None listed
Conditions
Brief summary
Water related recovery methods to treat hyperthermia (i.e. a highly elevated core temperature) are well understood, however dousing as a recovery method to reduce heat strain in contrasting humidities currently lacks experimental evidence. This study aims to build upon previous water dousing research by investigating the effect of water dousing upon the core temperature response following strenuous exercise in the heat under contrasting humidities. Based on theoretical data, we hypothesise that dousing in comparatively drier conditions will result in a greater decrease in thermal strain (core body temperature) compared to more humid conditions during recovery from exercise in the heat.
Interventions
Materials and procedures:
- 3 x session visits to the lab by each participant in total
- 1 x familiarisation session to complete an incremental test to exhaustion. The familiarisation session will occur 4-7 days prior to the first experimental session take approximately 3hours and requires participants to complete an incremental test to exhaustion and a 10 km time trial on the treadmill. The incremental test to exhaustion will be conducted in temperate conditions (22°C and 50% relative humidity)
Materials and procedures: - 3 x session visits to the lab by each participant in total - 1 x familiarisation session to complete an incremental test to exhaustion. The familiarisation session will occur 4-7 days prior to the first experimental session take approximately 3hours and requires participants to complete an incremental test to exhaustion and a 10 km time trial on the treadmill. The incremental test to exhaustion will be conducted in temperate conditions (22°C and 50% relative humidity) on a calibrated motorised treadmill at 1% incline with a metabolic cart to measure gas exchange. The test will consist of initial four minute submaximal steady state exercise intensities, followed by the speed of the treadmill increasing by 1 km/h every minute until volitional exhaustion. - 2 x experimental sessions to complete a 10 km time-trial on a treadmill. The dousing intervention is then applied after the completion of the time-trial during these two sessions. - Each session will take approximately 2-3 hours and are undertaken 4-7 days apart. - The dousing water will be administered at ~29 degrees as 1 x 400 mL douse immediately after the 10 km time trial and then followed by 4 x 200 mL douses every 6 min for a total of 30 min. The participant will place the water over their forehead whilst standing in a large bucket. After the dousing, the participant will remain seated in front of a fan that is 1.25 m away and set to 4 m/s. - 150ml of 38 degree water will be consumed by the participant at each dousing timepoint -A ingestible gastrointestinal temperature sensors is provided to the participants for consumption 6-8 hours prior to the two experimental sessions. The environmental conditions for the two experimental sessions will be: 1) 30°C and 45% relative humidity (1.91 kPa absolute humidity) 2) 28.5°C and 76% relative humidity (2.96 kPa absolute humidity) The minimum period of days that the intervention can be completed over is 11 days. A study calendar will be used to manage adherence to the study sessions. Who will deliver: A sport science graduate will lead data collection, and the remainder of the team are experienced researchers with 10-30 years of academic experience. Mode: In-person testing of individual participants Location: Environmental chamber at the University of South Australia
Sponsors
University of South Australia
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 55 Years
Healthy volunteers
Yes
Inclusion criteria
Trained long-distance runners who are: males and females aged between 18-55 and are training at leastthree times per week with local level representation
Exclusion criteria
Not passing Stage 1 of the Exercise Sport Science Australia (ESSA) pre-exercise screening tool.
Outcome results
None listed