The Effects of Walking with a Load in the Heat on Physiological Responses among Military Reserve Female Cadets

International Journal of Exercise Science 13(2): 900-911, 2020. This study aimed to investigate the effects of walking in a hot and humid environment while wearing a combat suit with a load on physiological responses among the Malaysian Military Reserve Officer Training Unit (ROTU) female cadets. Eight healthy female ROTU cadets (age: 21.3 ± 1.0 years old; height: 156.3 ± 4.9 cm; weight: 55.6 ± 7.5 kg) participated in this randomised, crossover trial. They walked for 1 h on a treadmill at 3 km.h-1 while carrying either 8.2 kg load (WL) or without load (WOL) in a room maintained at 30°C and 70% relative humidity. Heart rate, rate of perceived exertion (RPE), and tympanic temperature were recorded at regular intervals during the trials. Nude body weight was recorded before and after the walk to determine body weight loss and sweat rate. Urine samples were also collected before and after the walk to determine urine specific gravity of the participants. There was a significant main effect of time and interaction for heart rate (p \u3c 0.001) during the experimental trials. Tympanic temperature was significantly higher at 60th min in WL trial (p \u3c 0.05) compared to the WOL trial. Similarly, RPE was found to be significantly higher in WL trial (p \u3c 0.01) compared to the WOL trial. However, the percentage of body weight loss and sweat rate was significantly different between trials (p \u3c 0.05). Wearing a combat suit with a load showed significantly increased metabolic demands compared to wearing combat suit alone during prolonged walking in a hot and humid environment