Introduction: Short term heat acclimation (STHA) reduces thermal strain and perceptions of heat stress, which enhance performance and wellbeing in the heat. Two of the indicators for heat adaptation are an increased sweat rate (local and whole body) and a decreased amount of sodium chloride concentration in the sweat. Therefore, this study aimed to investigate the validity of different sweat analysis techniques after 5 days of STHA. Methods: Nineteen healthy individuals (age: 41 ± 23 years, body mass: 74.0 ± 12.2 kg, height: 174.9 ± 6.9 cm) [male; n = 15, female; n =4] completed seven trials over a three week period, in a controlled chamber set to 35°C, 50% relative humidity for all sessions. The pre and post tests were separated by five consecutive controlled hyperthermia heat acclimation sessions. Sweat analysis was compared from pre and posts tests, whereby whole body sweat rate (WBSR) was assessed via pre and post nude body mass. Local sweat rate (LSR) was determined via technical absorbent patches (TA) (weighed pre and post) and a wearable KuduSmart (SMART) monitor which was placed on the left arm during the 30 minutes of exercise. Tegaderm patches, used to measure sweat sodium chloride composition (SC), and TA patches were placed cycling on the back, chest and forearm for the 30 minutes. Results: Sudomotor function significantly adapted via STHA (p<0.05); demonstrated by a WBSR increase of 24%, LSR increase via the TA method (back: 26%, chest: 45% and arm: 48%) and LSR increase by the SMART monitor (35%). Finally, SC decreased (back: -21%, chest: -25% and arm: -24%, p<0.05). Conclusion: All sweat techniques are valid as they successfully identified sudomotor function adaptations following STHA. The real time data given by the wearable KuduSmart monitor provides greater sweat analysis detail than routinely used sweat analysis techniques.
|Publication status||Published - Oct 2018|