International Journal of Yoga

SHORT COMMUNICATION
Year
: 2015  |  Volume : 8  |  Issue : 2  |  Page : 134--138

Positive effect of yoga on cardiorespiratory fitness: A pilot study


Eliška Sovová1, Vít Cajka1, Dalibor Pastucha1, Jana Malincíková1, Lenka Radová2, Markéta Sovová3,  
1 Department of Exercise Medicine and Cardiovascular Rehabilitation, Faculty of Medicine and Dentistry Palacky University Olomouc, University Hospital Olomouc, Czech Republic
2 Central European Institute of Technology, Masaryk University, Brno, Czech Republic
3 Department of Internal Medicine II - Gastroenterology and Hepatology, Faculty of Medicine and Dentistry Palacky University Olomouc, University Hospital Olomouc, Czech Republic

Correspondence Address:
Eliška Sovová
Department of Exercise Medicine and Cardiovascular Rehabilitation, Faculty od Medicine and Dentistry Palacky University Olomouc, University Hospital Olomouc
Czech Republic

Abstract

Introduction: Cardiovascular disease (CVD) is the leading cause of death in developed countries. An integral part of primary prevention is physical activity. One form of physical activity to be potentially used is yoga, but this activity is associated with lower energy expenditure than that recommended for prevention. The study aimed at assessing the effect of regular yoga sessions on the aerobic capacity of the practitioners and comparing it with the normal population performing physical activity recommended by guidelines. Materials and Methods: Fifty-eight persons (16 males) with a mean age of 50.0 ± 11.06 years comprising the yoga group practiced yoga for at least 1 h a day for over 2 years. They underwent spiroergometry under maximal exercise testing to assess basic performance parameters. Their results were compared with those in 54 age-matched controls (16 males mean age of 48 ± 11.86 years performing a regular aerobic physical activity for at least 7 h a week. Results: The yoga group had statistically significantly higher maximum performance per kilogram (P = 0.007) and maximum oxygen consumption per kilogram per minute (P = 0.028). Conclusions: Despite low energy expenditure, yoga practices are better in some cardiorespiratory fitness parameters than other aerobic activities recommended by current guidelines for CVD prevention.



How to cite this article:
Sovová E, Cajka V, Pastucha D, Malincíková J, Radová L, Sovová M. Positive effect of yoga on cardiorespiratory fitness: A pilot study.Int J Yoga 2015;8:134-138


How to cite this URL:
Sovová E, Cajka V, Pastucha D, Malincíková J, Radová L, Sovová M. Positive effect of yoga on cardiorespiratory fitness: A pilot study. Int J Yoga [serial online] 2015 [cited 2019 Sep 19 ];8:134-138
Available from: http://www.ijoy.org.in/text.asp?2015/8/2/134/158482


Full Text

 INTRODUCTION



Cardiovascular disease (CVD) is the leading cause of death and disability in all developed countries. An integral part of primary prevention mainly focusing on modifiable risk factors is physical activity. [1] One form of physical activity to be potentially used is yoga, a system of physical practices and breathing techniques aimed at achieving better health and inner balance. These activities are recommended, for instance, in guidance provided by the American College of Sports Medicine. [2]

Worldwide, studies have been published that document the beneficial effect of regular yoga exercises on human health. Innes et al. [3],[4] repeatedly carried out a meta-analysis of literature regarding the effects of yoga on indices of CVD risk associated with insulin resistance and suggested beneficial changes in blood pressure, abdominal obesity, lipid and coagulation profiles, oxidative stress, sympathetic activation, improved risk profiles in adults with type 2 diabetes mellitus, and several clinical endpoints. These findings were confirmed by other authors as well. [5]

On the other hand, Lau et al. [6] conducted a meta-analysis of studies in 2012 that would confirm the effectiveness of yoga for secondary prevention of CVD. In the main databases, they found no eligible randomized controlled trials meeting the inclusion criteria (at least a 6-month follow-up period, patients diagnosed with CVD, studies comparing a group practicing yoga and controls receiving no intervention or interventions other than yoga).

Ray et al. [7] studied 20 males during Hatha Yoga practices (asanas/postures and breathing maneuvers) and found that their metabolic rate was in the range of 1-2 metabolic equivalents (MET) except in three asanas (>2 MET). Similarly, Hagins et al. [8] concluded that yoga sessions represent low levels of physical activity (a mean MET value across a session of 2.5) and do not meet recommendations for levels of physical activity for improving cardiovascular fitness. Thus, the question is whether mere practicing of yoga with low energy expenditure could be recommended for disease prevention.

The study aimed at assessing the effect of regular yoga sessions based on the system Yoga in Daily Life on aerobic capacity (cardiorespiratory fitness) of the practitioners and comparing it with the normal population performing physical activity as recommended.

