The youtube videos below tend to focus on leg strengthening exercises and poses as well as exercises and or muscle activations for protecting your knees and for dealing with knee pain.
The long hip muscles connect from the lower leg bones (tibia and fibula) to the four corners of the hip bones (ASIC, PSIC, pubic bone, Ischial tuberosity).
Working from a rotationally stabilized shin, these muscles can be used to rotate and otherwise control the hip bone.
Since the sartorius, recturs femoris, tensor fascia latae/IT band and Gluteus maximus/IT band all pass over the vastus muscles, activating the vastus muscles (as well as the adductors) can help to take out the slack from these muscles making rotation control of the hip bone relative to the thigh (or vice versa) easier.
The external obliques can be used to add tension to the inguinal ligament.
One reason for doing this is to help anchor the front of the hip bone. Doing this, gives the muscles that attach at or near to the ASIC and pubic bone an anchor point.
These muscles include shorter hip muscles like: iliacus, pectineus and gluteus minimus.
They also include long hip muscles like: the sartorius, rectus femoris, tensor fascia latae and gracilis.
Because these long hip muscles cross the knee joint, creating an upward pull on the inguinal ligament may be part of effectively dealing with knee pain.
I've had IT Band Knee pain, particularly while doing weighted front squats, and my method for alleviating that pain was to activate particular muscles while squatting.
One method involves adding tension to the IT Band by activating the Vastus Lateralis muscle.
Another method involves anchoring the bottom end of the IT Band by either activating the Tibialis Anterior directly or by activating it indirectly by stabilizing the heel.
This is a version of the Peterson squat that I've been practicing for the last month or so. Basically, it's a squat on one leg with the heel lifted.
While it's generally not recommended to do this exercise if you have knee problems, I've been using it despite my knee problems. And that's what I talk about in this video, how to do the Peterson squat safely even if you do have knee problems.
The main thing is to do it slowly and within a comfortable range of motion.
So that you can gradually extend that range of motion, in this video I talk about the various muscle control actions that I use to make my knees pain free.
First a couple of simple techniques so that you can deliberately contract your glutes.
Next some exercises where you can exercise both your glutes (hip extensors) and your psoas (hip flexor).
I had a question about whether it was "safe" to squat or pistol squat if flat footed. Here's my answer.
If you have collapsed arches, these exercises can be used to help "reshape" your foot.
Even if you don't have collapsed arches, these exercises can help improve foot awareness.
If you have true flat feet these exercises probably won't work to reshape the foot, but may help improve foot awareness.
For stronger knees (and for dealing with knee pain), an alternative to the Peterson squat is a "heels lifted" squat.
In this case, use the calf muscles to keep the heels lifted, particularly the gastrocnemius which cross the back of the knee joint to attach to the femur.
Do practice balancing on your forefeet without weight first.
One advantage of squatting with both legs is that I can go all the way down (butt to heels).
Note that I'm doing this to help deal with knee pain. However, I'm also doing it slowly and carefully.
Check out previous videos below on adding tension to IT Band, Inguinal Ligament Tension, Hip Rotation using long hip muscles.
The exercises in this video focus on body awareness and leg strength.
The first is a simple balancing on one leg foot touch. The idea is to touch the lifted foot lightly to the floor.
The second is a knee touch, lowering the back knee to the floor just to the point that skin contact is made. Both exercises help you practice body awareness.
I've included a simple modification for the split squat knee touch.
Because exercises like the Seated Get Up can tighten the calfs (since you use them for knee stability), this active calf stretch can be used to stretch them.
Because this is an active calf stretch the tibialis anterior muscle is strong exercised. You may find that it stretches your hamstrings also.
A variation of the Seated Get Up (which was like a one leg squat starting from a seated position), this exercise uses both legs.
It could be thought of as an exercise for getting up off of the floor without using your hands.
It can be a fun exercise to use as part of a seated warm up.
It also includes a variations that exercise the arms as well as the legs.
The seated get up is a variation of the one leg squat but starting from a seated position.
For knee strength and stability, the key point is activating the gastrocnemius muscle prior to lifting the back leg.
This video goes over some muscle activations you can do while in the deep squat to make it more comfortable for your knees.
It also includes tips for comfortably shifting weight to one foot and moving into the low position of the pistol squat.
Interested in learning how to feel and control your leg muscles?
Sensational Leg Anatomy includes a series of videos teaching simple muscle control exercises. The whole series teaches you to feel and control the major muscles of the legs from the hip bones down to the toes.
You can also get it as part of the Muscle Control Package(Learn to Feel Your Body)
Muscle control not only helps you to control your body, it also helps you to feel it making it easier to balance, improve flexibility and deal with pain and poor posture.
The dance of shiva is handy if you are interested in improving upper body balance and coordination.