TEMPERATURE-DEPENDENCE OF MECHANICAL POWER OUTPUT IN MAMMALIAN (RAT) SKELETAL-MUSCLE

Force-velocity data at different temperatures (range, 10-35 degrees C) from intact fibre bundles are analysed to determine the temperature d ependence of the maximal mechanical power output of fast and slow rat muscles. At 35 degrees C, the maximal mechanical power was similar to 250 kW m(-3) (= 250 mu W mm(-3)) in fast (probably an underestimate) a nd similar to 100 kW m(-3) in slow muscle. Within the more physiologic al temperature range (25-35 degrees C), the temperature coefficient (Q (10)) of maximum power was 2-2.5. In both muscles, the maximal power a t 10 degrees C was only about 3-5 % of that at 35 degrees C,the decrea se being particularly pronounced at temperatures below 20 degrees C (Q (10) of 5-7).