Combined effects of fabric air permeability and moisture absorption on clothing microclimate and subjective sensation during intermittent exercise at27 degrees C

The present paper aimed at determining the combined effects of two differen t levels of air permeability and moisture absorption, in terms of clothing microclimate and subjective sensation, in resting and exercising subjects a t an ambient temperature of 27 degrees C, a relative humidity of 50% and an air velocity of 0.14 m s(-1). Three kinds of clothing ensemble were invest igated: (1) polyester clothing with low moisture absorption and low air per meability (A), (1) polyester clothing with low moisture absorption and high air permeability (B)1 and (3) cotton clothing with high moisture absorptio n and high air permeability (C). The subjects exercised for 10 min on a cyc le ergometer at an intensity of 30% maximal oxygen uptake and then had a 10 min rest. This sequence was repeated four times. The main findings are sum marized as follows: (1)The clothing microclimate humidity in the back area was significantly higher in A than in B, and in C than in B. (2) The clothi ng microclimate temperature in the chest area was significantly higher in B than in A, and in B than in C. (3) The clothing microclimate temperature i n the back area was significantly higher in C than in B. (4) The clothing s urface temperature was significantly higher in C than in B. (5) Although th e positive relationships between the microclimate humidity and forearm swea t rate was significantly confirmed in all three kinds of clothing, the micr oclimate humidity at chest for the same sweat rate was lower in C than in A and B. (6) Although the positive relationships between subjective sensatio n and forearm sweat rates were significantly confirmed in all three kinds o f clothing, the subjective discomfort seemed to be reduced more effectively in C than in A and B for the same sweat rate, These results were discussed in terms of thermal physiology and combined effects of air permeability an d moisture absorbency of the fabrics.