Related Experiment Video
Updated: Jan 9, 2026
08:22
Using an Ingestible Telemetric Temperature Pill to Assess Gastrointestinal Temperature During Exercise
Published on: October 7, 2015
11.0K
Can evaporative cooling attenuate physiological and perceptual responses during exercise in Hot/Dry and Warm/Humid
Ken Tokizawa1, Hidenori Otani2
1National Institute of Occupational Safety and Health, Japan.
Industrial Health
|November 30, 2025
Summary
Evaporative cooling with a water-soaked shirt and ventilation garment significantly reduced core body temperature and sweat loss during exercise in hot and humid conditions. This cooling method also improved thermal comfort and reduced perceived exertion.
Area of Science:
- Environmental Physiology
- Thermoregulation
- Human Performance
Background:
- Heat stress during exercise poses risks to physiological function and performance.
- Effective cooling strategies are crucial for individuals exercising in hot environments.
Purpose of the Study:
- To evaluate the efficacy of evaporative cooling using a water-soaked inner t-shirt with a ventilation garment.
- To assess its impact on physiological and perceptual responses during walking exercise in Hot/Dry and Warm/Humid conditions.
Main Methods:
- Eight men walked for 60 minutes in controlled (CON) and evaporative cooling (EVA) conditions.
- EVA involved a water-soaked inner t-shirt and a ventilated jacket (fan-on).
- Physiological (rectal temperature, sweat loss) and perceptual (thermal sensation, discomfort) data were collected.
Main Results:
- Evaporative cooling (EVA) significantly lowered rectal temperature by ~0.4 °C compared to control (CON) in both environments (p<0.002).
- Whole-body sweat loss was halved in EVA compared to CON in both Hot/Dry and Warm/Humid conditions (p<0.001).
- Thermal sensation and discomfort were significantly reduced with EVA (p<0.05).
Conclusions:
- Wearing a water-soaked inner t-shirt with a ventilation garment effectively mitigates thermophysiological strain and perceptual discomfort.
- This cooling strategy is beneficial in environments exceeding skin temperature and in high humidity conditions (WBGT ≤ 31.5 °C).
Related Concept Videos
01:26Requirements for Human Life
12.4K
The Earth and its atmosphere have provided humans with air, water, and food, but these are not the only requirements for survival. Humans also require a specific range of temperature and pressure that the Earth and its atmosphere provides.
Oxygen
Atmospheric air is only about 20 percent oxygen, but that oxygen is a key component of the chemical reactions that keep the body alive, including the reactions that produce ATP. Brain cells are susceptible to a lack of oxygen because they require a...
Oxygen
Atmospheric air is only about 20 percent oxygen, but that oxygen is a key component of the chemical reactions that keep the body alive, including the reactions that produce ATP. Brain cells are susceptible to a lack of oxygen because they require a...
12.4K
02:45Responses to Heat and Cold Stress
14.6K
Every organism has an optimum temperature range within which healthy growth and physiological functioning can occur. At the ends of this range, there will be a minimum and maximum temperature that interrupt biological processes.
14.6K
01:26Thermoregulation
2.2K
The human body has a sophisticated thermoregulation system that employs negative feedback mechanisms to maintain an optimal core temperature. When the core temperature drops, peripheral and central thermoreceptors send signals to the hypothalamus, activating the heat-promoting center. This center triggers several responses aimed at increasing the core temperature. First, vasoconstriction reduces the flow of warm blood from internal organs to the skin so that the heat is not lost from the skin,...
2.2K
01:19Mechanism of heat transfer
1.8K
Understanding heat transfer mechanisms is essential for understanding how our bodies maintain balance in different environmental conditions. When the environment is thermoneutral, the body is in a state of balance, neither using nor releasing energy to maintain its core temperature. However, when the environment is not thermoneutral, the body employs four heat transfer mechanisms to maintain homeostasis: conduction, convection, evaporation, and radiation. These mechanisms facilitate heat...
1.8K
01:14Mechanisms of Heat Transfer
1.6K
Heat transfer between the human body and its environment occurs through four main mechanisms: conduction, convection, radiation, and evaporation.
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant...
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant...
1.6K
01:25Body Temperature
4.0K
The body's temperature, measured in degrees, is determined by the balance between heat production and dissipation to the surrounding environment. For instance, if exercising vigorously, the body will produce more heat, causing sweat and dissipating that heat. Despite extreme environmental conditions and physical exertion, the human temperature-control system maintains a constant core body temperature (the temperature of deep tissues, which are the tissues located beneath the skin and other...
4.0K