Dynamische leistungsfähigkeit bei reduzierter wärmeabgabe in feuerwehrschutzanzügen

The influence of reduced heat exchange during work in firefighter protective equipment upon the maximal dynamic power was examined. Wearing sports clothing, six professional firefighters (37 ± 12 years) first performed a graded walking test on a treadmill, including spirometry and blood lactate determination (La). Thereafter, under breathing protection (self-containing breathing apparatus), they performed three further treadmill tests to exhaustion in conventional firefighter clothing (SA), in chemical protective clothing without (CSA) and with external air supply (CSAeL), in randomized order with an interval of two days between runs. Heart rate (HR), rectal temperature (TR), temperature of skin (HT) were measured, as well as temperature (UT) and humidity (UF) in the suit. Compared to sportswear (4 W/kg body weight), a significantly lower maximum performance was reached in all protective clothings (3,1 W/kg in SA, 2,9 in CSA and 2,8 in CSAeL) at the same HR, but with significantly lower La. TR was 0,2 ° C higher than in sportswear, the sweat loss was same under all conditions. Submaximal at same workload, HR, TR and HT were higher in all protective clothings than in sportswear. In CSA and CSAeL HT and UT were lower compared to those in SA, however without any effect on the physiological parameters. We suppose that the cause of the reduced maximal power in firefighter equipment is the increased skin circulation with reductions of the muscle blood flow, and also the decreased breathing volume when using the breathing apparatus.