THE EFFECTS OF WHOLE BODY HEATING ON LOCAL SKIN THERMAL SENSITIVITY IN YOUNG ADULTS ELLA ROSS-JEWELL
BSc (Hons) ERGONOMICS (HUMAN FACTORS DESIGN) +44 (0) 7454 137 273 e.ross-jewell-13@student.lboroo.ac.uk
EXPERIENCE
‘16 Bentley Motors Ltd - Ergonomics Placement
Does a warmer body impair or enhance thermal sensitivity? The aim of this study was to understand the relationship between increasing whole body temperature and local thermal sensitivity to a probe of varying temperature, applied in a dose dependent fashion. In this study eight participants, four males and four females were assessed. Each participant took part in two conditions. In the whole body heating condition 50°C temperature water was perfused through a thermal suit and on the other occasion 30° temperature water was used as a neutral condition. During the trials a thermosensory test was conducted whereby participants rated their perceived thermal sensation of five different temperature stimuli (± 8°C and ± 4°C from a baseline neutral of 30°C, including 30°C) applied to the back of the left hand. This thermosensory test was conducted before water was perfused through the suit, then every 10 minutes thereafter and then 10 minutes after a ‘cooling down’ period. The whole body heating protocol resulted in large increases in whole body, Tsk: 0 min: 33.08 ± 1.01°C (95% CI = 32.24 to 33.93), 10 minutes: 35.84 ± 0.82°C (95% CI = 35.15 to 36.52), 20 minutes: 37.41 ± 0.68°C (95% CI = 36.84 to 37.97) and 30 minutes: 37.69 ± 0.69°C (95% CI = 37.11 to 38.27) with no changes in rectal temperature over time (p=0.723).
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2017
LOUGHBOROUGH DESIGN SCHOOL
It was found that participants were less sensitive to skin warming during the whole body warming condition, so when Tsk increased, thermosensitivity to local skin warming from the probe decreased. However, thermosensitivity to local skin cooling remained unchanged. For the 34°C stimuli probe there was a significant difference between the two conditions (F=8.724, p=0.005) and the same for the 38°C stimuli (F=15.859, p=0.0001) with participants rating the stimuli less warm in the whole body heating condition. This identifies a new feature of human temperature integration whereby whole body thermal states have an impact upon local thermal sensitivity. This research has increased the understanding of human thermosensory integration and has highlighted areas in which research could be beneficial. These observations could be relevant in terms of occupational performance, such as military and fire service personnel where hand function under cold and heat stress within extreme environments is important. It may also play a role within the workplace looking at ways to improve thermal comfort through the application of local heating or cooling of the skin.
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