This guest editorial from the Thermal and Mountain Medicine Division of the U.S. Army Research Institute of Environmental Medicine provides recent evidence about individualized factors that may influence heat-related illness risk and strategies to prepare for training in heat.

Since 2001, MSMR has published regular updates on the incidence of heat illness among U.S. active component service members. This update presents summaries of heat stroke and heat exhaustion case counts, incidence rates, and locations between 2020 and 2024.

This annual update provides more recent data on the incidence of exertional hyponatremia, a condition in which water and electrolytes lost during or after heavy exertion are replaced only by water, which can lead to death or serious morbidity if left untreated.

This annual update provides more recent data on the incidence of exertional rhabdomyolysis, a pathologic muscle breakdown associated with strenuous physical activity.

This report summarizes heat stroke and heat exhaustion case counts, incidence rates, and locations among U.S. active component service members from 2019 through 2023.

This report summarizes Military Heath System (MHS) data from 2019 through 2023 on the numbers, frequency, rates, trends, demographics, geographic locations, as well as military characteristics of exertional rhabdomyolysis among U.S. active component service members.

This report summarizes Military Heath System data from 2008 through 2023 on the numbers, frequency, rates, trends, demographics, geographic locations, as well as military characteristics of exertional hyponatremia among U.S. active component service members.

The World Meteorological Organization, which monitors climate, weather, and water resources for the United Nations, has declared that 2023 was the hottest year in recorded history.

View articles from past issues of MSMR.