2007, Piran, Slovenia

Environmental Ergonomics XII
Igor B. Mekjavic, Stelios N. Kounalakis & Nigel A.S. Taylor (Eds.), © BIOMED, Ljubljana 2007
THE HUMAN FOOT EXPOSED TO COLD : GENDER DIFFERENCES
IN TEMPERATURES AND SENSATIONS
Victor Candas, André Dufour
Centre d`Etudes de Physiologie Appliquée (CNRS), Strasbourg, France.
Contact person: candas@c-strasbourg.fr
INTRODUCTION
When humans face cold conditions, the body parts that mostly feel the cold are the head,
hands and the feet. Obviously, the feet are generally covered, but the feeling related to cold
feet induces real thermal discomfort (Fanger 1972). The feet are felt especially cold because
they are often in contact with the shoe sole which is also in direct contact with the cold
surfaces. In addition, it is generally admitted (popular doctrine) that ladies will complain more
than men from cold feet. However, the scientific literature does not provide much supportive
information (Harju, 2002; Hiltz et al., 1999). It may also happen that the thermal protection
constituted by the shoes is dramatically lowered, due to moisture in the shoe structure which
does not help in terms of thermal insulation and comfort.
The problem with the foot thermal sensation may depend on the fact that the foot has a
somewhat complex morphology. For example:
- the toes are small cylinders with high dry heat exchanges coefficients, and widely variable
perfusion
- the lateral parts of the foot are more muscular
- the dorsal part is more bony
- the plantar surface has hard skin, subject to high pressure linked to body weight.
Accordingly, the local foot temperatures and associated sensations may be various and
complex.
The aim of this study was to explore the thermal responses of the foot of males and females
exposed to cold, and the capacities of humans to estimate the thermal subjective sensations in
three conditions of similar heat losses at three levels of thermal foot insulation.
METHODS
Subjects: Fifteen males and 15 females (19-28 y) of standard body height and weight
volunteered for these tests (Table 1), after being informed of the general conditions and
potential risks of cold sensations. The protocol was approval by both the Alsace Ethics
Committee (#05/69) and the French Health Ministry.
Table 1: Anthropometrical data (±SD)
364
Age Height, cm Weight, kg Body area, m²
Males 23,3 (± 2,43) 180 (± 5,3) 73,8 (± 8,42) 1,93 (± 0,1)
Females 23,8 (± 2,65) 166 (± 3,8) 58,1 (± 5,13) 1,64 (± 0,1)
All experiments were carried out in a climatic chamber (described elsewhere), the feet of the
subjects were be placed in an insulated wooden box (L=66 cm, l=55 m, h=35 cm) and cooled
by six large ventilated Peltier elements (maximal cooling at –10°C). A reference condition
(bare foot at 14°C) was previously performed to evaluate the pain threshold, and to fix the