The effect of yoga on cardio-respiratory and physical efficiency of the healthy subjects
Dr Neeraj Mahajan1 Dr Pawan Goyal2 Dr Jinal Pandya3
1 Associate Professor, Department of Physiology, Smt. NHL Municipal Medical College, Ahmedabad, Gujarat.
2 Associate Professor, Department of Physiology, Govt Medical College, Silvassa, Dadra & Nagar Haveli (UT).
3Assistant Professor, Department of Physiology, Dr M. K. Shah Medical College & Research Center, Ahmedabad
Correspondence to: Dr Pawan Goyal, E-mail: [email protected]
Abstract:
Background and Objectives: yoga as an exercise regime improves the physical and mental wellbeing in humans. Regular practice of yoga has positive impact on vital parameters of an individual. However data pertaining to effect of yoga on cardio respiratory parameters in south Gujarat region is least available. Hence, this study was undertaken to find out the effects of yoga on cardio respiratory parameters in healthy subjects in south Gujarat region. Material and Method: this study was conducted on age matched healthy individuals (n=80) with age group 25-60 years. They were divided into control group (n=40) and yoga group (n=40). Yoga intervention was given to yoga group for 10 weeks continuously. Weight, chest girth, chest expansion, PR, BP, RR, TV, BHT, VC, Expiratory pressure, PFI and Work done were measured in both the groups before and after the yogic intervention. Data was compared by using chi square test. P value was established at <0.05 for the statistical significance. Result: significant (P<0.05) improvement was noted in cardio respiratory parameters, PFI and work done than their respective baseline values. Further, changes in weight, chest girth and chest expansion were observed to be nonsignificant compared to their baseline values. Conclusion: This study shows that yogic practices promote and improve respiratory and cardiovascular function and enhances physical fitness.
Key words: Yoga, Blood pressure, Pulse rate, Tidal volume, Breath holding time, Physical fitness index.
Introduction
Yoga comes from the sanskrit word Yug which means union, specifically the union of mind, body and spirit. Originating in Tibet and India over 3,000 years ago, Yoga is one of the worlds oldest branches of spiritual inquiry and physical exploration. Yoga is described as a path for transcending the ordinary mind (who you think you are) in order to merge with your Higher self. Yogic postures are specifically devised to endow the vital organs to function without giving fatigue to the muscles.
In recent years a lot of research studies have shown that Yoga can be useful not only in prevention, control and rehabilitation of many diseases7,16 but also in acute cases of asthma15. Yoga techniques reduce anxiety and depression13 keeping the body supple, fit and strong. It also gives a feeling of well-being. Yoga helps by increasing oxygen supply to the brain, improving memory and increasing ability to focus attention for long periods.
This work is being undertaken to find out The effect of Yoga on cardio-respiratory and physical efficiency of the subjects.
In recent years, the benefits of Yoga are being more and more realized and used in prevention, control and rehabilitation of many diseases, and in physical training of players and athletes in many parts of the world. Yoga study is becoming more and more popular among people and scientists all over the world. Many generations of very hard working, sincere and devoted yogis have divulged the knowledge and techniques of yogic practices to the scientific world today. It is necessary that medical science in particular should pay due attention to the investigations of Yoga.
It is evident now that stress and strain are definite factors in the etiology of several chronic diseases. Yoga therapy could form the basis of prevention and permanent cure of these psychosomatic problems. Yoga is a system of exercises by means of which the person develops resistance towards stress and strain. Regular practice of Yoga is one of the best forms of relaxation.
Material and Methods
This study was conducted on 80 healthy subjects with age group of 25 to 60 years, out of which 40 subjects were given yoga intervention by performing regular yogasanas at Aeroyog, Dreamland arcade – 2nd Floor – 204, Tithal Road, Valsad, Gujarat under the guidance of a Yoga instructor continuously for 10 weeks, and rest 40 subjects were selected as control group.
This study was approved by institutional ethics committee of GMERS Medical College, Valsad. An informed written consent was taken from all the subjects.
All the subjects were examined twice, first immediately before they started Yoga practice and then after ten weeks of Yoga practice. Height, Weight and Chest measurement were taken for both groups. Cardiac parameters like Pulse rate, Blood pressure (Systolic and Diastolic blood pressure) and fitness index was calculated using Harvard step test. Respiratory parameters like Tidal volume, Vital Capacity, Respiratory rate, Breath holding time and Expiratory pressure were recorded in both the groups.
