Int J Biol Med Res. 2012; 3(2): 1662-1666 Int J Biol Med Res Volume 3, Issue 1, Jan 2012 www.biomedsidiret.om BioMedSiDiret Publiations Contents lists available at BioMedSiDiret Publiations International Journal of Biologial & Medial Researh Journal homepage: www.biomedsidiret.om International Journal of BIOLOGICAL AND MEDICAL RESEARCH Original Artile A study on modulation on ardiovasular response to yoga training * a Qairunnisa. S, M. Chandrashekar,M. Revathi, Ambareesha Kondam, B.A. Madhuri & M. Suresh Tutor in Department of Physiology, Meenakshi Medial ollege & Researh institute, Kanhipuram, MAHER University Professor in Department of Physiology, Meenakshi Medial ollege & Researh institute, Kanhipuram, MAHER University Assitant professor,in department physiology, Meenakshi Medial ollege & Researh institute, Kanhipuram, MAHER Univeersity. A R T I C L E I N F O A B S T R A C T Keywords: Pranayama Deep breathing test Postural Tahyardia index Valsalva ratio Pratie of breathing exerises like Pranayama is known to improve autonomi funtion by hanging sympatheti or parasympatheti ativity. Speifi breathing exerises had ontinuous good improvement in respiratory endurane in patients suffering Bronhial Asthma. This study was designed to quantity and ompare the instantaneous heart rate dynamis and ardiopulmonary interations during sequential performane of one Yogi meditation breathing patterns with different protool, Beat to beat heart rate variane and ontinuous breathing signals from 20 experiened subjets (10 Males; 10 Females;) was assessed. The experiened groups were subjets pratiing pranayama for duration to a 2-3years.The autonomi funtions of the ardiovasular system of the subjets were assessed in detail. P Value< 0.05 was onsidered to be statistially signifiant, Our results showed no signifiant hange in resting heart rate ( P > 0.05 ) but there was signifiant inrease in deep breathing ( P < 0.05 ), postural tahyardia index ( P < 0.01 ) and valsalva's ratio ( P < 0.01 ). These findings suggest that different meditative breathing protools may evoke ommon heart rate effets, as well as speifi responses. The results support the onept of a Meditation paradox, sine a variety of relaxation and meditative tehniques may produe ative rather than quiesent ardia dynamis, assoiated with prominent low frequeny, heart rate osillation or inreases in mean resting heart rate. These findings also undersore the need to ritially assess traditional frequeny domain heat rate variability parameters in making inferenes about autonomis alterations during meditation with slow breathing. Copyright 2010 BioMedSiDiret Publiations IJBMR - ISSN: 0976:6685. All rights reserved. 1. Introdution Yogi tehniques like regular pratie of breathing exerises (pranayama) are known to improve physial and mental health as they inrease parasympatheti tone, derease sympatheti ativity, improve ardiovasular and respiratory funtions and derease the effet of stress and strain on the body [1-3]. Bhattaharya & Krishna swami have given several reports on the benefiial effets of yoga training on physiologial funtions [4]. Pranayama breathing exerises improve autonomi & pulmonary funtions in asthma patients [5]. In the yogi system of breathing, the right nostril dominane orresponds to ativation of * Corresponding Author : Qairunnisa. S Tutor in Department of Physiology, Meenakshi Medial ollege & Researh institute, Kanhipuram, MAHER University E.mail: ambreesh.kondam@gmail.om Copyright 2010 BioMedSiDiret Publiations. All rights reserved. 'pingala' the subtle energy hannel of yoga is related to sympatheti arousal and left nostril dominane and Ida' svara with parasympatheti ativation [6]. A signifiant improvement in ardiovasular endurane & anaerobi power ours as a result of yoga training [7]. Anient yogi texts have desribed a rapid breathing leansing pratie (Kapalabhati) as stimulating, & slow regulated breathing, partiularly through alternate nostrils (Nadisuddhi pranayama) as alming [8]. Kapalabhati was found to ause autonomi ativation. This was observed as an immediate effet during three ontiguous sessions of 5 minute eah, in terms of an inreased heart rate and systoli blood pressure during kapalabhathi [9]. In Nadisuddhi pranayama pratied for 4 weeks, there were dereased heart rate, as well as systoli & diastoli blood pressure levels [1]
