Movement is rooted in the feet, generated in the legs, controlled by the waist, & functions through the fingers. The feet, legs and waist must always act in unison, in order to move with precision and gain an advantage.
其根在腳，發於腿，主宰於腰，行於手指，由腳而腿而腰，總須完整一氣，向前退後，乃能得機得勢。
-The Theory of Taijiquan by Zhang Sanfeng
This describes the basic functions of the lower body. The feet provide the base & stability, the legs generate the movement, and the waist directs that movement. All this must be coordinated as one.
Note: Some translations use the term Qi (energy) or Jin (force) instead of movement. All are correct. Focus on movement first and the others will come.
Root at the Feet Drill
1. Sit down. Lift your feet off the ground and roll them in all directions. Slow and gently. Twist and turn them. Move your ankles and toes through their fullest range of motion and experience what that feels like.
2. Stand up. Tense your feet then relax them. As they relax, feel them spread out and conform to the surface you are standing on. Repeat this several times with deep relaxation each time.
3. Continue repeating step 2. Begin adding the ankles, then the calves and eventually the entire leg into the tensing and relaxation. Each time you relax let the bottom of the foot expand and open. Let gravity pull the tension, weight, and Qi down your legs and out the bottoms of your feet. Let that sensation continue downwards as deep as it will go.
4. Now include the hips, waist, lower back and belly. Bending the knees and leaning forward slightly may help.
5. Relax. Let the feet expand and press into the ground. Let the weight of your body sink and settle down into and through your feet.
6. Keep your feet relaxed and firmly pressed into the ground by your weight. Begin to move your ankles. Slowly rock your body in a circle using your feet. The knees and waist may need to adjust a little for balance but keep that to a minimum. Get the largest range of motion you can using just your feet and without falling over.
If you feel top heavy, relax. Let that weight sink down into and through the feet.
Directed by the Waist Drill
1. Stand with feet shoulder width apart. Bend your knees and bring your hips under you as if sitting down. Drop about 3 – 6 inches below your normal standing height.
2. Make sure your feet are pointed forward or only slightly out and make sure your knees are lined up with your feet. This should be a comfortable position with no twisting or unusual pressure on the knees.
If you have physical issues that require a different toe/knee alignment, then adjust as needed.
3. