The back knee will go towards the second baseman.
If the back knee folds underneath then they are bugsquishing and not getting a good weight transfer.
Straightleg
Especially for the female the knee starting towards where the second baseman normally plays ( as a RH and shortstop for LH ) is important due to the increased width of the hip and width between the legs being wider. The knee cap is a good indicator of this.
Note: You can test for this your self by placing your back hand on a wall to brace your self so you can lift your back leg off the ground and take the knee towards the second baseman's normal playing position. Then repeat and point the knee towards the pitchers position. General guide line is if the thighs touch on the female you have lost your power.
Males having a smaller hip width and are width between the hips is narrower which allows the knee to be more under them.
Many Asian girls in general in my opinion have less hip width such as Jen Yee and can bring it more under them.
Also as you begin to do the Elvis move keep the front knee soft or flexed.
Thinking slow to load and soft to step on a flexed front knee helps.
Some hitters lock it out too soon and that can effect bat on ball location. Do it in front of a mirror and if you lock it up too soon you will see your head/ body get taller. Driving with the back knee at just the right moment is the art of hitting with power in my opinion. Softer is better than locked out.
Getting to the contact point with a soft knee in my opinion works well verses slamming the heel down too soon.
Howard
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