Effects of a Yoga-Based Stress Intervention Program on the Blood Pressure of Young Police Officers: A Randomized Controlled Trial

Systematic Review of Workplace Interventions to Support Young Workers' Safety, Work Environment and Health

PURPOSE

This systematic review investigates the effectiveness of workplace interventions to support young workers' work environment, safety and health.

METHODS

A systematic search was conducted in bibliographic databases including PubMed, Web of Science Core Collection and PsycInfo for English or Scandinavian articles published from 2007 to 2022. The PICO strategy guided the assessment of study relevance and the bibliographical search for randomized controlled trials (RCTs) and non-RCTs in which (1) participants were young workers (mean age: 15-29), (2) interventions were initiated and/or carried out at the workplace, (3) a comparison group was included, and (4) an outcome measure related to work environment, safety and health was reported. We categorized each included study using the intervention classification framework. The quality assessment and evidence synthesis adhered to the guidelines developed by the Institute for Work & Health (Toronto, Canada).

RESULTS

A total of 33 high and medium quality studies showed a moderate level of evidence for no benefit of 'Mental training' on stress. We found limited evidence of a positive effect of the following intervention types: 'Attitude and belief' on mental health problems, 'Behavior based' on anxiety, and 'Multifaceted' on hand eczema. We found limited evidence for no benefit of the following intervention types: 'Mental training' on mental health problems, and 'Physiological modifications' on musculoskeletal disorders. The remaining intervention types showed mixed or insufficient evidence.

CONCLUSIONS

Except for a moderate level of evidence for no benefit of 'Mental training' on stress, the evidence synthesis recommends, that there is not enough evidence from the scientific literature to guide current practices. The results emphasizes a strong need for high quality interventions specifically aiming at increasing or maintaining young workers' work environment, safety and health. Included studies focused mainly on individual measures, highlighting the need for studies investigating possible preventive measures at the group or organizational level.

Effects of circuit training and Yoga on biochemical and psychological responses to stress and cardiovascular markers: A randomized clinical trial with nursing and medical students in Southern Brazil

A Randomized Controlled Trial involving 158 Brazilian medical and nursing students assessed one of three conditions over an 8-week period: 1) a circuit training protocol (CTG); 2) a yoga protocol (YG); or 3) no intervention (CG). The objective was to evaluate the effectiveness of circuit training and yoga protocols in reducing perceived mental stress and examining their effects on serum cortisol levels, as well as on traditional cardiovascular risk factors (CRFs), during an academic semester. Mental stress was measured using self-reported stress questionnaires. For the CTG, comparisons of pre- vs. post-intervention data indicated a reduction in self-reported stress levels on a Brazilian scale (p < 0.001) and an international scale (p < 0.05). Regarding CRFs, there was a reduction in waist circumference (WC) (p < 0.05), systolic blood pressure (SBP) (p < 0.05), and heart rate (HR) (p < 0.001). No changes were observed in diastolic blood pressure (DBP) (p = 0.211) and serum cortisol (SC) (p = 0.423). In the YG, pre- vs. post-intervention data indicated a reduction in self-reported stress levels on the ISSL (p < 0.001), in both resistance and exhaustion stress levels on the PSS scale (p < 0.001), and in SC levels (p < 0.001), WC (p < 0.05), and SBP (p < 0.05); however, HR and DBP did not change (p = 0.168 and p = 0.07, respectively) in this group. No changes were noted in any measures in the CG. The intervention protocols demonstrated that both CTG and YG can positively impact mental or biochemical stress responses, as well as CRFs.

The BERN Framework of Mind-Body Medicine: Integrating Self-Care, Health Promotion, Resilience, and Applied Neuroscience

Background: Mind-body medicine (MBM) focuses on improving our understanding of how the interactions between the brain, mind, body, and behavior can be used to promote health. In this narrative review, we present the basic principles of MBM, including the introduction of a rational framework for the implementation of MBM-based interventions. We also discuss the contributions of MBM to motivation and reward systems in the brain including those that may specifically involve the mitochondria.

Results: MBM can be used to promote health in patients with chronic diseases, especially conditions identified as lifestyle-related. MBM builds on salutogenesis, which is a paradigm that focuses on health (as opposed to disease) determinants and the development of individual resilience and coherence factors as a means to reduce stress, decrease the burden of disease, and improve the quality of life. This approach involves several well-known principles of self-healing and self-care. MBM interventions typically include behavioral modification techniques in conjunction with cognitive work focused on stress regulation, exercise, relaxation, meditation, and nutrition. We suggest the use of the acronym “BERN” (Behavior, Exercise, Relaxation, and Nutrition) to summarize the operational framework of this approach.

Discussion: Different BERN techniques act via shared autoregulatory central nervous system (CNS) reward and motivation circuitries. These systems rely on numerous neurobiological signaling pathways with overlapping effector molecules that converge, e.g., on nitric oxide (NO) as a common effector molecule. NO is critically coupled to reward physiology, stress reduction, and self-regulation as it modulates the responses of various mitochondrial, nuclear, and chromosomal processes within brain cells. NO has also been implicated in relevant outcomes (e.g., the placebo response).

Conclusions: MBM interventions typically follow the BERN model and aim to strengthen health and resilience, and reduce stress. The mechanisms of action of these processes involve the CNS reward systems and correlate with placebo and self-healing pathways.