1663 In Surya anuloma viloma pranayama and Kapalabhati type of breathing exerise there is inrease in sympatheti tone or derease in vagal tone [10]. Pratie of short Kumbhak pranayama breathing at slow rate inreases oxygen onsumption & metaboli rate [11] and other slow breathing exerises redue hemo reflex response to both hypoxia & hyperapnia but an inrease baroreflex sensitivity [12]. The heart rate is ontrolled by neural as well as other fators. Hene a derease in heart rate may be related to an inrease in vagal tone, a derease in ardia sympatheti ativity, as well as other non-autonomi fators. Pranayama have definite influene on sympatheti and parasympatheti innervations on modulation of the heart rate and the present study was aimed at analyzing heart rate related to the pratie of both Kapalabhati & Nadisuddhi pranayama to get a better understanding about the immediate effets of these praties on the autonomi status. 2. Materials and Methods The study was onduted in the Department of Physiology, Meenakshi Medial College, Kanhipuram, Tamilnadu. A total of 40 volunteers were seleted between the age group of 20-42 years. All of them were non smokers with sedentary lifestyle and free from major health problems. These volunteers were randomly subdivided into study group (n=20) and ontrol group (n=20). Study group volunteers were given training to learn and perform slow breathing exerises. They were instruted to perform slow breathing exerise for half an hour in the morning between 6 to 7 am and half an hour in the evening between 5 to 6 pm under the guidane of an expert. Various autonomi funtion tests were performed and the values were reorded before & after the study. The volunteers were instruted not to take tea, offee or any drinks before the reording.volunteers of ontrol group were not allowed to pratie slow breathing exerise. Autonomi funtion tests were arried out in both study & ontrol groups. The following autonomi funtion tests were performed, in aordane with the proedures desribed by Banister & Mathias [13,14]. The following tests were done: 2.1. Postural tahyardia index: - The subjets were asked to take rest in supine position for 2 minutes and to stand unaided and remain standing for about a minute while ECG was being reorded ontinuously. The heart rate response to standing is defined as the ratio between the heart rate at beat 15 after rising to the vertial position & the heart rate at beat 30. Longest R-R at 30th beat PTI = -------------------------------------- Shortest R-R at 15th beat A ratio of 1.00 or less was defined as an abnormal response, 1.01to1.03 as border line & 1.04 as normal response. 2.2. Deep breathing test The subjets of study group were asked to breathe deeply, steadily and slowly for 1minute at the rate of six breaths per minute, (5 seonds inspiration & 5 seonds expiration) while ECG was being reorded ontinuously. The heart rate hange with deep breathing was then expressed as the mean of the differene between maximal & minimal heart rate in 6 respiratory yles. Deep breathing differene = of heart rate differene in 6 breath yle Normal : Differene of 15 beats per minute or more. Borderline : Differene of 10 to 14 beats per minute. Abnormal : Differene of less than 10 beats per minute. 2.3. Heart rate response to Valsalva maneuver The subjets were trained to maintain an expiratory pressure of 40 mm of Hg for 10 seonds, a nose lip was applied and small air leakage inorporated in the mouthpiee to ensure that the expiratory pressure omes from the hest & that the subjet does not blow with the heeks. The subjets were made to pratie. The subjets were asked to blow out in the rubber tube of the merury manometer for 10 seonds while maintaining an expiratory pressure of 40 mm of Hg. ECG was reorded ontinuously during the valsalva manoeuver and for 30 seonds after release of pressure. ECG was reorded in standard limb lead II. Three readings were taken & the average was taken as a final reading. The Valsalva ratio (VR) was alulated as: Maximum RR distane after Valsalva maneuver V R = ------------------------------------------------------------ Minimum RR distane during Valsalva maneuver 3. Result and Disussion: The anient pratie of yoga makes use of voluntary regulation of breathing to make the respiration rhythmi & to alm the mind to reah the ultimate goal. This pratie of pranayama is an art of ontrolling the breath. A pratitioner of pranayama, not only tries to breathe properly but at the same time tries to keep his attention on the at of breathing, leading to onentration. This at of onentration removes his attention from worldly worries that distress him. This may derease the release of adrenaline. One of the benefiial effets of yogi exerise is to ontrol the autonomi nervous system and viseral funtions. So, the present study inludes the effet of pranayama breathing on autonomi nervous system and ardiovasular funtion. As the parasympatheti ativity funtion is more dominant on ardia funtion, the tests for parasympatheti funtion were seleted for this study [15-18]. Resting Heart rate was 74.5 beats per minute in study group and 79.85 in ontrols. These values were statistially signifiant. Similar responses were observed studied by G.K Pal et al [19].
