Clinical trial NCT04241900: Effect of Aging and Aerobic Fitness Level on Heat Dissipation
Official title: Effect of Aging and Aerobic Fitness Level on Heat Dissipation in Neutral Conditions
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Risk of Heat Stress
Keywords: heat loss
aging
aerobic fitness level
heat stress
Lead sponsor: University of Thessaly
Sponsor class: OTHER
First posted: 2020-01-27
Enrollment: 431
Sex: ALL
Minimum age (years): 9
Maximum age (years): 60
Standard ages: CHILD
ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: PREVENTION

Brief summary: In the context of global aging, the health risk factors associated with exercising or working in the heat for aging population are exacerbated by the rising in global surface temperatures. The purpose of this investigation is to determine at what age the heat loss decrements occur and to examine if aerobic fitness level can affect the heat loss capacity in neutral environmental conditions.

Detailed description: All trials were conducted to indoor gyms with the same environmental temperature and relative humidity, 26 - 30oC and 40-50% respectively, to ensure no difference in body temperature were due to the external thermal stress. The participants were instructed to refrain from intense exercise as well as alcohol and caffeine consumption for 24 hours prior to experimental trial and to had a light meal 2h before their arrival.

Upon arrival, participants would have to wear running shoes, light and short running shorts and light cotton socks. Participants received comprehensive instructions about the shuttle run test and the whole process of measurements. Firstly participants answered the International Physical Activity Questionnaire (IPAQ). Thereafter, anthropometrics data (weight and height) were evaluated as well as the body temperature in external ear canal and axillary. All participants followed five minutes warming up and then performed to 20 m shuttle run test until their volitional limit. Once the participants could no longer run, the test was over and the number of laps was recorded. After the end of the shuttle run, were evaluated the body temperature and the weight of each participants. No fluids consumptions were permitted until the second weighing. They were weighed twice, at baseline and at the end of the running test with a precision weight scale (Kern DE 150K2D, KERN \& SOHN GmbH, Balingen, Germany).

Environmental data including air temperature and relative humidity were measured continuously using a portable weather station (LCD Digital Temperature \& Humidity Meter HTC-1). The weather station was placed 1 meter above the ground according to the manufacturer's guidelines.

Eligibility criteria: Inclusion Criteria:

* Healthy children and adults

Exclusion Criteria:

* Diagnosed chronic medical condition;
* Symptoms of acute illness;
* Recent (past 4 weeks) usage of medications known to affect the circulatory system, the thyroid, the pituitary function, or the metabolic status

Primary outcomes:
measure: Aerobic fitness level
timeFrame: Through study completion (a shuttle run test), an average of 15 minutes
measure: Change from baseline ear canal temperature
timeFrame: Change from baseline to the end of study completion (a shuttle run test), an average of 15 minutes
measure: Change from baseline axillary temperature
timeFrame: Change from baseline to the end of study completion (a shuttle run test), an average of 15 minutes
measure: Physical activity levels
timeFrame: Once before the shuttle run test
measure: Change from baseline body weight
timeFrame: Change from baseline to the end of study completion (a shuttle run test), an average of 15 minutes
measure: Change from baseline whole Body Sweat Rate
timeFrame: Change from baseline to the end of study completion (a shuttle run test), an average of 15 minutes
measure: Air temperature
timeFrame: Up to 30 minutes, during a one complete shuttle run test
measure: Relative humidity
timeFrame: Up to 30 minutes, during a one complete shuttle run test
Secondary outcomes:
Other outcomes:
Locations:
city: Trikala
country: Greece
facility: Department of Exercise Science, University of Thessaly
state: Thessaly
city: Tríkala
country: Greece
facility: FAME Lab, Department of Exercise Science, University of Thessaly
state: Thessaly
Study officials:
References: