of diastolic blood pressure and hyperreactor [showing increase rise than above].^9,11

Hines and Brown later on modified the old criteria of hyperreactor and gave ‘new’ definition of hyperreactor and those having a rise of 15 mmHg diastolic or greater and a maximal basal diastolic pressure exceeding 90 mmHg.^{9, 11}

In the present study about 48% subjects found to be hyper reactors and 52% as hypo reactors, as per the criteria laid down by Hines and Brown.^9,11

Wirch, Jennifer L. Wolfe, Larry A et al (2006) divided hyper reactor in two groups designated as systolic and diastolic hyper reactors on the basis of increase in blood pressure, in systolic hyperreactors.³⁸

Systolic blood pressure rise more than 20 mmHg while diastolic B.P. may increase more than 15 mmHg or not. In diastolic hyper reactor systolic blood pressure rise not more than 20 mmHg while in rise in diastolic B.P. is always more than 15 mmHg.

In the present study systolic hyper reactor were found showing greater rise in systolic blood pressure. The mean rise was 24.72±4.4 mmHg and 12.63±5.55 mmHg in systolic and diastolic blood pressure respectively. Our value correlate with Hines and Brown (1936) observed a rise of 29.4±4.2 and 24.5±2.6 in systolic and diastolic blood pressure respectively.^9,11

In present study diastolic hyper reactor showing greater rise in diastolic blood pressure. The mean value of rise in blood pressure was 16.25±6.36 and 18±4.30 in systolic and diastolic blood pressure respectively. In the present study hypo reactors subjects showing mean rise in systolic and diastolic blood pressure was 13.6±3.6 and 10.66±2.5 mmHg respectively.

Our value correlate with- Hines and Browm (1936) observed on average systolic rise 11.4 mmHg and average diastolic rise 10.6 mmHg.^9,11

Heart Rate: In the present study heart rate was calculated by R.R. interval of E.C.G. initially, the heart rate of the subjects was found to be in the range of 60-100 per minute, average heart rate 82.06 with standard deviation 3.75 after 3 months of Pranayama, decrease in the average heart rate, was 78.23±2.38 per minute which is significant (p<.05).

These finding correlate with:

1. Bowman, A.J., R.H. Claton et al (1997) They found significant decrease in heart rate, the initial heart rate 69±8 per minute which decreased to 61±7 per minute with p-value <.05 which is statistically significant.⁴
2. Madan Mohan, U.C. Rai, V. Balavittal (1983) – They found significant decrease in heart rate, initially the heart rate was 82±8.66 per minute which decreased to 76±6.4 per minute with p value <.05 which is statistically significant.¹⁶

Pulse Rate: In the present study, the pulse rate of subjects initially were 81.23 per minute with S.D. 3.86 after 3 months of pranayama, the pulse rate changed to 78.16 per minute with S.D. 3.75 these finding were correlate with the following studies:

1. U.S. Ray, S. Mukhopadhyaya (2001), They found significant decrease in pulse rate initially it was 82.04±6.4 per minute, which decreased to 76.32±5.2 per minute with p value <.1 which is significant.²⁴
2. Trans M.D. Holly R.G. (2001) also found significant decrease in the pulse rate. The initial pulse rate was 80.26±3.1 per minute and it decrease to 77.52±4.6 per minute after practicing pranayama for 3 months.³³
3. Udupa K.N. et al (1975) not found significant decrease in pulse rate they found from 65.20±6.90 per minute to 65.40±2.90 per minute after practicing the pranayama for 6 months.³⁵

The decrease in heart rate and pulse rate was probably due to increased vagal tone together with decreased sympathetic discharges without shifting autonomic balance.^{5, 7, 19, 26} The decreased sympathetic discharge to the skeletal muscle vasculature may allow significant vasodilation to improve peripheral circulation.³¹

Blood Pressure: Initially, the mean systolic blood pressure of subject was 121.33 ± 10.3 mmHg which decreased after 3 months to 120.93 ± 9.01 mmHg with P value 0.022 which is significant. The diastolic blood pressure was 78.26±7.42 mmHg and after 3 months decreased to 78.2±7.40 mmHg with significant p value.022.

