You hear this all the time in exercise. Don't lock your knees! Oh my gosh they shouldn't be locking their knees doing that, they will get injured! It's not black and white people!
Knee health: There is a muscle on the inside of you're knee and the bottom of your quadriceps called the Vastus medialis oblique or V.M.O. It's one of the main stabilizers for the patella tendon!
In order for this muscle to work well it needs to be in full extension or locked. Some other functions of the V.M.O are to extend your knee forward during walking or running and also assist in stopping the knee from caving inwards which will cause injury!
If you are someone who is hypermobile yes I would suggest not locking your knees or someone who may have a very limited amount of or damaged Cartlidge maybe not too.
Try this throughout the day to build the V.M.O endurance sounds simple but it works. When standing lock your knees for 5 minutes periodically. Make sure you don't push your pelvis too far forward as this will put stress on your lumbar spine.
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