NCT05988606

Work Rate Adjustments During a High-intensity Interval Training on a Stationary Bike in a Hot and Temperate Environment

Acute Work Rate Adjustments During High-intensity Interval Training in a Hot and Temperate Environment

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 7 (actual)
• Sponsor: University of Alabama, Tuscaloosa · Academic / Other
• Sex: All
• Age: 18 Years – 39 Years
• Healthy volunteers: Accepted

Summary

The goal of this repeated measures study is to evaluate acute work rate adjustments during high-intensity interval training (HIIT) in a hot and temperate environment in healthy and active adults when using target heart rate to prescribe the exercise intensity. The main questions it aims to answer are: * Will HIIT based on target heart rate in a hot environment result in increased cardiovascular (i.e., elevated recovery HR) and thermal strain compared to HIIT in a temperate environment? * Will work rate be lowered to a greater extent during HIIT in a hot environment compared to a temperate environment in order to maintain target heart rate? * Will maximal aerobic capacity (V̇O2max) decrease to a greater extent after HIIT in the heat compared to a temperate environment? Procedures: Participants will complete 5 trials on a cycle ergometer. Trial 1 (Control Visit): Participants (n = 7) will have their maximal heart rate and V̇O2max measured in a temperate environment (\~22 °C, 40% RH). Experimental Trials 2-5: The order of the trials will be counterbalanced and randomly assigned to participants. * 15TEMP: Participants will cycle at 70% of their maximum heart rate for 8 minutes as a warm-up, followed by one round of HIIT. The HIIT protocol consists of 4 minutes at 90% of maximum heart rate followed by 3 minutes at 70% of maximum heart rate, totaling 15 minutes, in a temperate environment (\~22 °C, 40% RH). After the HIIT session, a graded exercise test will measure V̇O2max. * 15HEAT: Similar to 15TEMP, but participants will perform the HIIT protocol in a hot environment (\~35 °C, 40% RH). * 43TEMP: Participants will cycle at 70% of their maximum heart rate for 8 minutes as a warm-up, followed by the HIIT protocol repeated four times (4 minutes at 90% of maximum heart rate and 3 minutes at 70% of maximum heart rate), totaling 43 minutes, in a temperate environment (\~22 °C, 40% RH). * 43HEAT: Similar to 43TEMP, but participants will perform the HIIT protocol in a hot environment (\~35 °C, 40% RH).

Conditions

• High-Intensity Interval Training
• Heat

Interventions

Type	Name	Description
BEHAVIORAL	15 minutes of high-intensity interval training	Participants completed an 8 min warm-up and 1 round of high-intensity interval training
BEHAVIORAL	43 minutes of high-intensity interval training	Participants completed an 8 min warm-up and 5 rounds of high-intensity interval training
OTHER	Hot environment	Participants exercised in a hot environment, \~ 35 °C, \~40% relative humidity.
OTHER	Temperate environment	Participants exercised in a temperate environment, \~ 22 °C, \~40% relative humidity.

Timeline

• Start date: 2021-05-12
• Primary completion: 2021-11-14
• Completion: 2021-11-14
• First posted: 2023-08-14
• Last updated: 2023-08-14

Locations

1 site across 1 country: United States