 Materials and Methods



Participants

A total of 58 persons comprising the yoga group (16 males and 42 females) with a mean age of 50.0 ± 11.06 years (range, 31-70 years;) were examined. The inclusion criterion was to practice yoga in accordance with the system Yoga in Daily Life for at least 1 h a day for over 2 years (it response with Guidelines given by American Heart Association). Yoga in Daily Life is built on the principles of traditional Indian yoga and adapted to the modern lifestyle (relaxation, asanas…).

The control group comprised of 54 individuals (16 males and 38 females) with a mean age of 48 ± 11.86 years (range, 25-70 years). The controls were selected from patients registered at our department and randomly matched. The inclusion criterion was a regular aerobic physical activity performed for at least 7 h a week (brisk walking, jogging, cycling, dancing). The two groups were matched for age (P = 1.0) and gender (P = 0.837).

Exclusion criterion was a rejection of participation in the study.

 Design



The clinical evaluation consisted of taking histories and conducting physical examinations, including weight and height measurements with calculation of body mass index (BMI kg/m 2 ).

In both groups, maximal exercise testing was performed on the Oxycon Plus system-Jaeger, in a well-ventilated, temperature- and humidity-controlled room. The system was calibrated before each test. Exhaled gases were analyzed using the breath-by-breath method (a facemask). The exercise tests were carried out on a bicycle ergometer (Ergoline 600).

All participants were fasting for 12 h overnight. The protocol started with a 3-min workload of 1 W/kg and was followed by an incremental ramp protocol to a subjective maximal effort (a test duration of up to 12 min). [9] From all participants, a signed written informed consent was obtained.

 Assessments



The following parameters were investigated: Resting heart rate (HR rest ), resting blood pressure (BP rest ), maximum heart rate (HR max ), blood pressure at maximum exertion, maximum performance (W max /kg), maximum oxygen consumption per kilogram per minute (VO 2max /kg/min), maximum metabolic equivalent (MET max ), maximum minute ventilation (V Emax ), VCO 2max , maximum carbon dioxide production, and respiratory exchange ratio (RER).

 Data analysis



Statistical analyses were done using software Statistica 12 (Dell Softwares, StatSoft, Inc.). The Mann-Whitney U-test was used to evaluate differences in all clinical variables between both groups. The logistic regression was applied in the case of adjustments for weight and BMI. The level of significance was set at P = 0.05.

 RESULTS



Results for the entire cohort, males and females are shown in [Table 1] and [Table 2].{Table 1}{Table 2}

The yoga group had statistically significantly higher HR max , W max /kg, VO 2max /kg/min, and MET max and statistically significantly lower body weight, BMI, BP rest , V Emax , VO 2max , and VCO 2max .

After the cohort was divided into males and females, the statistically significant differences between the categories varied. In case of males, the yoga group had statistically significantly lower body weight, V Emax and VO 2max and in females statistically significantly lower body weight, HR rest , systolic and diastolic BP rest and VO 2max . The female yoga practitioners had statistically significantly higher HR max , W max /kg, VO 2max /kg/min, MET max , and RER.

In both groups, the mean performance parameters (W max /kg and VO 2 max /kg/min) were normal when compared with charts for the general population.

Given the differences in body weight and BMI between the two groups, the results were adjusted for BMI. [Table 3] shows that the yoga group has statistically significantly higher W max /kg and VO 2max /kg/min despite lower V Emax , VO 2max , and VCO 2max .{Table 3}

 Discussion



The present study showed that the group practicing the Yoga in Daily Life system had better aerobic performance than controls performing other aerobic physical activity for the same amount of time per week. Thus, it may be concluded that in spite of low energy expenditure during sessions, yoga has a positive effect on individuals' aerobic performance.

The results are consistent with data from Chen et al. [10] reported a positive influence of Silver Yoga exercises on physical fitness (e.g., body composition, cardiovascular-respiratory functions or body flexibility).

Not surprisingly, the yoga group had a statistically significantly lower body weight and BMI. This is associated not only with taking regular exercise (its duration was identical in both groups) but especially with dietary habits as most yoga practitioners prefer healthy, preferably vegetarian, foods. [11]

Physical performance improvement is possible owing to both better economy of breathing and improvement in cardiovascular reserve, with other factors such as psycho-physiological and better relaxation possibly contributing. [7]

In the present study, yoga was more beneficial for females, in whom it was also shown to influence HR rest and/or BP rest . The main mechanisms behind lower BP rest are likely to be parasympathetic predominance, increased baroreflex sensitivity and decreased the arterial tone and peripheral resistance. [12]

The present study failed to show an effect of yoga on exertional blood pressure. There is no study available on this issue.

