Review

Exploring the Health Benefits of Yoga: A Review

¹Theresa A. Schreiber, ¹Brandi S. Niemeier

• ¹Department of Health, Physical Education, Recreation & Coaching, University of Wisconsin-Whitewater, 130 Williams Center, 800 West Main Street, Whitewater, WI 53190

• Submitted: December 27, 2012
• Accepted: January 11, 2013
• Published: March 1, 2013

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Introduction

It has been suggested that yoga can lead to enhanced productivity and increased quality of life. The aim of this study is to investigate the health benefits of yoga across several dimensions of wellness. Yoga is explored in a physiological context as an exercise form, and the potential of yoga as a continued source of complementary and alternative medicine (CAM) in Western culture is broadly discussed.

Study Design

A review of current literature was conducted to portray the health benefits of yoga.

Material and Methods

Related studies published between 2000 and 2012 were accessed via EBSCOhost. Multiple study forms were coalesced.

Results

Published studies of yoga are scarce. Thirteen publications met the selection criteria and were included in this review. The focus of the literature is on yoga as exercise and its impact on health and wellbeing. Yoga is a unique form of physical fitness; it is a multidimensional approach used to achieve elevated levels of health or wellness. When used as a form of CAM, yoga has shown healing properties in ameliorating various symptoms of chronic conditions.

Conclusions

Yoga is a useful supplement to traditional medicine when integrated as part of a holistic health routine; however, current literature is limited. Additional research on the health benefits of yoga is warranted, and replications using various populations are needed to substantiate health claims in current literature.

Keywords

yoga, wellness, wellbeing, exercise, complementary and alternative medicine.

Introduction

As part of Hindu culture, the lineage of yoga dates back 3000 years. Traditional yogic practices have been translated from the ancient Sanskrit language. The original teachings of Patanjali helped shape the philosophy of yoga, much of which is still preserved to present day. Today, Patanjali is credited as being the “father” or founder of yoga. The authentic practice of yoga is comprised of Eight Limbs, or eight guiding principles. Physical asana practice, the “yoga” understood by Westerners, is just one of these eight principles. Historically, and presently, yoga is seen as mind-body medicine. The health benefits of yoga practice, as will be explored in the current study, extend greatly beyond that of other traditional exercise forms.

Present day, yoga boasts over 15 million avid American practitioners [1,2], each with their own intentions for doing yoga. This rapidly growing figure of yoga “groupies” consists of 7.5% of the current U.S. adult population [1]. Yoga is quickly becoming a go-to form of mind-body fitness. With its growing popularity, yoga has established itself as one of the top five mind-body medicines within the United States [3]. Today, yoga is considered as an alternative exercise approach to obtain personal health and wellbeing. Yoga’s holistic methodology strives to unite one’s body, mind, and spirit; it is a method of exercise mirrored in the physical, mental, and emotional benefits which result. This practice extends well beyond the yoga mat, with some now categorizing yoga as a health behavior or lifestyle choice [1, 4].

The practice of yoga that has been widely embraced in the West is comprised of four essential components: asana or physical postures, pranayama or breathing technique, dhyana or meditation, and savasana or relaxation [1, 5, 8]. The branch of yoga with which Americans are most familiar is known as Hatha yoga. Hatha yogic style consists of the integration of these four practice features.

Yoga is in a state of growth as a form of exercise, yet the current research on the health benefits of yoga is limited in its presentation. The purpose of the current study is to explore the various health benefits of yoga while also considering other exercise forms. The aim is to uncover yoga’s holistic approach to exercise and its potential as a complementary alternative option within healthcare.

Material and Methods

A literature search was conducted using EBSCOhost (www.search.ebscohost.com) with the following search terms: (yoga and health); (yoga and exercise); (yoga and wellness); and (yoga and wellbeing). Inclusion criteria for related research articles follow:

• Publication Date Range—2000 to 2012.
• Article Source—Peer-reviewed professional journals.
• Content—Relationship of yoga to any dimension of personal wellbeing and exercise.

