| Abstract: | In this study, we examined the effects of upper-body pre-cooling before intermittent sprinting exercise in a moderate environment. Seven male and three female trained cyclists (age 26.8±5.5 years, body mass 68.5±9.5?kg, height 1.76±0.13?m, Vdot]O2peak 59.0±11.4?mL?·?kg?1?·?min?1; mean±s) performed 30?min of cycling at 50% Vdot]O2peak interspersed with a 10-s Wingate cycling sprint test at 5?min intervals. The exercise was performed in a room controlled at 22oC and 40% relative humidity. In the control session, the participants rested for 30?min before exercise. In the pre-cooling session, the participants wore the upper segment of a liquid conditioning garment circulating 5oC coolant until rectal temperature decreased by 0.5oC. Rectal temperature at the start of exercise was significantly lower in the pre-cooling (36.5±0.3oC) than in the control condition (37.0±0.5oC), but this difference was reduced to a non-significant 0.4oC throughout exercise. Mean skin temperature was significantly lower in the pre-cooling (30.7±2.3oC) than in the control condition (32.5±1.6oC) throughout exercise. Heart rate during submaximal exercise was similar between the two conditions, although peak heart rate after the Wingate sprints was significantly lower in the pre-cooling condition. With pre-cooling, mean peak power (909±161?W) and mean overall power output (797±154?W) were similar to those in the control condition (peak 921±163?W, mean 806±156?W), with no differences in the subjective ratings of perceived exertion. These results suggest that upper-body pre-cooling does not provide any benefit to intermittent sprinting exercise in a moderate environment. |
