Heat Stroke
Conditions
Keywords
Active Cooling Device
Brief summary
This project investigates the effectiveness of pre-exercise active cooling using a temperature-controlled cooling vest in reducing heat-related physiological strain during endurance-type aerobic exercise in non-regularly trained ("weekend") athletes under hot and humid environmental conditions. Because these individuals often lack sufficient heat-acclimation training, they are at increased risk of excessive thermal stress, cardiovascular overload, and heat-related disorders during prolonged exercise. Using a controlled laboratory design, participants will perform moderate-intensity endurance exercise in a simulated hot environment, with or without pre-cooling intervention. Peripheral circulation and thermoregulatory responses will be assessed through laser Doppler flowmetry based skin blood-flow analysis and infrared thermography, alongside heart rate and perceived exertion measures. The study aims to clarify how active pre-cooling influences vascular regulation, sympathetic activity, skin temperature distribution, and exercise tolerance, and to evaluate its potential as a practical, non-fatiguing alternative to heat-acclimation training. The findings are expected to provide evidence-based guidance for reducing heat strain and improving exercise safety and comfort in recreational endurance athletes exercising in hot climates.
Detailed description
The primary aim of this study is to investigate the effects of pre-exercise active cooling using a temperature-controlled vest on peripheral vascular regulation mechanisms in non-regular endurance exercisers under hot environmental conditions. Specifically, this study seeks to quantify how pre-cooling modulates skin blood-flow dynamics, sympathetic nervous system activity, endothelial function, and myogenic vascular control, as assessed through frequency-domain analysis of laser Doppler flowmetry signals, before and after endurance-type aerobic exercise. By characterizing these microcirculatory responses alongside changes in skin-surface temperature measured via infrared thermography, the study aims to elucidate the physiological pathways through which active pre-cooling attenuates thermal strain and cardiovascular load during exercise in the heat.
Interventions
DEVICETEC Vest
Intervention 1: Active Pre-Cooling Vest Type: Device (active cooling garment) Timing: 30 minutes before exercise (pre-cooling period) Procedure: Participants wear the temperature-controlled vest in a hot/humid lab setting before the endurance aerobic exercise test. Purpose: Reduce thermal strain and cardiovascular load; improve comfort; modulate peripheral circulation responses.
OTHERNo Pre-Cooling (Without Vest)
Intervention 2: No Pre-Cooling Without Vest Type: No intervention / usual condition Timing: 30 min Duration Procedure: Participants rest quietly for the same pre-exercise duration without wearing a cooling vest, then complete the identical warm-up and exercise protocol.
DEVICEWater Cooled Vest
Type: Device (active cooling garment) Timing: 30 minutes before exercise (pre-cooling period) Procedure: Participants wear the water cooled vest in a hot/humid lab setting before the endurance aerobic exercise test. Purpose: Reduce thermal strain and cardiovascular load; improve comfort; modulate peripheral circulation responses.
Sponsors
Kaohsiung Medical University
Study design
Allocation
NON_RANDOMIZED
Intervention model
FACTORIAL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
20 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
* Age 20-50 years. * In the past 6 months, endurance exercise less than three times per week, 40-60 min each session. * No cardiovascular, metabolic (e.g., diabetes), or neurological disorders, and no diseases affecting vascular regulation. * No medication affecting vascular tone within the last 3 months. * No major musculoskeletal injuries or disorders affecting performance within the last 3 months.
Exclusion criteria
* • Diabetes, hypertension, or peripheral vascular disease. * Long-term work in hot environments. * BMI \> 30 kg/m², smoking, or heavy alcohol use. * Allergic reactions triggered by heat or cold (e.g., hives).
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Heart Rate | During a single laboratory visit lasting approx. 40 minutes: baseline immediately before the pre cooling period,immediately after 30 minutes of pre cooling,immediately after the 5 minute exercise bout, and immediately after the 5 minute seated cool down. |
| Temperature | During a single laboratory visit lasting approx.40 minutes: baseline immediately before the pre cooling period, immediately after 30 minutes of pre cooling,immediately after the 5 minute exercise bout, and immediately after the 5 minute seated cool down. |
Countries
Taiwan
Contacts
STUDY_CHAIRGuo LY Professor and Dean of College of Health Sciences, P.hD
Department of Sports Medicine, Kaohsiung Medical University, Taiwan
Outcome results
None listed