Thermal and cardiovascular strain imposed by motorcycle protective clothing under Australian summer conditions.
Motorcycle protective clothing can be uncomfortably hot during summer, and this experiment was designed to evaluate the physiological significance of that burden. Twelve males participated in four, 90-min trials (cycling 30 W) across three environments (25, 30, 35 °C [all 40% relative humidity]). Clothing was modified between full and minimal injury protection. Both ensembles were tested at 25 °C, with only the more protective ensemble investigated at 30 and 35 °C. At 35 °C, auditory canal temperature rose at 0.02 °C min(-1) (SD 0.005), deviating from all other trials (p < 0.05). The thresholds for moderate (>38.5 °C) and profound hyperthermia (>40.0 °C) were predicted to occur within 105 min (SD 20.6) and 180 min (SD 33.0), respectively. Profound hyperthermia might eventuate in ~10 h at 30 °C, but should not occur at 25 °C. These outcomes demonstrate a need to enhance the heat dissipation capabilities of motorcycle clothing designed for summer use in hot climates, but without compromising impact protection. Practitioner's Summary: Motorcycle protective clothing can be uncomfortably hot during summer. This experiment was designed to evaluate the physiological significance of this burden across climatic states. In the heat, moderate (>38.5 °C) and profound hyperthermia (>40.0 °C) were predicted to occur within 105 and 180 min, respectively.
a Neuroscience Research Australia , Sydney , Australia.
Liz
L
de Rome
b Centre for Human and Applied Physiology, School of Medicine , University of Wollongong , Wollongong , Australia.
Elizabeth A
EA
Taylor
c School of Psychology , University of Wollongong , Wollongong , Australia.
Rodney J
RJ
Croft
a Neuroscience Research Australia , Sydney , Australia.
Julie
J
Brown
d Monash Injury Research Institute and Monash University Accident Research Centre , Monash University , Melbourne , Australia.
Michael
M
Fitzharris
b Centre for Human and Applied Physiology, School of Medicine , University of Wollongong , Wollongong , Australia.
Nigel A S
NA
Taylor
D000328:Adult; D001315:Australia; D005334:Fever / Q000209:etiology*; D006339:Heart Rate; D006358:Hot Temperature / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009049:Motorcycles; D010101:Oxygen Consumption; D010865:Pilot Projects; D011481:Protective Clothing; D012621:Seasons; D012881:Skin Temperature; D013546:Sweating
Core temperature; heat loss; heat strain; metabolic heat production; motorcycle clothing; protective clothing; protective equipment