Thanks for the correction. Maybe I have to rephrase a bit, it is not shakiness but outright bad form, for example when you do squats or deadlifts and your knees

Thanks for the correction. Maybe I have to rephrase a bit, it is not shakiness but outright bad form, for example when you do squats or deadlifts and your knees move inwards, it is because of a weak vastus medialis [0] (had to google that), which is a stabilizing muscle, not the main muscle involved in squats. [0]: https://en.wikipedia.org/wiki/Vastus_medialis https://en.wikipedia.org/wiki/Vastus_medialis