We are determining the influence of dehydration and rapid rehydration on brain function.

Workers repeatedly endure physically demanding tasks for prolonged periods of time on a daily basis, resulting in consecutive days of substantial physical fatigue. These repeated workdays can lead to short-term health consequences such as increased risk of musculoskeletal injury and long-term concerns such as kidney injury. To prevent these health concerns, we are determining the body temperature, fatigue, and hydration responses to repeated workdays in a hot environment. 

Predicting how much energy Warfighters use and when they will become exhausted has been completed almost exclusively for males. Differences in physical performance capabilities, body composition, how the body regulates temperature during work, and metabolism may cause different responses in females Warfighters, who are serving in combat roles in greater numbers than before. Sex differences in the energy needs of Warfighter tasks are additional problems that must be addressed. Therefore, the purpose of this study is to determine energy needs during fatiguing Warfighter tasks in a variety of environments. 

Measuring muscle fatigue during work is of great importance to regulate work demands while maintaining work productivity. Accelerometers can be used to quantify fatigue, with certain calculated variables indicating greater fatigue. This study sought to validate the use of accelerometers to quantify fatigue across walking speeds, inclines, and while walking with a backpack.

Military members often carry heavy loads while marching to complete missions. This marching can increase risk of injuries of the legs such as sprains and strains. Most previous studies investigating the impact of carrying heavy loads in male participants. With the opening of combat positions to women, there is an increased need to determine injury risk following walking with heavy loads in females. This study is determining musculoskeletal injury risk following load carriage in female Warfighters.

Recommendations for work in the heat suggest working to work-to-rest ratios depending on the work intensity and the extreme environment. These recommendations aim to prevent excessive core body temperature rise and dehydration but their usefulness to achieve these aims is unknown. Even less is known about the body’s responses to work in the heat among variations of work/rest cycles. Therefore, the purpose of this study is to determine whether these worker recommendations prevent excessive core body temperature rise and dehydration. 

Worker recommendations for hydrating during work in the heat are limited and generalized to all workers. Despite individual hydration needs depending on a variety of factors including the work intensity, specific environment conditions, or individual needs, all workers are suggested to drink the same amount in a similar fashion. This study challenged this idea by comparing two drinking strategies for work in the heat.

Consecutive workdays in the heat leads to worsened responses on the second day of work compared to the first. This may be due to inadequate recovery following work. This study sought to compare recovery measures following prolonged work in the heat.

A variety of recommendations to modify or cancel physical activity in the heat rely on a calculation of the environment, termed wet bulb globe temperature (WBGT). Both a hot/dry environment and a warm/humid environment will create a similar WBGT using this calculation despite a potential difference in how the body responds in these two very different types of environments. This study sought to determine the way the body responds to different hot environments of an equal WBGT.

Heat emergencies can occur in remote areas where cold water immersion is not possible. Wildland firefighters carry water for hydration purposes and materials that could be used as a tarp. This study compared body cooling rates using tarp-assisted cooling with materials available in the wilderness with the current standard care of dousing someone in water and hiking them out to advanced medical personnel.  

Cold water immersion is the best treatment option for exertional heat stroke patients. This study sought to optimize the cold water immersion cooling strategy to create a fast core body temperature cooling rate and compare core body temperature responses following immersion.