Bend the front knee, keeping the back leg straight, press the right heel down on the floor.

前腿膝关节弯曲，后腿保持绷直状态，右脚后跟贴紧地面并向下压。

youdao

Bend your knees and lower your back knee towards the floor, keeping the front heel down and the knee directly over the centre of the foot.

弯曲你的膝盖以及你的后腿膝盖向地面方向弯曲，保持前脚踝触地，以及膝盖在脚中心的正上方。

youdao

It slides up and down my heel when I walk around.

我一走动，它就在我的脚跟上下滑动。

youdao

Runners who wear shoes usually come down heel first.

VOA: special.2010.02.03

"Our study shows that the heel-down posture increases the economy of walking but not the economy of running, " says Carrier.

CNN: Running debate: Bare or in shoes?

The town is certainly down at heel by comparison with the nearby capital, though it has a mildly exotic flavour in other respects, including five tattoo parlours on the main street.

ECONOMIST: Japanese immigration

With their inflexibility, cushioning, and raised heels, they almost force you to crash down on your heel and send the impact of all your weight in every step straight into your knees and hips.

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