There finding correlate with Rashmi V., Dixit N., (2003) who also observed significant decreased in diastolic blood pressure.²³ Initially diastolic blood pressure was 74.80±4.32 mmHg which significantly decreased to 70.02±3.16 mmHg with significant p value (p<.04). Similar finding were also seen in following study.

Udupa K.N. (1975) found significant increase in systolic blood pressure and diastolic blood pressure after 3 months of pranayama they found initially mean systolic blood pressure 104.60±3.60 mmHg which increased to 106.00±7.30 mmHg and initial mean diastolic blood pressure was 87.80±1.80 mmHg, which increased to 89.00±1.00mmHg, with p <.001 which is significant.³⁵

Gopal K.S. (1973) found significant decrease in B.P. with initial mean value of S.B.P. 109 ± 6.36 mmHg which decreased to 108 ± 80 mmHg after practicing yoga.⁸ The D.B.P. was 79 ± 5.4 mmHg and after practicing pranayama, the D.B.P. decreased to 70.6 ± 6.49 mmHg with P < 0.001 which is significant.

RESULT: The present study was conducted on 62 male subjects of whom 30 were hyper reactor to cold pressor test (CPT).

These 30 hyper reactors were having mean heart rate of 82.06±3.75 and pulse rate of 81.23±3.86. This study shows that 3months pranayama significantly (p=0.048) decreases the heart rate to 78.23±33.96 and also significantly (p=0.016) decreases the pulse rate to 78.16±33.96 (Table: 5).

On the other hand 3 months pranayama shows a significant (p=0.22) decrease in both the basal systolic and diastolic blood pressure, respectively from 121.33±10.3mmHg and 78.26±7.42mmHg to 120.93±9.014mmHg and 78.2±7.40mmHg (Table: 6). On application of CPT the systolic and diastolic blood pressure shows an increased value, respectively as 142.44±6.6mmHg and 92.06±4.2mmHg, but the 3 months pranayama significantly (p<0.05) decreases the values to 136.86±6.4mmHg and 88.13±5.8mmHg.

STATISTICAL ANALYSIS: 2 tail student’t test was done by using the standard formulas. The p-value less than 0.05 were taken as statistically significant.

CONCLUSION: The pranayama techniques like – Bhastrika pranayama may cause shift of autonomic nervous control toward parasympathetic side which decreases the blood pressure and heart rate. So it may cause shifting of hyper reactivity to C.P.T. to normal reactivity. Thus, in the present study out of 30 hyper reactor subjects 23 become hypo reactor after 3 months of regular pranayama practice.

REFERENCES:

