The lunge exercise good for Knee and thigh injuries

The lunge exercise:
The athlete stands with the injured leg a wide stance in front of the other. With the weight shifted onto the front leg, the back knee is slowly bent and dropped down towards the floor. The lunge position may be held to increase difficulty. Walking lunges are also a good progression.

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[SportsinjuryclinicNet]

It's a lunge, as stated in the title

[theunmodernwoman]

Can someone tell me what is this exercise called?