Multiple study types were included in this review, including controlled and uncontrolled studies, cross-sectional and longitudinal studies, case studies, and other literature reviews.

Results

Thirteen studies met the selection criteria and were included in this study. A range of therapies and benefits of yoga were revealed in addition to barriers and limitations of yoga.

Styles of Yoga

The important linkage between the mind and the body is understood now better than ever before, and researchers have long questioned the effect of this symbiotic relationship on personal health. Smith et al., [2], for example, sought to uncover the cumulative and holistic benefits of yoga by comparing the physiological health effects of an integrative yoga practice versus purely physical yoga practice. Smith and colleagues evaluated 81 participants each divided into three groups: the first an integrative yoga group, the second a yoga-as-exercise group, and the third a control group (questionnaire only). All participants experienced elevated levels of depression, stress, or anxiety prior to the study. The integrative classes featured an ethical, spiritual, and meditative theme rooted in Eastern yogic tradition, while the exercise yoga classes did not. The exercise yoga group featured a solely physical practice, comprised of a series of postures or asanas. Interestingly, in cross-comparison, only the results for the integrative yoga group showed a decrease in salivary cortical and, subsequently, a decrease in their level of anxiety.

Anxiety and its relative, stress, both play critical roles in the onset of disease [9]. The research presented by Smith and colleagues [2] prominently contends yoga’s ability to reduce anxiety and stress. This research suggests that via integrative technique, yoga has promising potential to combat disease initiators, thus contributing to overall health. Advocates for yoga support an increased reliance on this method as a route to ward off potential illness.

Several subcategories of yogic styles exist under the overarching “Hatha yoga” term, each style with subtle variances in means. Intensity is just one of the exercise components that vary among types of yoga. In the world of yoga practice, researchers are interested in the role of intensity and how benefits vary based on intensity levels. Cowen et al., [6], for example, aimed to clarify the physical and mental improvements available with yoga practice, with respect to the varying yogic styles. Cowen et al., randomly assigned seventeen participants into two yoga groups: Ashtanga and Hatha. Ashtanga sessions focused on dynamic standing postures, Hatha sessions focused on relaxed seated postures, and both featured the core elements of yoga philosophy, breathing, and relaxation. Participants met twice weekly, with assessments noted one week before and one week after the study period.

According to the Cowen et al. [6] study, all participants demonstrated progress in strength, endurance, and flexibility. Interestingly, the Ashtanga group showed an even greater degree of progress in these measures. Also, the Ashtanga group alone displayed significant improvements in stress and health perception. It was noted by Cowen and colleagues that some energetic yoga styles, such as Ashtanga, serve not only to maintain but also to increase one’s level of fitness. These findings suggest that certain styles of yoga can yield additional health benefits. More importantly, these apparent health effects provide measurable evidence within a rather diminutive timeframe. Simply stated, unlike other forms of exercise, the benefits of yoga can be enjoyed after a relatively short time commitment.

Benefits of Yoga

It has been established that higher intensity and integrative yoga practices coincide with greater health benefits [2, 6]. As the concept of yoga continues to commercialize, these benefits are becoming more evident to the general population. Yoga is gaining accreditation and popularity as it forges its way into mainstream USA. The ultimate question of yoga is why people practice and what makes one choose (or forgo) this exercise form. Some practitioners, known as yogis (male) or yoginis (female), claim they were drawn to yoga for acclaimed aesthetic reasons, such as health promotion, health maintenance, or weight loss [4]. Others seek the benefits of yoga on a deeper level, desiring personal wellness and the yogic virtues of self-acceptance, mindfulness, and non-competitive spirit [4]. Still others use yoga as a route which allows them to prevent, reduce, or control diseases and their associated risk factors [8]. For those combating chronic illness or rehabilitating an injury, yoga can be seen as an alternative outlet for therapy and healing, as discussed below. However, the most common reason for taking part in a personal yoga practice is to more effectively manage stress [4, 8].

