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 dependence 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) and similar to 100 kW m(-3) in slow muscle. Within the more physiological temperature range (25-35 degrees C), the temperature coefficient (Q(10)) of maximum power was 2-2.5. In both muscles, the maximal power at 10 degrees C was only about 3-5 % of that at 35 degrees C,the decrease being particularly pronounced at temperatures below 20 degrees C (Q(10) of 5-7).