The secretion of salivary α-amylase is influenced by adrenergic regulation of the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis; thus, exercise affects the levels of salivary α-amylase. Granger et al published a review in 2007 that focused attention on salivary α-amylase. In addition, a portable system for monitoring salivary α-amylase activity was launched in Japan at the end of 2005. The correlation between exercise and salivary α-amylase has since been extensively investigated. The present review summarizes relevant studies published in the English and Japanese literature after 2006. A search of the PubMed and CiNii databases identified 54 articles, from which 15 original articles were selected. The findings described in these publications indicate that exercise consistently increases mean salivary α-amylase activities and concentrations, particularly at an intensity of >70% VO2max in healthy young individuals. Thus, these studies have confirmed that salivary α-amylase levels markedly increase in response to physical stress. Salivary α-amylase levels may therefore serve as an effective indicator in the non-invasive assessment of physical stress.
Keywords: adrenergic; athlete; physical stress; sympathetic nervous system.