After adjustment for BMI, the impact of yoga on the main cardiovascular performance parameters was confirmed in both males and females. The differences between males and females should be verified in future studies with more participants.

The mean age of participants in the present study was 48 years, similar to the mean age of females in a study by Ramos-Jiménez et al. [13] reporting a positive effect of 11-week intensive Hatha Yoga program on V Emax and VO 2 max .

In the present study, the Yoga in Daily Life system was applied. This may not be expected to result in better performance. For instance, in a recent study by Akhtar et al., [14] 30 physiotherapy students volunteered to undergo a baseline 6-min walk test, followed by thirty 1-h yoga sessions (yogic asanas/postures for 30 min, pranayamas/breathing for 15 min, omkar chanting for 10 min, and shavasana/relaxation for 5 min) over 6 weeks. Another 6-min walk test after the yoga intervention showed statistically significant improvements in walk distance, rating of perceived exertion and recovery time.

Similarly, Parshad et al. [15] investigated the impact of yoga on hemodynamic function in healthy medical students and found its improvement after 6 weeks of practice comprising asanas/postures, pranayamas/breathing, and dhyana/meditation.

The present study is mainly limited by small subject numbers; however, other studies reported in the literature are of similar sizes. The second limitation is the wide range of age. The study was not prospective, mainly because of complicated methods associated with performing such studies affected by inadequate participants' compliance. Ideally, a large international multicenter study concerned with the topic should be organized.

 CONCLUSION



Despite low energy expenditure, yoga practices are better in some cardiorespiratory fitness parameters than other aerobic activities recommended by current guidelines for CVD prevention.

 ACKNOWLEDGMENTS



Supported by RVO 61989592.

References

1Perk J, De Backer G, Gohlke H, Reiner Z, Verschuren WM, Albus C, et al. European Guidelines on Cardiovascular Disease Prevention in Clinical Practice; 2012. Available from: http://www.sciencedirect.com/science/article/pii/S0021915012002882.
2Garber CE, Blissmer B, Deschenes MR, Franklin BA, Lamonte MJ, Lee IM, et al. American College of Sports Medicine position stand. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: Guidance for prescribing exercise. Med Sci Sports Exerc 2011;43:1334-59.
3Innes KE, Bourguignon C, Taylor AG. Risk indices associated with the insulin resistance syndrome, cardiovascular disease, and possible protection with yoga: A systematic review. J Am Board Fam Pract 2005;18:491-519.
4Innes KE, Vincent HK. The influence of yoga-based programs on risk profiles in adults with type 2 diabetes mellitus: A systematic review. Evid Based Complement Alternat Med 2007;4:469-86.
5Yang K. A review of yoga programs for four leading risk factors of chronic diseases. Evid Based Complement Alternat Med 2007;4:487-91.
6Lau HL, Kwong JS, Yeung F, Chau PH, Woo J. Yoga for secondary prevention of coronary heart disease. Cochrane Database Syst Rev 2012;12:CD009506.
7Ray US, Pathak A, Tomer OS. Hatha yoga practices: Energy expenditure, respiratory changes and intensity of exercise. Evid Based Complement Alternat Med 2011;2011:241294.
8Hagins M, Moore W, Rundle A. Does practicing hatha yoga satisfy recommendations for intensity of physical activity which improves and maintains health and cardiovascular fitness? BMC Complement Altern Med 2007;7:40.
9Balady GJ, Arena R, Sietsema K, Myers J, Coke L, Fletcher GF, et al. Clinician's Guide to cardiopulmonary exercise testing in adults: A scientific statement from the American Heart Association. Circulation 2010;122:191-225.
10Chen KM, Fan JT, Wang HH, Wu SJ, Li CH, Lin HS. Silver yoga exercises improved physical fitness of transitional frail elders. Nurs Res 2010;59:364-70.
11Èajka V, Sovová E, Pastucha D, Benusov I, Doupalova P, Zapletalova J. Life style analysis of yoga exercisers in comparison with the general population. Prakt Lék 2013;6:260-3.
12Raub JA. Psychophysiologic effects of Hatha Yoga on musculoskeletal and cardiopulmonary function: A literature review. J Altern Complement Med 2002;8:797-812.
13Ramos-Jiménez A, Hernández-Torres RP, Wall-Medrano A, Muñoz-Daw MDj, Torres-Durán PV, Juárez-Oropeza MA. Cardiovascular and metabolic effects of intensive Hatha Yoga training in middle-aged and older women from northern Mexico. Int J Yoga 2009;2:49-54.
14Akhtar P, Yardi S, Akhtar M. Effects of yoga on functional capacity and well being. Int J Yoga 2013;6:76-9.
15Parshad O, Richards A, Asnani M. Impact of yoga on haemodynamic function in healthy medical students. West Indian Med J 2011;60:148-52.