400 meters is not running at full speed, but distributing your physical fitness reasonably. Generally, you start running at full speed after the last corner, and the straight is the best embodiment of your ability to keep turning speed.
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400-meter running skills:
First of all, you should allocate your physical fitness reasonably, and do the exercise at what speed according to the standard of dividing each stage. Only in this way can you finish 400 meters reasonably. The first corner starts at full speed, and slows down slightly when turning. The first straight runs with 95% strength, striding with high center of gravity, and slightly increasing the pace frequency and length after turning, so as to improve the speed without wasting physical strength.
The second turn picked up speed. After half bending, run at full speed until the sprint begins. At the most difficult moment, the molars keep striding and the center of gravity drops slightly. After drawing the curve, the forced speed is advanced, and the weak acceleration is 90% behind. The center of gravity inclines inward as a whole. The swing arm has a small inner amplitude and a large outer amplitude, and the starting line is along the tangent direction.
Baidu encyclopedia -400-meter race