求翻译：两腿并拢站立，身体微微下蹲，两只手掌分别按住其相对应的膝盖，先按照逆时针方向旋转20次，再按顺时针方向20次，这个动作可以预防关节炎。是什么意思？

Legs close together and standing, the body slightly squat, two hands and hold the corresponding knee, in accordance with the first counter-clockwise 20 times, then clockwise 20 times, this action can prevent arthritis.

正在翻译，请等待...

Two legs gather stand, the body under squats slightly, two palms of the hand hold down separately the knee which its corresponds, defers to the counter clockwise to revolve first 20 times, then presses clockwise 20 times, this movement may prevent arthritis.

Stand legs joined body squatting slightly, each of the two palms press and hold the corresponding to its knees, first by 20 times counterclockwise, clockwise again 20 times, this action can prevent arthritis.