O-369 the Effects of Constant Ambient Temperature on Alertness: Potential Benefits of Dynamic Conditions in Offices

Introduction Studies support the association of core body temperature with the circadian rhythm and cognitive performance aspects, including alertness. Additionally, evidence shows that lower ambient temperatures improve cognitive performance. However, less is known on the dynamic effect of ambient temperature on alertness, which could also follow the circadian rhythm. This study aimed to investigate changes in alertness throughout the day under two different thermal conditions. Methods Participants (NTotal=31, NFemale=16, NMale=15, Average age: 40.7 years) attended a two-day hybrid (laboratory and field) study, which included a cross-over design exposure to two different thermal conditions (cool condition: 21 °C, warm condition: 28 °C) for 8 hours in a simulated office environment. They were asked to answer questions on how alert they were feeling at regular intervals throughout the day, also in their home environment. Ambient temperature was monitored continuously with the use of a non-commercial, tailor-made sensor. Results The results indicate an interaction effect of condition-by-time on the levels of reported alertness (F(15, 21)=6.245, p =.01). Participants reported being more alert in the morning, when they were exposed to the warm condition, compared to the cool condition. However, a sudden reduction in alertness level was observed in the afternoon when they were exposed to the warm condition, compared to the cool condition, in which participants showed increases in alertness. Discussion These outcomes suggest that constant temperatures in offices might not be ideal for enhanced alertness. Conclusion It is suggested that offices might benefit from dynamic temperature exposures that go against the circadian rhythm of body temperature.