2007, Piran, Slovenia

Clothing
EFFECTS OF QUILT AND MATTRESS WADDING MATERIALS
ON BED MICROCLIMATE DURING BEDREST AT MILD
TEMPERATURES
Ritsuko Imamura 1 , Keiko Tsuchida 2 and Atsumi Morioka 2
1 Wakayama University, Wakayama, Japan, 2 Nishikawa Living Co. Ltd., Osaka, Japan
Contact person: ritsuko@center.wakayama-u.ac.jp
INTRODUCTION
Many studies on the sleeping environment have been published, and research on the
wadding materials of quilt or mattress has been one of the important characteristics
for obtaining comfortable sleeping conditions in either a cold or warm environment.
We have reported that clothing microclimate humidity, and the humidity between the
skin and mattress increase faster for cotton wadding than for polyester fabrics,
especially in the back skin area in a warm environment (Imamura, 2000). Tokura et al.
(1981) reported that total weight loss and local sweat rate were significantly greater
for cotton wadding than for polyester. Thus, hygroscopic properties appear to affect
the bed microclimate and thermoregulation in a warm environment. In a cold
environment, the effects of an electric blanket, for example (Imamura, 1987), were
reported in terms of thermoregulatory responses. However, the wadding materials of
futon (defined here as the quilt and mattress set) have not been studied extensively in
a cool environment because perspiration is not extensive. The purpose of this study
was to investigate how different quilt and mattress wadding materials affect
temperature regulation and bed microclimate during bedrest at mild air temperature.
METHODS
Ten young healthy male volunteers with a mean age of 21.8 ± 1.0 yrs participated in
this study. Their average height, weight and body surface area were 169.6 ± 5.7 cm,
63.5 ± 9.3 kg, and 1.67 ± 0.1 m 2 , respectively. Procedures were carefully explained,
and all participants gave their informed consent. The experiment was carried out using
a climatic chamber with an air temperature of 20 ± 2ºC and a relative humidity of 60
± 10%. The experiments were conducted for 150 min during the daytime, with the
comparison of 3 different hygroscopic wadding materials. Highly hygroscopic
waddings (HH) were down and feather in quilt material and wool in the mattress.
Moderately hygroscopic wadding (MH) was wool and polyester blended in both quilt
and mattress. The low type (LH) was polyester material. The experimental futon was
put in separate bag-type cotton sheets (which covered both quilt and mattress), and
then placed on a hard bed mattress. Each participant wore shorts and long-sleeved
cotton pajamas. The material order was randomized for each participant. All the
experiments began in the early afternoon.
Rectal temperature (Tre), skin temperature at 8 sites (forehead, chest, back, forearm,
hand, thigh, leg and foot), chest clothing microclimate (temperature and humidity),
bed microclimate near chest area, and each layer’s surface temperature and humidity
for futon in the trunk area were measured continuously in the supine position during
the 150 min experiment. Subjective thermal and comfort sensations were obtained
every 30 min and body weight was determined with an accuracy of 10 g before and
after the experiment and the body weight loss was calculated. Mean skin temperature
(MST) was calculated using the following equation.
MST = 0.07 Tforehead + 0.35 (Tchest + Tback) + 0.14 Tforearm + 0.05 Thand + 0.19 Tthigh + 0.13 Tleg+ 0.07
Tfoot
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