Inhaled peppermint, rosemary and eucalyptus essential oils do not change spirometry in healthy individuals

A multichannel investigation of proprioceptive accuracy

Proprioceptive accuracy (PAc), i.e., the acuity of perception of the state of different parts of the motor system, shows substantial intraindividual differences, and is often considered a general ability. However, it is questionable whether there is an association between accuracies measured with different tests at different body sites. PAc with respect to both knee and elbow joints (joint position reproduction) and the flexors of the upper arms (weight discrimination) was measured in 87 young healthy individuals with regular physical activity across multiple indices. Expected and perceived performance was also assessed for each behavioral task. Frequentist and Bayesian analysis largely supported the idea that PAc with respect to various parts of the motor system are unrelated. No dominant-subdominant differences for actual performance were found; however, PAc for the dominant and subdominant limb were associated in many cases. Finally, perceived performance was related to expected but not to actual performance for all three proprioceptive modalities. In conclusion, actual accuracy of perception of the actual state of a part (i.e., joint, muscle) of the motor system cannot be generalized to other parts. Perceived accuracy, dominantly shaped by expectations, is independent from actual accuracy.

Heart rate perception and expectation impact laboratory-induced perceived stress

Previous studies have shown that the human capacity to gauge one's own physiological state is notoriously flawed. The cause for the mismatch between perceived and physiological stress has not yet been properly identified. In this study, we assumed that cardioceptive accuracy (CAc) is positively associated with cardiovascular reactivity, and CAc and expectation about stress might account for the discrepancy between perceived and physiological stress. In a crossover experiment, we assessed cardioceptive accuracy in two ways (mental heartbeat tracking task and perception of heart rate), and induced physiological (handgrip exercise) and mental (N-back task) stress in 64 university students (51 % male, mean age 22.2). We assessed cardiac and electrodermal activity, and expected and perceived stress. We found that indicators of cardioceptive accuracy were not associated with cardiovascular reactivity. However, heart rate perception moderated the association between the change in heart rate and perceived stress in the physical but not in the mental task. Whereas heartbeat tracking accuracy was not associated with perceived stress. Moreover, perceived stress was predicted by the expected stress but not by the change in heart rate and electrodermal activity in the mental stress task. In conclusion, heart rate perception and expectation of stress may shape perceived stress more than actual physiological changes in moderate acute stress.

Vague sensations. About the background and consequences of discordance between actual and perceived physiological changes

Empirical evidence consistently shows that discordance, also called dissociation or discrepancy, between actual physiological (mainly visceral) events and their perceived counterparts is substantial. On the one hand, we typically do not perceive actual visceral events occurring in our bodies; on the other hand, sometimes we do perceive bodily changes that do not really take place. This narrative review presents the available empirical findings on the discordance, and summarizes possible explanations that approach the phenomenon from the viewpoint of evolution, cognitive development, and predictive processing. Also, the role of top-down factors, such as expectations and experiences is discussed. Finally, practically relevant consequences of the discordance are presented using the examples of mind-body practices, the placebo and nocebo phenomenon, and medically unexplained symptoms. It is concluded that the discordance between actual and perceived body changes can have a negative impact on health, mainly through issues with adherence and other behavioral factors. The existence of actual-perceived discordance should be taught and demonstrated in the elementary and high school, as well as in many areas of higher education.

Inhalation of Spray-Dried Extract of Salvia rosmarinus Spenn Alleviates Lung Inflammatory, Oxidative, and Remodeling Changes in Asthmatic Rats

INTRODUCTION

For centuries, Salvia rosmarinus Spenn has been applied as folk medicine to cure different diseases due to its anti-inflammatory, antibacterial, antioxidant, antifungal, and antitumor effects. To find bioactive medicinal herbs exerting a protective effect on airway inflammation and remodeling, we assessed the anti-oxidative and anti-inflammatory effects of an aqueous spray-dried extract of Salvia rosmarinus Spenn. (rosemary) in an ovalbumin-induced asthmatic rat model.

METHODS

Rats were randomly divided into normal control (control), asthma, asthma+rosemary extract (RE) (13 mg/kg), asthma+RE (50 mg/kg), and asthma+budesonide groups. After 50 days, animals were anesthetized, and then blood, bronchoalveolar lavage fluid (BALF), and lung tissues were collected for subsequent serological and pathological studies. Histopathology of lung tissues was evaluated by H&E staining. The oxidative stress parameters and airway inflammation factors in BALF and lung tissue were explored.

RESULTS

Using thin layer chromatography, the presence of rosmarinic acid was confirmed in aqueous extract of rosemary. Furthermore, RE markedly decreased immunoglobulin E levels (50 mg/kg; p < 0.001 vs. asthma group) and inflammatory cytokines (50 mg/kg; p < 0.001 vs. asthma group) and increased antioxidant enzymes (50 mg/kg, p < 0.001 vs. asthma group). Furthermore, RE at a concentration of 50 mg/kg obviously reduced the number of inflammatory cells, goblet cells, and pathological changes compared to the asthma group.

CONCLUSION

The results showed that RE administration might prevent or alleviate allergic asthma-related pathological change, probably via antioxidant and anti-inflammatory mechanisms.

