For singing, you want to engage the entire body in making sound. The legs are your support system, and you want them to hold you up without tightening. Try the following suggestion to discover how to engage your legs.
To feel the legs engage as you sing, use a plié as you take the breath. Plié means “to bend,” and you want to bend your knees as you inhale. This bending helps you feel an opening sensation through your body and down into your legs. As you sing, you can gradually stand back up from the bend.
With each new breath, plié again to create the opening sensation in your legs and gradually stand back up. After you practice this way for a few weeks, you’ll be able to sing your song and bend or plié as you inhale. If you visualize that you’re bending, you feel your legs open as you inhale and engage as you sing.
For singing, you don’t want to lock your knees, or push your knees back. Locking your knees also locks your lower back, and you want your lower back to open for inhalation.
Instead, you want to keep your knees released. Released knees aren’t locked — but they’re also not bent. To find the difference between released knees and bent knees, stand and lock your knees. Without bending the knees, release the muscles around them.
Lock the knees again, and when you release the muscles, bend your knees. Move back and forth from the locked position to the bent position. You want to feel the released position, which is between locked and bent. Bent knees make you a little shorter. Released knees keep you the same height, without tight muscles around your knees.
To prevent tension in your knees, you can visualize a spring in your knees or pretend that you have oil in your knees, like the Tin Man in the Wizard of Oz, so that they move smoothly. Try using the visual of the spring to feel the difference between weight evenly distributed through the legs and feet and sinking your weight into your legs and knees and creating tension.