Stress, which contributes to 80% of all diseases and illnesses [1], inhibits an individual’s immune function and quality of life [1, 3]. A review of literature on yoga and stress management in healthy adults was conducted by Chong et al., [1]. Eight studies were reviewed, in which both randomized controlled trial (RCT) and clinical controlled trial (CCT) formats were used. The selection of studies featured Hatha, Kundalini, or Iyengar yogic styles. In all studies, a reduction in stress was noted immediately following yogic intervention. Along with reducing negative affect, yoga was found to enhance cognitive function and one’s perception of health or wellbeing. Participants also discussed improved sleep, optimism, and quality of life. In addition, the yogic practice of diaphragmatic breathing is mentioned as a vital component to stress management. This breathing technique supports increased respiratory efficiency, improves functions of the nervous and endocrine systems, and encourages the fine tuning of the body to maintain a state of homeostasis [9].

Yoga’s function in the alleviation of stress can resultantly ameliorate various factors for chronic disease. Because high blood pressure, high glucose, high cholesterol, and obesity pose the greatest risks for chronic conditions [10], ways of preventing, limiting, or treating these health issues is paramount. Yoga, when used as an integrative health tool, can simultaneously impact all four interrelated factors [10].

Thirty-two experimental, quasi-experimental, or observational articles using both diseased and healthy populations were reviewed by Yang [10]. The results from Yang’s 2007 study indicated that yoga has the ability to positively impact primary risk factors (high blood pressure, high glucose, high cholesterol, and obesity)for chronic disease, thereby improving one’s personal health and longevity. Further, yoga has a direct relationship to weight loss. Yoga practiced at regular intervals allowed participants of one study reviewed by Yang [10] to attain a normal body weight within the first year of intervention. Yang indicated that yoga contributes to a significant decrease in levels of blood glucose, with the earliest results shown after 40 days of practice. Additionally, in patients with hypertension, cardiovascular disease, and diabetes, yoga helped lower blood pressure levels during the third week of trials. Within the fourth week of yogic exercise, Yang further noted measurable decreases in cholesterol with improvements in deterioration. Yogis and yoginis can enjoy the health benefits of yoga early on in their adoption process [10]. This is opposed to the delayed satisfaction oftentimes experienced when engaging in traditional exercise programs.

Yoga as Holistic Therapy

Those who carry the burden of chronic disease can experience relative ease through regular yoga practice. A precise combination of yoga postures, breathing, and meditation is key to unlocking these health benefits, as the healing ability of yoga allows prevention, alleviation, and recovery to occur naturally [11]. Yoga can improve both visible and invisible cues of pain, suffering, and limitations which plague quality of life [11].

Woodyard [12] found that the restorative, rejuvenating, and relaxing nature of yoga has led to its increased usage in treating multiple common disorders. Yoga improves optimism, immunity, and self-acceptance while minimizing fear, anxiety, and irritability [12]. This is essential for individuals who are battling mood disorders. The emotional shift provided by yoga can lead to increased quality and quantity of sleep, thereby improving symptoms of insomnia [8, 12]. Overall, yoga therapy leads to a healthier body image, self-confidence, and mindfulness [12], and, interestingly, Woodyard [12] noted that an increase in these measures reduced the risk of developing addictive behaviors.

Yoga’s comprehensive approach has been shown to have a cumulative effect on internal healing by engaging all muscle groups, internal systems, organs, and glands [12]. In addition, as with many forms of exercise, yoga therapy helps increase blood flow, thereby circulating vital nutrients, oxygen, hemoglobin, and red blood cells to body tissues [12]. Cancer patients in particular have realized the homeopathic effects of yoga therapy and have attributed the relief of nausea, fatigue, pain, and even toxicity to yoga practice, minimizing their need for related prescription medications [12]. Further, yoga has been credited for leading to increased flexibility, improved gait, and increased strength by alleviating pain that would otherwise hinder movement [12].

