Objective: This study analyzed the efficacy of aromatherapy in improving work performance and reducing workplace stress.
Subjects: The initial sample comprised 42 administrative university workers (Mage = 42.21 years, standard deviation = 7.12; 10 male).
Intervention: All sessions were performed in a university computer classroom. The participants were randomly assigned into an aromatherapy group (AG) and a control group (CG), and they were invited to participate in a specific session only once. They were seated in front of a computer. During the intervention period, some oil diffusers were switched on and were in operation throughout the session with petitgrain essential oil for AG sessions and a neutral oil (almond) for CG sessions. At the same time, participants completed a computer task on a specific Web site typing on their keyboard until they had finished it. The single times were different for all participants and were recorded on the Web site as "performance time."
Outcome measures: Before and after the intervention, participants completed anxiety and mood state questionnaires (the Stait-Trait Anxiety Inventory [STAI] and the Profile of Mood States [POMS]). Heart-rate variability (HRV) was measured before (PRE), during (20-25 min), and after (POS) the intervention to analyze autonomic nervous system regulation.
Results: The AG performed the Web site task 2.28 min faster than the CG (p = 0.05). The two groups showed differences in the following HRV parameters: low frequency (p = 0.05), high frequency (p = 0.02), standard deviation of all RR intervals (p = 0.05), and root mean square of differences (p = 0.02). All participants in all groups showed a decrease from PRE to POST for STAI (p < 0.001), Tension-POMS (p < 0.001), and Vigour-POMS (p = 0.01) scales.
Conclusions: Aromatherapy (inhaling petitgrain essential oil) can improve performance in the workplace. These results could be explained by an autonomic balance on the sympathetic/parasympathetic system through a combined action of the petitgrain main components (linalyl acetate, linalool, and myrcene). The final effect could be an improvement of the mental and emotional condition by a combination of reducing the stress level and increasing the arousal level of the participants in terms of attentiveness and alertness.
Keywords: aromatherapy; autonomic balance; burnout; heart rate variability; work performance; workplace stress.