I'm gonna head out. Can you lock up?
Lock the knee. It’s a thing we say sometimes. What the heck does it mean? Maybe it means a couple things. Maybe it means nothing. Lets break it down.
In standing balancing postures we are usually asked to make our standing leg straight/strong. This process can do wonders for the strength of your legs and hips especially when balancing on one leg.
When your leg is straight your bones will provide support for your body weight because they are stacked on top of each other and they are strong and made for that. When your knee bends your muscles must work harder to hold you up, and to support your joints.
Just like everything in yoga, the key is consciousness. It is possible for everyone with a knee joint to straighten their leg to it’s fullest range of motion and for the most part, turn off their leg muscles, this is hyper-extension of the joint. This creates extra stress on the joint, its supporting ligaments, and tendons.
By bending the knee, muscles engage, so you don’t fall over. However it is still possible to find the “sweet spot” between hyper-extension and falling over by bringing your attention to the knee and building balance in your asana by learning to use the balanced forces of your bones and muscles.