All the candidates, except control cases, performed Yoga asanas daily in the morning hours from 6.00 to 7:30 am at the Yoga centers, under the supervision of qualified Yoga instructors, for a period of 10 weeks.
Yoga exercises included: Surya Namaskar for 8 minutes, Sharir Sanchalan for 15 minutes, Asanas (Padmasana, Sarvangasana, Vajrasana, Halasana, Chakrasana, Dhanurasana, Bhujangasana, Ardha Paschimottanasana, Matsyasana) for 40 minutes followed by Pranayam for 25 minutes and Prayer for 2 minutes.
Observation and Results
Table – 1: comparative study of physical examination between control and yoga group.
Sr. No. Examination Control Group
Mean with S.D. Effective
I II P Value Yoga Group
Mean with S.D. Effective
I II P Value
1.
2.
3. Weight (Kg.)
Chest Girth (Cm.)
Chest Expansion(cm.) 63.600
+ 8.182
85.073
+3.049
3.367
+1.488 64.053
+8.679
85.113
+3.062
3.400
+1.409 0.8840
0.9716
0.9502 65.320
+ 9.886
87.170
+8.009
3.570
+1.324 64.713
+ 9.902
86.683
+8.232
3.657
+1.205 0.8131
(insignificant)
0.8172
(insignificant)
0.7918
(insignificant)
Table – 2: Comparative study of cardiac parameters
Sr. No. Examination Control Group
Mean with S.D. Effective
I II P Value Yoga Group
Mean with S.D. Effective
I II P Value
1.
2.
3. Pulse Rate
( / min. )
Blood Pressure Systolic (mmHg)
Blood Pressure Diastolic
(mmHg) 78.533
+ 8.391
128.933
+8.102
81.733
+4.301 78.867
+ 7.140
128.400
+6.685
81.333
+ 5.014 0.9075
0.8455
> 0.05 80.067
+ 7.292
129.400
+10.842
82.600
+6.371 70.633
+ 5.209
116.733
+ 6.977
76.200
+5.182 < 0.001
(significant)
< 0.001
(significant)
< 0.001
(significant)
Table – 3: Comparative study of respiratory parameters.
Sr. No. Examination Control Group
Mean with S.D. Effective
I II P Value Yoga Group
Mean with S.D. Effective
I II P Value
1.
2. Respiratory rate ( / min.)
Tidal Volume
( ml.) 16.867
+ 2.924
418.333
+ 78.755 17.000
+ 2.726
420.000
+ 74.522 0.8981
0.9529
17.267
+ 2.363
437.500
+ 91.385 13.900
+ 1.470
459.333
+ 83.982 < 0.001
(significant)
0.3392
(insignificant)
Table – 4: Comparative study of respiratory efficiency parameters.
Sr. No. Examination Control Group
Mean with S.D. Effective
I II P Value Yoga Group
Mean with S.D. Effective
I II P Value
1.
2.
3. Breath Holding time (sec.)
Vital capacity
( ml)
Expiratory Pressure(mmHg) 41.733
+ 5.625
2416.667
+ 348.039
82.400
+ 15.733 41.200
+ 5.441
2390.000
+ 343.927
81.733
+ 14.079 0.7937
0.8343
0.9035 44.467
+ 12.199
2580.000
+ 477.800
73.667
+ 13.275 61.267
+ 14.029
2936.667
+ 442.258
81.400
+ 14.794 < 0.001
(significant)
< 0.05
(significant)
< 0.05
(significant)
Table – 5: Comparative study on cardiac and physical efficiency parameters.
Sr. No. Examination Control Group
Mean with S.D. Effective
I II P Value Yoga Group
Mean with S.D. Effective
I II P Value
1.
2.
Harward step test (%)
Work done
by cycle ergometer
(kg-m2 ) 77.800
+ 11.156
509.267
+ 179.559 76.933
+ 10.512
542.667
+ 206.906 0.8282
0.6404 75.600
+ 9.717
520.000
+ 188.990 82.167
+ 9.717
766.033
+ 251.365 < 0.05
(significant)
< 0.001
(significant)
Discussion
In Table no. 1 we observed that after 10 weeks of yogic exercise there was nonsignificant change in the mean value of body weight. (P value – 0.813), Chest girth (P value – 0.8172) & Chest expansion (P value – 0.7918). Similarly the control group also did not show any significant change in these parameters. Another study by Nayar et al9 also found that there is nonsignificant change after 6 months of Yoga. While Makwana and associates12 observed significant fall in weight, but only in over weight subjects (P < 0.005) after 2 months of Yoga practice but chest girth and chest expansion did not show significant improvement. Udupa et al19 in his study showed that Shirshasana, Bhujangasana, Shalbhasana and Mayurasana lead to reduction in weight and significant increase in chest girth and chest expansion in his study after 6 months of Yoga practice.
