Background: Exposure to a warm environment has been reported to be effective for recovery from mental fatigue. However, there have been no reports examining the effects of a pellet stove on recovery from mental fatigue. The purpose of this study was to examine the effects of a pellet stove on recovery from mental fatigue.
Material/Methods: In this placebo-controlled, crossover experiment, 16 healthy volunteers were randomized into the pellet stove and control groups. After a 30-min fatigue-inducing mental task session, participants moved to a recovery room with (pellet stove condition) or without (control condition) a pellet stove to see the image of a pellet stove for 30 min.
Results: After the recovery session, the participants exposed to the pellet stove condition showed lower total error counts of a cognitive test, higher levels of subjective healing, comfort, and warmth, and sympathetic nerve activity and higher parasympathetic nerve activity as compared with the control condition.
Conclusions: These results provide evidence that improved cognitive function, subjective mental states, and balance of the autonomic nervous activities result from using a pellet stove during the recovery session. Hence, the pellet stove was effective for the recovery from mental fatigue.

Keywords: Reference Values, Placebos, Mental Fatigue