The Effects of High- and Low-Dose Aspirin on Thermoregulation During and After Acute Cold Exposure

Abstract

To explore the effect of aspirin on the thermoregulatory responses of men during exposure to 12°C air (acute cold exposure) for a period of 120 minutes and recovery in 25°C air (rewarming) for 120 minutes. Seven male subjects (26.1 ± 2.4 yr) underwent pre-experimental testing to determine peak VO(2) and body composition. Participants underwent 3 trials in which they ingested the following for 1 week prior to each experimental trial: a capsule filled with cellulose (placebo), 81 mg · day(-1) of aspirin (low-dose aspirin), or 650 mg · day(-1) of aspirin (high-dose aspirin). Each trial consisted of a 30-minute baseline period, 120 minutes of exposure to 12°C air, and 120 minutes of recovery in 25°C air. Mean skin temperature and rectal temperature (T(re)) were measured, and heat production was calculated. During both acute cold exposure and rewarming, analysis of variance revealed a main effect for time (P < .05) with respect to T(re), mean skin temperature, and heat production. However, there were no significant differences between the treatments or treatment by time interactions. These data demonstrate that aspirin had no significant effect on the thermal and metabolic responses during acute cold exposure and rewarming.