1, different postures:
When the frog retracts its legs, it keeps its body in a horizontal posture. Breathe with your head up, while your shoulders are still underwater, and your hips are always close to the water. Look up and inhale.
When the wave frog retracts its legs, its head and shoulders will rush out of the water. The hips are deeper. The body posture is inclined. At the end of the kick, lift your hips slightly.
2. Different leg contraction ranges:
The flat frog's thigh is greatly retracted. At the end of calf adduction, the thigh and trunk form an angle of 120 ~ 140, and the knee is about the same width as the hip joint. The thigh and calf form an angle of 40 ~ 45.
Unlike the wave frog, the angle between the leg and the trunk is larger. Because the shoulders and back are lifted out of the water, the hips and legs sink, the thighs retract slightly, and the calves and feet will not be exposed to the water.
3, the action rhythm is different:
Different from the "paddling" rhythm of the flat frog, the coordinated rhythm of the wave frog is "paddling". Forward stroke is the unique feature of wave breaststroke.
It happens between the end of the internal stroke and the start of kicking, when the hands and forearms are just on the horizontal plane and extend forward quickly parallel to the water surface. The chest and back are arched at the beginning of the stroke and arm extension, and the back is arched when rushing forward.
The wave frog pulls up the upper body by changing the water with the high elbow, grips the elbow with the falling momentum of the upper body, and quickly stretches forward in a slightly downward direction, then grips the frog leg and makes a slight whipping action. To be precise, it looks more like a dolphin's leg. The speed of wave frog is obviously faster than that of flat frog, but it consumes a lot of physical strength.
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