Augmentation Index Predicts the Sweat Volume in Young Runners

Area of Science:

• Physiology
• Cardiovascular Health
• Exercise Science

Background:

• Sweating during exercise is regulated by various factors, but the link between vascular arterial stiffness and sweat volume in young adults is not well understood.
• Understanding these relationships can help identify physiological predictors of thermoregulation during physical exertion.

Purpose of the Study:

• To identify pre-exercise hemodynamic parameters that predict sweat volume during exercise.
• To determine post-exercise parameters predictable by sweat volume.
• To investigate the role of vascular arterial stiffness in regulating sweat volume.

Main Methods:

• Eighty-nine healthy young adults (21.9 ± 1.7 years, 51 males) performed a 3-km treadmill run.
• Collected demographic, anthropometric, and hemodynamic data (heart rate, blood pressure, pulse wave analysis).
• Measured sweat volume as pre- to post-exercise body weight difference; collected post-exercise hemodynamic data.

Main Results:

• Sweat volume correlated with gender, body surface area (BSA), peripheral systolic blood pressure (SBP), and pulse pressure (PP).
• Inverse association found between sweat volume and augmentation index at 75 bpm (AIx@HR75) and ejection duration.
• BSA predicted central PP; central PP and AIx@HR75 further predicted sweat volume. Peripheral SBP change was also associated with sweat volume.

Conclusions:

• Sweat volume during a 3-km run is influenced by hemodynamic parameters, including vascular arterial stiffness and central pulse pressure.
• Findings suggest that vascular arterial stiffness plays a role in regulating sweat volume during exercise.