| Title | Heart rate variability at different thermal comfort levels. | ||
| Author | Liu, Weiwei; Lian, Zhiwei; Liu, Yuanmou | ||
| Journal | Eur J Appl Physiol | Publication Year/Month | 2008-Jun |
| PMID | 18351379 | PMCID | -N/A- |
| Affiliation | 1.Institution of Refrigeration and Cryogenics, Shanghai Jiao Tong University, 800 Road Dongchuan, 200240 Shanghai, China. lww_809@tom.com. | ||
The mechanism of human thermal comfort is important for building a comfortable and healthy indoor environment. This paper analyzes human heart rate variability (HRV) at different thermal comfort levels and discusses the mechanism of human thermal comfort. A total of 33 subjects were divided in 3 groups. Under air temperatures of 21, 24, 26, 28, 29, and 30 degrees C, the subjects\' electrocardiogram was recorded for 5 min. HRV (the ratio of absolute powers in low- and high-frequency bands, LF/HF ratio) was analyzed. LF/HF at discomfort level were significantly higher than that at comfort level (P < 0.05), despite the same thermal sensation. The results indicate that sympathetic activity plays an important role in subjects\' thermal discomfort and the LF/HF ratio may be used as an indicator for human thermal comfort.