1.    Abraham B. Effects of 8-week nadi-shodhana pranayama training on Cardio-pulmonary parameters. Reviews of Literature- 2014, Jan; 1(6): Forthcoming.
2.    Bengt B. Arnetz and Ekman R. Weinheim. Stress in Health and Disease. Yale journal of biology and medicine. 2008, Mar; 81 (1): 53-54.
3.     Bhavanani A B, Mohan M., Sanjay Z. Immediate effect of chandra nadi pranayama (left unilateral forced nostril breathing) on cardiovascular parameters in hypertensive patients. International Journal of Yoga. 2012, Jul-Dec; 5(2): 108–111.
4.    Bowman A.J., Clayton R.H., Murray A., Reed J.W., Subham M.M. and Ford G.A. Effect of aerobic exercise training and yoga on the baroreflex in healthy elderly persons. European Journal at clinical investigation, 1997, May; 27(5): 443-449.
5.    Brian F. Robinson, Stephen E. Epstein, Beiser G.D. and Braunwald E. Control of Heart Rate by the Autonomic Nervous System Studies in Man on the Interrelation Between Baroreceptor Mechanisms and Exercise. Journal of Americal Heart Association. 1966; 19:400-411.
6.    Flaa A, Ivar K. Eide, Sverre E. Kjeldsen, Morten R. Sympathoadrenal stress reactivity is a predictor of future blood pressure: An 18-year follow-up study. Hypertension. Journal of the American Heart Association. 2008; 52:336-41.
7.    Ghiya S. and  Mattew CL. Influence of alternate nostril breathing on heart rate variability in non-practitioners of yogic breathing. International Journal of Yoga. Jan-Jun 2012; 5(1): 66–69.
8.    Gopal K.S., Bhatnagar O.P., Subramanium N., and Nishith S.D. Effect of yoga bana and pranayama on blood pressure, pulse rate, and some respiratory functions Ind. Jour. Phys. Pharma. 1973; 17: 273-276.
9.    Hines and Brown- The cold pressor test for measuring the reactibility of the blood pressure. Amer Heart. J.1936; 1: l1-13.
10.    Hines EA Jr., Brown GE. A Standard Stimulus for Measuring Vasomotor Reactions; Its Application in the Study of Hypertension. Proc Staff Meet Mayo Clin 1932; 7:332.
11.    Hines EA, Brown GE. Cold pressor test for measuring the reactibility of blood pressure. American Heart J 1936; 11: 1-9.
12.    Kasper. Hypertensive Vascular Disease; Harrison’s Principles of Internal Medicine. McGraw-Hill companies, Inc. 2005; 2 (16): 1463-1467.
13.    Kurl S., Laukkanen J.A., Rauramaa R., LakkaT.A., Sivenius J. and Salonen J.T. Systolic Blood Pressure Response to Exercise Stress Test and Risk of Stroke. Journal of the American Heart Association. 2001; 32:2036-2041
14.    Mahour J, Shrivastava SK, Rajak C, Asha Shrivastava. Effect of Specific Yoga asanas on Volunteers Having Cardiovascular Hyper-Reactivity to Cold Pressor Test. Journal of medical science and clinical research. 2014, April; 2(4): 665-672.
15.    Menkes MS, Matthews KA, Krantz DS, ULF Lundberg, Lucy A. mead et al. Cardiovascular reactivity to the cold pressor test as a predictor of hypertension. Hypertension 1989; 14: 524-530.
16.    Madan M, Rai V.C., Balavittal V., Thomcre D.P., and Gitanonda S. Cardiorespiratory changes during Savitri pranayama and Shavasana. The Yoga review, 1983; 3 (1): 25-34
17.    Nayar HS., Mathur RM. Kumar RS. -Effect of Yogic Exercises on Human Physical efficiency Ind. J. Med. Rds, 1975; 10:63-65.
18.    Pal G.K. and Pal P. Textbook of practical physiology. 1st edition. Sangam books ltd. 2001, July, 25; 227.
19.    Pal G.K., Velkumary S. and Mohan M. Effect of short-term practice of breathing exercises on autonomic functions in normal human volunteers. Indian Journal of Medical Research, 2004, August; 120:115-12.
20.    Park K. Social and Preventive Medicine. 20th Edition. Banarsidas Bhanot Publisher. 2009; 323.
21.    Paul J, Nafe, Kenneth S. Wagoner. The effect of pain upon systemic arterial blood pressure. The American Journal of Psychology. 1938, Apr.; 51(2): 390-397
22.    Perloff D, Grim C, Flack J, Frohlich ED, Hill M, et al. Human blood pressure determination by sphygmomanometry. Circulation 1993; 88: 2460-2470.
23.    Rashmi V., Dikshit N. Effect of meditation on respiratory system cardio vascular system and lipid profile. Ind Journ of physio. Pharmacology. October 2003; 46(4); 493-6.