1664 Resting Heart rate in ontrol and subjets Valsalva's Ratio in ontrol and subjets Resting heart rate(pulse/min) Valsalva Ratio error mean 74.5 79.85 6.477 7.862 1.448 1.758 1.1623 1.6610 0.63319 0.44541 0.01002 0.09960 COMPARISON OF RESTING HEART RATE IN GROUP I & GROUP II COMPARISON OF VALSALVA RATIO IN GROUP I& GROUP II 80.05 1.661 74.7 1.1835 I Heart rate response to Deep Breathing in ontrols and subjets Deep breathing test 16.4000 30.0000 1.0390 1.1460 5.67857 10.76055 0.01945 0.16766 0.89786 2.40613 0.00308 0.03749 P<0.05 P<0.05 Heart rate responses to standing in ontrol and subjets Postural tahy ardia index COMPARISON OF DEEP BREATHING TEST IN GROUP I&GROUP II 16.85 DBT 30 I COMPARISON OF POSTURAL TACHYCARDIAL INDEX IN GROUP I& GROUP II 1.0425 PTI 1.146 I Heart rate hanges depend on type of breathing exerises. Slow breathing exerises improve autonomi funtion; whereas fast breathing exerises do not alter autonomi funtion. Similar results were observed in the study of Bernardi et al.15 Khannam A et al [5]. studied the effet of yoga in asthma patients. Their study indiates derease in resting heart rate after yoga training. In normal resting subjet, the heart rate is determined mainly by bakground vagal ativity. The basal heart rate is therefore the funtion of parasympatheti system. In the present study, there was signifiant derease in basal heart rate in slow breathing group after three months of slow breathing exerise whih improves vagal ativity. 3.1. Deep breathing test I Deep breathing test indiates the mean differenes in heart rate during deep inspiration and deep expiration. The 'p' value is less than 0.05 whih indiates that findings are statistially signifiant. During inspiration, vagal ativity dereases and sympatheti ativity inreases. Therefore, the heart rate rises during inspiration. Opposite mehanism operate in expiration and heart rate dereases. This differene in heart rate in different phase of respiration is alled sinus arrhythmia [16]. This phenomenon of arrhythmia is aentuated in deep breathing. Deep breathing test response dereases with inreasing age [14]. Normally in adults the deep breathing test response varies from 10-15 and a value less than 10 is regarded as abnormal. A signifiant rise in deep breathing test response in slow breathing group in the present study indiates an inrease in vagal ativity. Pranayama slow breathing exerise inreases oxygen onsumption that improves autonomi funtions [11]. Also slow type of Pranayama breathing like Nadisuddhi breathing dereases sympatheti ativity and fast type of Pranayama breathing like Kapalabhati breathing inreases sympatheti ativity [10].The improvement of parasympatheti ativity following pratie of slow breathing exerise in present study may possibly be due to inreased
1665 oxygenation of tissues. As oxygenation does not improve in fast breathing due to inreased alveolar ventilation, no signifiant hange in autonomi ativity was observed in fast breathing group. Deep breathing test indiates the mean differenes in heart rate during deep inspiration and deep expiration. The 'p' value is less than 0.05 whih indiates that findings are statistially signifiant. During inspiration, vagal ativity dereases and sympatheti ativity inreases. Therefore, the heart rate rises during inspiration. Opposite mehanism operate in expiration and heart rate dereases. This differene in heart rate in different phase of respiration is alled sinus arrhythmia [16]. This phenomenon of arrhythmia is aentuated in deep breathing. Deep breathing test response dereases with inreasing age [14]. Normally in adults the deep breathing test response varies from 10-15 and a value less than 10 is regarded as abnormal. A signifiant rise in deep breathing test response in slow breathing group in the present study indiates an inrease in vagal ativity. Pranayama slow breathing exerise inreases oxygen onsumption that improves autonomi funtions [11]. Also slow type of Pranayama breathing like Nadisuddhi breathing dereases sympatheti ativity and fast type of Pranayama breathing like Kapalabhati breathing inreases sympatheti ativity [10].The improvement of parasympatheti ativity following pratie of slow breathing exerise in present study may possibly be due to inreased oxygenation of tissues. As oxygenation does not improve in fast breathing due to inreased alveolar ventilation, no signifiant hange in autonomi ativity was observed in fast breathing group. 3.2.Postural tahyardia index Postural tahyardia index indiate the baroreeptor reflex mehanism. The response is more in the study group 1.14± 0.16 and this hange is statistially signifiant. On immediate standing there ours an inrease in heart rate, whih reahes a maximum between 10th to 15th beat. Following this, the heart rate falls to a minimum in 1 to 2.5 minutes and then rises again to stabilize in 2.5 to 4 minutes [14]. In the present study, maximum inrease in heart rate is signifiantly less in subjets of slow breathing group. Our finding is similar to the observations of Bhargava et,al [1] that Pranayama breathing dereases base line heart rate and blood pressure by improving vagal tone and by dereasing sympatheti disharge[1]. However, other workers suggested that Pranayama breathing pratied exlusively in right nostril (right nostril pranayama) inreased sympatheti ativity [17,18]. It was also observed that left nostril breathing dereased sympatheti. 