Yoga is an ancient Indian philosophy and spiritual practice that has gained popularity in the West as a system of mental and physical health promotion [1]. Modern yoga practice includes physical postures, breathing techniques, relaxation, and meditation [1,2]. A survey among yoga practitioners in the UK indicated that many practitioners engaged with yoga due to perceived or experienced health benefits [2]. As a cost-effective health-supportive practice, yoga is slowly being integrated into mainstream healthcare systems [3]. However, some believe yoga is under-utilised in healthcare, considering its potential benefits [4]. Most practitioners believe that yoga improves physical and mental health, and many use it to help manage medical conditions [2]. The burgeoning research on the use of yoga for health is also encouraging [5,6]. To promote further use of yoga in healthcare, HCPs are key. Currently, however, there is a knowledge gap about their receptivity and engagement with yoga for health, which this research aims to address.

A recent bibliometric analysis of systematic reviews assessing the evidence relating to yoga for health indicated a sharp rise in publications over the past decade [5]. This reflects an increased interest in using yoga to prevent and treat medical conditions, with studies showing mostly promising results [6]. Many yoga studies were of low quality [5], however, and could only endorse the potential of yoga to support various conditions. Evidence is stronger for the use of yoga to support the treatment of depression [[7], [8], [9]], stress [10], anxiety [11], low back pain [12], chronic nonspecific neck pain [13], headaches [14], type 2 diabetes [15,16], and for managing symptoms and quality of life for women with breast cancer [17]. Evidence also suggests benefits for women's health, including during pregnancy [18] and menopause [19]. Yoga is recommended by the American College of Rheumatology for the management of osteoarthritis [20] and by the American College of Physicians [21] and the National Institute for Health and Care Excellence [22] as a non-invasive treatment for low back pain. Additionally, yoga has been found to support health-promoting behaviours, such as reduced BMI among those who are overweight or obese [23], smoking cessation [24], healthier eating behaviour and increased physical activity [25], and improved sleep patterns [26].

Various explanations have been proposed as to the potential mechanisms underlying yoga's effectiveness [27]. Most explanations include a shift from the sympathetic nervous system, typically associated with the ‘fight or fight’, stress response, to the parasympathetic branch, typically associated with physiological ‘rest and digest’ activity [27]. Gard et al. [28] theorised that yoga enhances physical and mental health through self-regulatory mechanisms elicited by sustained physical postures, breath regulation, meditation, and ethical principles. They proposed that practising these elements of yoga may improve cognitive, emotional, behavioural, and autonomic outputs through the integration of top-down and bottom-up regulation. Top-down regulation includes high-level cognitive processes such as meta-awareness, attention, intention, and inhibition; the focus of mindfulness and cognitive-based therapies [28]. Bottom-down processes, promoted through breathing and movement practices, have been found to directly influence physiological processes and structures, including increased vagal tone, baroreceptor stimulation, diaphragm strengthening, and enhanced low-level brain networks [28].

While the research and practice of yoga have been progressing and expanding, the integration of yoga into healthcare has been slower. Gupta et al. [29] reported a 7.8% increase in yoga research publications globally between 2007 and 2016. A national survey in the US indicated that the lifetime prevalence of yoga use increased from 9.7% to 13.5% between 2007 and 2012 [30]. However, this study also found a very small proportion (0.2%) practised yoga due to HCPs' recommendation and this proportion declined across the five years. While dated, a nationally representative study of yoga prevalence in England also indicated an increasing trend in recent yoga practice between 1997 and 2008 [31]. A separate nationally representative study in England indicated that only 3% of patients referred by a GP to complementary and alternative medicine (CAM) therapy were referred to yoga compared to 8% of those who self-referred, suggesting under-referral of yoga by GPs [32]. This same study indicated that yoga was underfunded by the UK's National Health Service (NHS) with only 3% of those who benefited from a funded CAM treatment receiving yoga, compared with 9% of those who had to pay themselves. Over the past few years, a movement to integrate yoga into healthcare has been gaining traction [33]. The NHS has acknowledged the need to reduce the burden of disease through effective prevention and has pledged support for integrated care by collaborating with organisations that support health, such as those providing yoga [34].

