Date of Award


Document Type

Open Access Master's Thesis

Degree Name

Master of Science in Kinesiology (MS)

Administrative Home Department

Department of Kinesiology and Integrative Physiology

Advisor 1

Jason R. Carter

Advisor 2

John J. Durocher

Committee Member 1

Yeonwoo Rho

Committee Member 2

Scott Lempka


The influence of thermal stimuli on the sympathetic nervous system is variable and largely depends on the change in temperature and timing of the stimuli. Core temperature changes yield increased muscle sympathetic nerve activity (MSNA) while changes in skin temperature yield variable MSNA responses. The MSNA responses to acute heating or cooling sensations remains unclear. Twenty-three participants (11 women, 12 men; age 24±1 years, BMI 26±1 kg/m2) underwent a thermal protocol that included four trials each of cool sensation threshold, warm sensation threshold, and heat pain (12 total trials). Continuous blood pressure (finger plethysmography), heart rate (electrocardiography), and MSNA (via microneurography) were recorded throughout all trials. Data was assessed with a Shapiro-Wilk test and log transformations were utilized for non-normal distributed data. T-tests were used to compare physiological data for cool and warm sensation thresholds, and repeated measures ANOVA to compare multiple heat pain data points. MSNA was significantly attenuated during the immediate recovery of cool threshold and warm threshold. MSNA was inhibited during the sensation of heat pain and systolic arterial pressure was reduced during the recovery from heat pain. There were no significant differences between men and women for any variables and responses. These results indicate that acute thermal sensations result in the inhibition of MSNA.