The physiological demands of horseback mustering when wearing an equestrian helmet

Abstract

The hottest months on northern Australian cattle stations are from September to November, and it is during these months that horseback cattle mustering occurs. Stockmen wear clothing that restricts heat loss, and protective helmets have recently been introduced. Anecdotal evidence points to the possibility that helmets may increase the probability of developing heat illness, or reducing workplace performance. In this project, we quantified the working (thermal) environment on such cattle stations, and measured the metabolic demands on, and concurrent physiological strain in stockmen during mustering, whilst wearing an equestrian helmet. During horseback work, the average heart rate was 102.0 beats min(-1) (SD 14.0), with almost 90% of the time (238 min) spent working at intensities <50% of the heart rate reserve. The projected metabolic heat production during mustering ranged between 178 and 333 W (women), and between 212 and 542 W (men). The average core temperature was 37.6 degrees C, while the mean skin temperature averaged 34.1 degrees C. It was concluded that the working environment is, on average, thermally uncompensable during the mustering season. However, horseback mustering per se is a relatively low-intensity activity, interspersed with short periods of high-intensity work. This activity level was reflected within core temperatures, which rarely climbed above values associated with light-moderate exercise. Thus, whilst the climatic state was uncompensable, stockmen used behavioural strategies to minimise the risk of heat illness. Finally, it was observed that the helmet, though unpleasant to wear, did not appear to increase thermal strain in a manner that would disadvantage stockmen.

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Application of Machine Learning Algorithm on MEMS-Based Sensors for Determination of Helmet Wearing for Workplace Safety

“…Although helmet researchers remain split on various thermal comfort interventions, helmet microclimate psychrometric response to helmet wearing consistently shows two distinct states between ambient and helmet microclimate parameters [ 1 , 3 , 7 ] due to metabolism and perspiration dissipation via a human wearer’s head. This provides an authentic and strong physiologically-based phenomenon for helmet wearing determination [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 ]. Besides psychrometry, other helmet safety research focused on enabling new levels of safety advisories by adding environmental hazard sensors with communication devices to sense for increasing danger [ 18 , 19 , 20 ] or brain-computer-interface with physiological sensors for emotion detection [ 21 ].…”