3.3.Valsalva ratio: Valsalva ratio indiates the integrity of sympatheti and parasympatheti pathways. Valsalva ratio values in ontrols were 1.16 ± 0.63 and in Subjets that its 1.66 ± 0.44. The 'p' value is less than 0.01 whih indiates statistially highly signifiant. During and after Valsalva manoeuver, hanges in the ardia vagal efferent and sympatheti vasomotor ativity our, resulting from stimulation of arotid sinus and aorti arh baroreeptors and other intrathorai streth reeptors [14]. Normally, this auses a sharp redution in venous return and ardia output & blood pressure falls. The effet on the baroreeptors is to ause a reflex tahyardia and to a lesser extent, peripheral vasoonstrition. With release of intrathorai pressure, venous return, stroke volume, and blood pressure rise to higher than normal levels. Parasympatheti influene then predominates and results in bradyardia. The above results indiate that parasympatheti ativity inreases and sympatheti ativity dereases in subjets doing regular slow breathing Pranayama exerises. 4. Conlusion The results of the present study in the Pranayama pratiing subjets indiate improvement in parasympatheti ativity on ardiovasular system. There was signifiant derease in basal heart rate in the study group pratiing slow breathing exerises whih indiates improvement in vagal ativity (vagal tone). It is evident from the present study that yoga develops an ability to ontrol ardiovasular autonomi funtion and an be presribed as an adjuvant therapy in ardiovasular diseases. 5. Referenes [1] Bhargava R, Gogate.MG, Masarenhas JF. Autonomi responses to breat holding and its variations following pranayama. Indian J Physiol Pharmaol 1988; 42:257-64. [2] Telles, Nagarathna R, Nagendra HR. Breathing through a partiular nostril an alter metabolism and autonomi ativities. Indian J Physiol Pharmaol 1994; 38:133-7. [3] Mohan M, Saravanane C, Surange SG, Thombre DP, Chakrabarthy AS. Effet of yoga type breathing on heart rate and ardia axis of normal subjets. Ind J Physiol Pharmaol. 1986; 30:334-40. [4] Bhattaharyya K S AND Krishna swami P. Trial of yogi exerise. Armed fores Med J 1960; 16:222-228. [5] Khanam.A, et, al. The study of pulmonary and autonomi funtions of asthma patients after yoga training. Indian journal of physiology and pharmaology, vol.40:318-324, 1996. [6] Swami Rama. Pranayama. The Royal Path: Pratial lessons on Yoga. The Himalayan Institute Press Honesdale, Pennsylvania. 1979; 55-70. [7] Bera TK AND Rajapurkar M V. Body omposition Cardio vasular endurane and anaerobi power of yogi Pratitioner. Indian J Physiol Pharmaol 1993; 37(3):225-228. [8] Funderburke J: Siene studies Yoga A review of physiologial data. Himalayan International Institute of Yoga sienes, Illinois, 1977. [9] Stanak AJ, Kuna M. Srinivasan, Vishnudevananda S, Dostalek C. Kapalabhati Yogi Cleansing exerise. 1. Cardiovasular and respiratory hanges. Homeost Health Dis 19991; 33(3): 126 134. [10] Raghuraj P, Ramakrishnan AG, Negendra HR, Talles S. Effet of two seleted yogi breathing tehniques of heart rate variability. Indian J physiol Pharmaol 1998; 42: 467 72. [11] Telles S, Desiraju T. Oxygen onsumption during pranayami type of very rate breathing. Indian J Med Res 1991; 94: 357 63. [12] Bernardi L, Gabutti A, Porta C, Spiuzza L. Slow breathing redues hemo reflex response to hypoxia and hyperapnia and inreases baroreflex sensitivity. J Hypertens 2001; 19: 2221 2229. [13] Grossman P. Respiratory and ardia rhyms as windows to entral and autonomi biobehavioral regulation: Seletion of window frames, keeping the panes lean and viewing the neural topography. Biol Psyhol.1992; 34: 131 161.
1666 [14] Bannister R, Mathias CJ. Investigations of autonomi disorders. Autonomi failure A text book of linial disorders of the autonomi nervous system, 3rd ed. San Fransison: Oxford University press; 1992 p. 255 90. [15] Bernaedi, et, al. Breathing patterns and ardiovasular autonomi modulation during hypoxia indued by stimulated altitude. J Hypertens.2001; 9 (5):947-958. [16] Ganong WF. Cardiovasular regulatory mehanism Review of medial physiology. 20th edition. San fransiso; MCGraw Hill; 2001 pp: 579-579. [17] Telles, Nagarathna R, Nagendra HR. Breathing through a partiular nostril an alter metabolism and autonomi ativities Indian J Physiol Pharmaol. 1994; 38:133-137. [18] Telles S, Nagarathna R. Nagendra HR.Physiologial measures of right nostril breathing. J Alternate ompl med. 1996; 2:479-484. Copyright 2010 BioMedSiDiret Publiations IJBMR - ISSN: 0976:6685. All rights reserved.