Yoga practice has also led to pain relief and increased range of motion for individuals with musculoskeletal disorders including osteoarthritis, carpal tunnel syndrome, multiple sclerosis, and chronic back pain [7]. In addition, yoga may hold an important role in improving cardiopulmonary measures including lung function, exercise capacity, and resting heart rate [7]. Yoga practitioners have displayed a reversal of the negative effects of stress, and reduced risk factors for cardiovascular disease and hypertension [7]. Yoga practice has helped individuals maintain and enjoy healthier body weights, lipid levels, and blood pressures [7]. Further, yoga has been shown to reduce the symptoms of obstructive airway diseases by significantly improving oxygen delivery [7].

For certain ailments, yoga has been recognized as an equally effective method of treatment for disease as that of traditional medicine [7]. This evidence of healing, however, is of a holistic platform, one which nurtures the body, mind, and soul to influence three primary realms of wellbeing – physical, emotional, and spiritual. Although not a customary method of treatment, yoga is a trendy physical practice that has yielded attainable health benefits to those of both sound and compromised immunities [8].

Narasimhan et al., [3] examined yoga’s influence on personal affect and found that, after one week of yoga practice, study participants experienced a 47% decrease in overall negative affect and a 13% increase in overall positive affect. The most pronounced emotional differences noted were a 55% decrease in irritability and a 28% increase in feelings of contentment. The seemingly inherent ability of yoga to balance the autonomic nervous system leads to positive emotional shifts for individuals, thus enhancing quality of life.

Monk-Turner and Turner [13] also found that yoga practitioners were more likely to experience increased physical wellness, mental wellness, and spiritual wellness. Yoga practitioners in the Monk-Turner and Turner study displayed healthier levels of fitness, bodyweight, range of motion, and nutrition; demonstrated better ethics, healthier emotions, stronger morals, and an increased ability to express their feelings; and illustrated a healthier approach to faith. Overall, the yoga participants exhibited more positive outlooks on life and demonstrated more genuine happiness. They were more likely than their counterparts to engage in other healthful behaviors and make mindful, responsible choices.

Limitations of Yoga Practice

The all-encompassing nature of yoga has the tendency to draw in widespread appeal. Its positive track record and long-term success in impacting health has provided evidence that yoga is becoming more than just a trend. As the interest in yoga continues to grow, however, a few questions have begun to arise [4]. First, critics question whether the benefits attributed to yoga are real, perceived, or both. In addition, opinions have varied between yoga practitioners and non-practitioners, raising concern about the effects of yoga. And, lastly, some have recognized barriers that prevent individuals from practicing yoga.

A qualitative study was conducted by Atkinson et al., [4] in an attempt to answer these emerging questions and to define and compare the pros, cons, and triggers associated with adopting (or negating) yogic practice while being mindful of experience levels and the impact of experience on decision-making. Atkinson et al., recruited fifty participants and assigned them to groups according to their level of experience with yoga: non-practitioners, beginners (one year or less), and intermediates (more than one year). Perceived benefits, barriers, and other factors of yoga practice were discussed during focus group sessions and revealed that the initiation of yoga therapy is most often prompted by illness onset, disease prevention, injury rehabilitation, word of mouth, and mass media. Participants noted stress reduction as the primary benefit of yoga practice in addition to maintaining personal health, deterring mind/body disease, encouraging social support, and gaining self-acceptance. Time constraints was the primary perceived barrier to engaging in yoga practice, while monetary costs, stigmas associated with practicing yoga, feelings of intimidation, and the potential for adverse health effects, although rare, discouraged yoga practice [4].