Referral, specifically through social prescribing, is the main route through which yoga is being integrated into the UK's NHS [3]. Social prescribing promotes the use of voluntary or community services through recommendations from primary care settings [35]. A qualitative evaluation of a yoga program developed for social prescribing within the NHS, Yoga4Health, found the program to be acceptable, even for high-risk patient groups [36]. Participants reported improved physical and mental health, social connection, health self-management, and positive lifestyle changes. Primary-care referral, for example through GPs, has been found to be a foundational step in initiating the social prescribing process [37]. Understanding perceptions of yoga among HCPs will help identify barriers to further incorporating yoga into healthcare. While there have been no studies in the UK investigating this, a study in the US has explored perceptions of yoga among students enrolled in healthcare programs [4]. This study found that while healthcare students were open to referring patients to yoga, their perceptions of the appropriateness of yoga for medical conditions underestimated the potential of yoga when considering the supporting evidence. A study investigating CAM recommendations and professional use among nurses in Australia suggested low levels, especially for yoga, despite relatively higher personal use and positive attitudes [38]. In contrast, research in the US among rehabilitation professionals indicated that yoga was one of the most used integrative health practices for self-care and patients [39].

The use of theories to understand behaviour is increasingly recognised as important, especially for the development of behaviour change interventions in the complex field of public health [40]. The COM-B model [41] covers a comprehensive range of behavioural influences and is applicable across a wide variety of contexts, including among HCPs [42]. The model recognises that behaviour is generated through the interaction of capability, opportunity, and motivation. Capability refers to an individual's physical and psychological competence to engage in the target behaviour, including knowledge and skills. Opportunity refers to factors external to the individual which facilitate or inhibit the behaviour. Motivation covers a range of mental processes that energise behaviour, including goals, decision-making, habits, and emotions. The COM-B model was used to qualitatively explore barriers and enablers to social prescribing for mental health among GPs [43]. Using this framework, they found that GPs acknowledged the utility of social prescribing to address patients' unmet needs in a de-medicalised way. GPs were enabled by the ability to build trusting relationships with patients and motivated by their positive feedback. The study identified the need for more formal training, a more structured process, and greater workplace support to promote social prescribing. Other studies that have used the COM-B model to understand HCPs' behaviours include referrals to community-based physical activity [44], providing lifestyle-based support for young mothers [45], and delivery of a children's health assessment [46].

Results from a study exploring the integration of CAM, including yoga, into NHS sites across the UK provide a further understanding of barriers and facilitators to using or referring yoga in medical settings [47]. Frequently cited facilitators of effective integration included staff enthusiasm, service setting, patient support, mutual benefit between services, positive results, low/no cost, and high-quality practitioner training, and regulation. While prevalent barriers included issues of funding and costs, negative perceptions of CAM among clinicians, opposition from NHS staff, lack of space, lack of access to patient records, and lack of evidence. Similarly, research in the US found a lack of training, payment issues, and a lack of research funding to be key barriers to the use of CAMs, including yoga, by rehabilitation professionals [39]. Qualitative research among GPs exploring the integration of CAMs into care for comorbid musculoskeletal and mental health conditions indicated that in addition to structural barriers, lack of knowledge about CAMs and philosophical differences between health and healthcare were evident [48]. While this provides some understanding of HCPs' attitudes towards CAM, yoga is perceived by some HCPs as different from CAM [48]. Research among oncologists found them to view yoga as more aligned with physical activity rather than CAM [49]. A recent survey of Australian mental health practitioners’ attitudes to yoga indicated the need for evidence-based guidelines, training, and workplace resources to support integrating yoga practices into clinical settings [50].

To our knowledge, no study has comprehensively assessed perceptions of and experiences with yoga among a range of HCPs. This study aims to address this gap by assessing HCPs’ perceptions of yoga for health and their willingness to recommend yoga to patients, including barriers and facilitators to doing so, using the COM-B framework. Based on the research reviewed, it is hypothesised that HCPs will be open to recommending yoga but may experience barriers related to capacity and opportunity. Major barriers are theorised to include a lack of sufficient knowledge about yoga for health and workplace restrictions relating to support, funding, and resource pressures. Medical doctors are expected to be more sceptical due to greater adherence to evidence-based guidelines.