In table no 2 Yoga group showed significant decrease in pulse rate (P<0.001), Systolic blood Pressure (P < 0.001) and Diastolic blood Pressure (P < 0.001). In the control group, the change was insignificant (P<0.907). Study conducted by Khanna AA et al11 also observed significant fall in resting pulse rate and Blood Pressure in 9 asthmatics following Yoga (P<0.05). Our readings also match with the study of Bowman A. J. and his associates4, Telles et al18, Makwana and colleagues12 Mohan M et al14, Nayar and associates9 etc. Change in pulse rate is mediated through the conditioning effects of Yoga practices on autonomic nervous system and through limbic system1.
Table no 3 showed respiratory rate in the Yoga group fell from mean value of 17.26 + 2.3 to 13.9 + 1.4 (P<0.001) while the control group did not show significant changes. Our observations matched with similar studies10, 12, 19, 23. While in one study9 they did not find any changes in respiratory rate. A possibility is that Yoga practitioners have more tidal volume than the non-yogic persons and thereby fulfill the total O2 demand of body even by low rate of respiration.
Tidal volume did not show significant changes in both the groups. (P > 0.05). Similarly Sachdeva et al17 and Makwana and associates12 also recorded insignificant changes in tidal volume of Yoga practitioners while Gopal Bhatnagar et al8 recorded a significant increase in tidal volume after 6 months of Yoga practice.
Table no 4 showed Breath Holding Time, Vital capacity and Expiratory pressure in the Yoga group was found to have increased significantly. Similar observations were recorded in other studies10,12,2,19,9,5,8,22.
The cause of increased vital capacity can be explained improved patency of airway partly due to increased development of respiratory musculature is incidental to regular practice of yogic exercises 22,9. In some yogic exercises, short powerful strokes of exhalation in quick succession, train the subject to make full use of the diaphragm and abdominal muscles in breathing. It also helps in the removal of secretion from bronchial tree, clearing up the respiratory passage and the alveoli, making room for more air. Pranayam on the other hand is characterised by slow and deep inhalation and exhalation. The stress is on prolonged expiration and an efficient use of abdominal and diaphragmatic muscles. This act trains the respiratory apparatus to get emptied and filled more completely and efficiently. Some types of yogic breathing create negative pressure in abdominal and thoracic cavity,3 raising the diaphragm at a higher level than its normal excursion. Due to removal of undue tension from the skeletal muscles in yogic exercises, the thorax relaxes better than before2.
In table no. 5 Fitness index as assessed by Harward step test showed improvement in the Yoga group. (P<0.05). Our observation matched with similar studies12, 17.
The work done was calculated by bicycle ergometry. In the Yoga group it increased from mean value of 520.00 + 188.9 to 766.03 + 251.3 (P<0.001) 19 while the control group, it did not show any significant improvement.
Conclusion
This study concludes that yogic exercises have a great value in improving cardio respiratory efficiency, general health and physical fitness. Its role in prevention, control and rehabilitation of many diseases is also beyond any doubts. Yoga should be popularized amongst general public as a health promoting measure. But still there is much scope of further study to evaluate specific asanas for improving specific parameters.
References
Anand BK, Chinna GS Investigations on yogic claiming to stop their heart beat. Ind. J. Med. Res. 49 : 90, 1961.
Bhole MV, Karmbelkar PV. Effect of Yoga training on vital capacity and breath holding time. Yoga Mimansa 14 : 19, 1971-72
Bhole MV, Karmbelkar PV, Choroto ML. Effect of Yoga practice on vital capacity. Ind. J. Chest Dis. 12 (1982) 1, 19.