24.    Ray US, Mukhopadhyoga S., Purkayastha S.S., Asnani V., Tomar O.S., Prasad R., Thakur L., Selvamurthy W. Effect of yogic exercise on physical and mental health of young fellowship course trainee's Ind. Jour. of Phys. and Pharmacology 2001; 45 (1): 37-53..
25.    Ross A., Thomas S. The Health Benefits of Yoga and Exercise: A Review of Comparison Studies. The journal of alternative and complementary medicine. 2010; 16 (1), 3–12.
26.    Rajesh K., Sharma K, Deepak K., Bijlani R.L. and Rao P.S. Short-term physical training alters cardiovascular autonomic response amplitude and latencies. Indian J Physiol Pharmacol 2004; 48 (2): 165–173.
27.    Ritesh M., Karia M. D., Mahavirsingh Rajput M. D., Hemant B., Mehta M. D., Pradnya A. and Gokhale M. D. Blood Pressure Response to Cold Pressure Test in Normal Young Healthy Subjects: A Prediction of Future Possibilities of Hypertension. Journal of physiology and pharmacology advances. 2012; 2(6): 223-226.
28.    Sahoo J K, Vatve M, Sahoo K D, Patil V V. Effect of specific “yogasanas” on cardiovascular autonomic function test. Pravara Med Rev 2010; 2(1): 10-15.
29.    Sharma VK, Trakroo M, Subramaniam V, Rajajeyakumar M, Bhavanani AB, Sahai A. Effect of fast and slow pranayama on perceived stress and cardiovascular parameters in young health-care students. International Journal of Yoga. 2013 Jul; 6 (2):104-10.
30.    Sinha AN, Desh D, Gusain VS. Assessment of the Effects of Pranayama/Alternate Nostril Breathing on the Parasympathetic Nervous System in Young Adults. Journal of Clinical Diagnostic Research. 2013, May; 7 (5): 821–823.
31.    Thomas G.D. Neural control of the circulation. Advances in Physiology Education. 2011, March 1; 35:28-32.
32.    Telles S., Yadav A., Kumar N., Sharma S., Visweswaraiah NK., Balkrishna A. Blood pressure and purdue pegboard scores in individuals with hypertension after alternate nostril breathing, breath awareness, and no intervention. Med Sci Monit. 2013, Jan 21; 19: 61–66.
33.    Trans M.D., Holly R.G. Lashbrook, Amstordan E.A. Effect of Latha yoga practice on the health related aspect of physical fitness. Prey cordial Autumn. 2001; 4(4): 165-170.
34.    Udupa K. N., Prasad R. C. Stress and Its Management by Yoga. 6th edition. Delhi: Motilal Banarsidass Publishers Pvt. Ltd; 2007, Jan. 1:131.
35.    Udupa K.N., Singh R.H. and Shehiwar R.H. Studies on the effect of some yogic breathing exercise (Pranayama) on normal person: Ind. Jour. of Med. res. 1975; 10 (2): 62-63.
36.    Verma V., Singh S.K. and Ghosh S. Identification of susceptibility to hypertension by the cold pressor test. Indian J Physiol Pharmacol. 2005; 49 (1): 119–120.
37.    Viveka P. J., Smita A., Singla R., Joshi A., Dhawan A., Kumar N.,  Deepak K. K., and Sreenivas V. Cardiac autonomic function in patients with diabetes improves with practice of comprehensive yogic breathing program. Indian J Endocrinol Metab. May-Jun 2013; 17(3): 480–485.
38.    Wirch J., Wolfe L., Larry A., Weissgerber, Tracey L. D., Gregory A.C. Cold presser test protocol to evaluate cardiac autonomic function. Applied physiology, nutrition and metabolism, 2006, June 1; 31(3): 235-243 (9).
39.    Wood DL, Sheps SG, Elveback LR, Schirger A. Cold Pressor test as a predictor of Hypertension. Hypertension. American Heart Association. 1984; 6: 301-306.

In present study, the age of subject was in the rage of 17-27 years. Most of the subjects belonged to age group 17-20 years followed by 21-24 years.

     Total subject = 62                      Mean age = 21.4

Out of 62 male subject, 30 subjects were hyper-reactor To CPT

Note: Out of 30 Hyper-reactors 06 subjects were found to have hyperreactivity to systolic as well as diastolic blood pressure.

Table 7: Table showing comparison of reactivity to Cold Pressor Test before and after three months of Pranayama (n=30)

After three months of pranayama out of 30 hyper reactors subjects 23 become hypo reactor while in other 7 subject reactivity did not change to C.P.T.

RECORDING OF BLOOD PRESSURE:

FIG. 1

FIG. 2

FIG. 3

FIG. 4