Current Situation of Heat Stress Studies on Kendo Players: A Scoping Review

Background/Objectives: Global warming and the rise in the average temperature in recent years have increased the risk of heat stroke and also deteriorated performance among athletes. Kendo, a traditional Japanese martial art and also a competitive sport, is reported to have high incidents of heat stroke and related mortality. However, there is no heat management guideline for this specific sport to date and research on its heat management practices and risk factors for heat stroke are limited. The present study conducted a scoping review on studies focused on heat stress and the heat management practices of Kendo players. Methods: A literature search was conducted using five databases (PubMed, SCOPUS, Ichu-shi Web, CiNii, and Google Scholar) and also manually from the references of searched articles. Results: Overall, the studies that have investigated the heat stress of Kendo players are scarce and outdated. Of the 15 references that met screening criteria, 11 studies were conducted in a field setting. The vast majority were conducted on male university students and there was a lack of research on females and on different age groups. Common measures of heat management practices used in previous studies were weight changes before and after training (n = 14), body temperature (n = 9), and heart rate (n = 8). Only a few studies used multiple measures to determine heat stress. Conclusions: Considering the continuation of global warming and the increasing risk of heat stroke, further investigation on heat stress, its association with health and performance, and current heat management practices in Kendo players are warranted.