Bowman AJ, Murray A, Effects of aerobic exercises training and Yoga on baroreflex in healthy elderly persons. Eur J. Clin Invest (England) May 1997 27 (5) P 493 9
Brahmachari Chowdhary, Mittimoha. Short-term Yoga practice and changes in body functions in young healthy individuals. Ind. J. Phy. and Pharm. 24 (5) Suppl. 1: 459, 1980
Brownstein AH, Dembert MV, T/t of essential HT with Yoga relaxation therapy in USSR Avian space
Environ Med. (USA) Jul. 1989 60 (7) P 684 7
Collins C, Yoga intuition preventive medicine and treatment J obstel Gynecol neonatal nurs (USA) SepOct. 1998 (27)(5) P563 8
Gopal KS, Bhatnagar OP, Subramanian N, Nishith SD. Effect of yogasans and pranayamas on blood pressure, pulse rate and respiratory functions. Indian J Physiol Pharmacol, 1973; 17: 273-76.
HS Nayar, Mamur R.M, Sampat Kumar. Effect of yogic exercise on human physical efficiency. Ind. J. Med. Res. 63:7369, 1975.
Joshi LN, Joshi VD, Effect of short term Pranayam practice on breathing rate and ventilatory functions of lungs. IJPP (India) Apr. 1992 36 (2) P 105 8
Khanam AP, Sachdeva V, Deepak KK. Study of pulmonary and autonomic function of Asthma pts. after Yoga training. Indian J physio Phermacol (India) Oct. 1996 40 (4) P 138 24
Makwana K, Khirwadkar N, Gupta HC. Effect of short term Yoga practice on ventilatory function tests. IJPP (India) Jul. Sep. 1988 32 (3) P 202 8
Malathi A, Damodoran A, Stress due to exams in medical student – role of Yoga. Indian J physio pharmaco (India) Apr. 1999 43 (2) P 218 24
Mohan M, Sara Vanane C, Effect of Yoga type breathing on heart rate and Cardiac-axis of normal subjects. JPP Oct-Dec. 1986 30 (4) P 334 40
Nagarathan R, Nagendra HR. Yoga for br. Asthma a, a controlled study. British Medical Journal 1985 291 1077 1075
Naveen KV, Telles S. Yoga for rehabilitation an overview V.K. Yoga research foundation Bangalore India. J Medical sci. (India) Apr. 1997 (4) P 123 7
Sachdeva, Chinna, Singh. Effect of yogic training on some of the cardio respiratory functions. Ind. J. Phy. and Pharma. 24 (5): Suppl. 1: 1980
Telles S. Plasticity of motor control system demonstrated by Yoga training. India J Physio pharmacol (India) Apr. 1994 38 (2) P 143 – 4
Udapa KN, Singh R. H. Scientific basis of Yoga. J.A.M.A. 220: 1365,1972.
Akhtar P, Yardi S, Akhtar M. Effects of yoga on functional capacity and well being. International journal of yoga. 2013 Jan;6(1):76.
Doijad VP, Kamble P, Surdi AD. Effect of Yogic exercises on aerobic capacity (VO2 max). International journal of physiology. 2013;1(2):47-50.
Cadore EL, Rodr?guez-Ma?as L, Sinclair A, Izquierdo M. Effects of different exercise interventions on risk of falls, gait ability, and balance in physically frail older adults: a systematic review. Rejuvenation research. 2013 Apr 1;16(2):105-14.
Waghmare P, Baji PS. Effect of pranayama on cardio-respiratory efficiency. Indian Journal of Basic & Applied Medical Research. 2013 Sep;8(2):918-22.
Ross A, Friedmann E, Bevans M, Thomas S. National survey of yoga practitioners: mental and physical health benefits. Complementary Therapies in Medicine. 2013 Aug 1;21(4):313-23.
Lau C, Yu R, Woo J. Effects of a 12-week hatha yoga intervention on cardiorespiratory endurance, muscular strength and endurance, and flexibility in Hong Kong Chinese adults: a controlled clinical trial. Evidence-Based Complementary and Alternative Medicine. 2015;2015.
Mahajan N, Ashok S, Patel K, Aparna P. Yoga as an exercise tool: study of physiological parameters of the healthy subjects. Int. J Basic Appl. Physiol. 2016;5(1):54.
Desai R, Jasani K, Verma A, Prajapati RB. Comparative study of effect of yoga and meditation on cardio-respiratory efficiency and mental well-being. Int J Basic Appl Physiol. 2016;5(1):114.
Udhan VD, Wankhede SG, Phatale SR. Effect of Yoga on Cardio-Respiratory Health Markers: Physical Fitness Index and Maximum Oxygen Consumption (VO 2 Max). Journal of Clinical & Diagnostic Research. 2018 Aug 1;12(8).