The effect of ice-slushy consumption on plasma vasoactive intestinal peptide during prolonged exercise in the heat

• The effect of ice-slushy ingestion on body temperature and plasma VIP was examined.
• Skin temperature was lower with ice-slushy consumption.
• Plasma VIP was not changed with cold beverage ingestion.
• There was a correlation between plasma VIP and rectal temperature.

The aim of this study was to determine the effect of exercise in the heat on thermoregulatory responses and plasma vasoactive intestinal peptide concentration (VIP) and whether it is modulated by ice-slushy consumption. Ten male participants cycled at 62% V̇O2max for 90 min in 32 °C and 40% relative humidity. A thermoneutral (37 °C) or ice-slushy (−1 °C) sports drink was given at 3.5 ml kg−1 body mass every 15 min during exercise. VIP and rectal temperature increased during exercise (mean±standard deviation: 4.6±4.4 pmol L−1, P=0.005; and 1.3±0.4 °C, P<0.001 respectively) and were moderately associated (r=0.35, P=0.008). While rectal temperature and VIP were not different between trials, ice-slushy significantly reduced heat storage (P=0.010) and skin temperature (time×trial interaction P=0.038). It appears that VIP does not provide the signal linking cold beverage ingestion and lower skin temperature in the heat.