Distinguishing science from pseudoscience in commercial respiratory interventions: an evidence-based guide for health and exercise professionals

Respiratory function has become a global health priority. Not only is chronic respiratory disease a leading cause of worldwide morbidity and mortality, but the COVID-19 pandemic has heightened attention on respiratory health and the means of enhancing it. Subsequently, and inevitably, the respiratory system has become a target of the multi-trillion-dollar health and wellness industry. Numerous commercial, respiratory-related interventions are now coupled to therapeutic and/or ergogenic claims that vary in their plausibility: from the reasonable to the absurd. Moreover, legitimate and illegitimate claims are often conflated in a wellness space that lacks regulation. The abundance of interventions, the range of potential therapeutic targets in the respiratory system, and the wealth of research that varies in quality, all confound the ability for health and exercise professionals to make informed risk-to-benefit assessments with their patients and clients. This review focuses on numerous commercial interventions that purport to improve respiratory health, including nasal dilators, nasal breathing, and systematized breathing interventions (such as pursed-lips breathing), respiratory muscle training, canned oxygen, nutritional supplements, and inhaled L-menthol. For each intervention we describe the premise, examine the plausibility, and systematically contrast commercial claims against the published literature. The overarching aim is to assist health and exercise professionals to distinguish science from pseudoscience and make pragmatic and safe risk-to-benefit decisions.

Repeated Inhalation of Peppermint Essential Oil Improves Exercise Performance in Endurance-Trained Rats

Peppermint essential oil, being natural and safe, with antioxidant and anti-inflammatory properties, has long been a research interest in relieving fatigue and improving exercise performance. However, the related studies report controversial results, and the mechanisms remain unclear. Here we found that inhalation of peppermint essential oil significantly extended the exhaustion time in rats subjected to 2-week weight-bearing swimming training. Sprague-Dawley rats were subjected to a 2-week weight-loaded forced swimming regimen. Prior to each swimming session, the rats were administered peppermint essential oil via inhalation. An exhaustive swimming test was performed at the end of the protocol. Rats treated with essential oil had significantly extended time to exhaustion compared with exercised rats without essential oil treatment. In addition, treated rats also showed reduced oxidative damage induced by endurance exercise. Notably, the rats receiving two-week essential oil inhalation while not subjected to swimming training did not show improved exercise performance. The findings demonstrate that repeated inhalation of peppermint essential oil enhances the effects of endurance training and improves exercise performance partially by preventing oxidative damage.

Are there placebo or nocebo effects in balancing performance?

Placebo and nocebo effects could influence the perceived, actual, or both postural stabilities. Therefore, this experiment examined whether postural stability is susceptible to placebo and nocebo effects. Driven by expectations, these cognitions could influence the motor stability of people in physical rehabilitation and those with motion instability. We randomly assigned 78 participants to a placebo, nocebo, or control group. Then, we applied a sham sports cream with positive, negative, or neutral instructions about its impact on balance. Next, we tested postural stability with a modified version of the Modified Clinical Test of Sensory Interaction in Balance, including standard, proprioceptive, visual, and vestibular tests before and after the intervention. Further, we measured expected and perceived performance with visual analog scales and assessed trait anxiety, change in state anxiety, optimism, holistic thinking, persistence, and cooperation with questionnaires. The intervention did not affect actual test performances; similarly, trait and state variables and expectations did not have an impact. Furthermore, the experimental manipulation and trait and state variables did not significantly affect perceived performance. However, the association between expectation and perceived performance was strong (ϱ = 0.627, p < 0.001). These findings suggest that postural stability is not susceptible to placebo and nocebo influences. Still, there is a dissociation between objective and subjective performance, showing that expectations impact perceived but not actual performance, which could fuel motivation in rehabilitation settings.

Expectation predicts performance in the mental heartbeat tracking task

The mental heartbeat tracking task by Schandry is sensitive to non-interoceptive (top-down) influences, e.g., estimation of heart rate and expectation. The two studies reported here investigated the impact of these factors on the outcome of the task. In Study 1, performance-related expectation was assessed between the training interval and the real trials. Performance was strongly related (β = .595, p < .001) to expectation even after controlling for sex, body fat, resting heart rate and estimation of heart rate. In Study 2, expectation was assessed before and after the training interval for Group 1 and 2, respectively. The strong association (r = 0.78, p < .001) between performance and expectation was replicated for Group 2; however, a moderate association (r = 0.39, p < .01) was also found in Group 1. People with high expectation may be prone to categorize and count vague sensations, such as attention evoked sensations, as heartbeats; this can lead to an inflated Schandry-score.

Integrative medicine considerations for convalescence from mild-to-moderate COVID-19 disease

The majority of individuals infected with SARS-CoV-2 have mild-to-moderate COVID-19 disease. Convalescence from mild-to-moderate (MtoM) COVID-19 disease may be supported by integrative medicine strategies. Integrative Medicine (IM) is defined as healing-oriented medicine that takes account of the whole person, including all aspects of lifestyle. Integrative medicine strategies that may support recovery from MtoM COVID-19 are proposed given their clinically studied effects in related conditions. Adoption of an anti-inflammatory diet, supplementation with vitamin D, glutathione, melatonin, Cordyceps, Astragalus and garlic have potential utility. Osteopathic manipulation, Qigong, breathing exercises and aerobic exercise may support pulmonary recovery. Stress reduction, environmental optimization, creative expression and aromatherapy can provide healing support and minimize enduring trauma. These modalities would benefit from clinical trials in people recovering from COVID-19 infection.