Yoga vs. Traditional Forms of Exercise

Despite the increasing popularity of yoga and the wide range of benefits associated with it, some question whether it can compete with traditional forms of exercise. In a recent review article, Ross and Thomas [5] compared the benefits of yoga and the benefits of traditional exercise on the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS) in both healthy and diseased populations. Perhaps not surprisingly, Ross and Thomas found that the benefits of yoga are equal or superior to traditional exercise. They suggest that yoga is a preventive and curative approach for combating chronic diseases, including cardiovascular disease, diabetes, obesity, autoimmune disorders, and mental illnesses. According to Ross and Thomas, yoga practitioners display similar or more desirable levels of blood glucose, cholesterol, inflammation, salivary cortisol, oxidative stress, blood pressure, and heart rate when compared to practitioners of the more traditional forms of exercise. In addition, subjective appraisals of pain, fatigue, stress, mood, anxiety, and sleep were improved with yogic intervention. Both yoga and traditional exercise affect the HPA and SNS continuums; however, yoga instigates a shift in the nervous system response that favors the parasympathetic nervous system while concurrently soothing the SNS.

Discussion

This review of yoga therapy provides evidence to indicate the importance of the connection that exists among the mind, body, and spirit. More importantly, this review has revealed the significance of the mind-body-spirit connection in overall individual health.

The wide range of adaptability that yoga provides encourages widespread appeal. Variations in yoga commitment, including the type, intensity, and duration of yoga therapy, play a role in the level of achievable health benefits, as is the case with all forms of exercise. Benefits and barriers do exist in yoga practice. Stress reduction is the most popular benefit of yoga therapy, and time constraints are the largest barrier. These and other factors should be considered in order to facilitate an increased reliance on yoga as a route toward improved health statuses.

As the understanding of yoga progresses, it is likely that an increased usage of yoga as a form of complementary and/or alternative medicine will emerge in Western culture. Yoga plays a prominent role in stress management and has shown potential in controlling primary risk factors for chronic disease. Yoga can be offered as a supplement to traditional forms of medicine, or it can be integrated as part of a holistic health routine.

Yoga uniquely embraces all realms of human wellness. It is evident that yoga therapy triggers multiple complex reactions in the body, resulting in cumulative effects on the muscles, internal organ systems, and glands and ultimately leading to enhanced quality of life.

Despite mounting evidence declaring yoga’s favorable impact on health, multiple studies to confirm the existing claims are limited. The specific influence of yoga within realms of fitness and health differ in part from varying yogic styles, related intensities, and ensuing benefits. In order to give a more accurate, adequate snapshot of the health effects of yoga, additional and more specific related research is clearly warranted. For reliability purposes, existing studies should be replicated across healthy and diseased populations of varying demographic backgrounds, and, once complete, the results could be compared or meta-analyzed.

Over time and with steadfast research, yoga will continue to be assimilated with other aerobic exercise forms. For this to happen succinctly, more research is needed in order to compare yoga and other popular exercise constituents. Future accomplishments in yoga research would greatly influence the global community to embrace yoga and its health benefits therein.

Conclusions

Yoga is more than just exercise. It can be viewed as a reliable and safe form of complementary and alternative medicine in Western culture today. Yoga has promising potential for healing with documentation to support its ability to ameliorate maladies across the medical spectrum. The evidence presented here clearly suggests the inherent link that exists among one’s body, mind, and spirit. By clarifying this important connection, we can begin to identify the proper use of yoga in holistic health routines for years to come.

Learning Points

• Yoga provides attainable health benefits to those of various statuses of health. Evidence has shown the benefits of yoga in both healthy and diseased populations.
• Yoga provides a range of styles, methods, and intensities to suit individuals with different needs and objectives. Yoga has an adaptive quality matched by few types of exercise.
• Yoga positively contributes to overall quality of life. It has shown potential as a complementary alternative source for health, particularly in prevention and healing.
• Research studies about yoga are scarce, and additional research is needed to increase the understanding of yoga, its limitations and benefits, and its possible uses as a form of alternative therapy.

Authors’ Contribution

TAS: Originator of research idea, literature review, synthesis of information, primary writer.
BSN: Contributor of expertise, editor, secondary writer, corresponding author.

Conflict of Interests

Neither author has a conflict of interest of any type.

Ethical Considerations

Since this was a review of literature and no subjects participated in the study, IRB review/approval was not warranted.

Funding

None

Acknowledgement

None

References

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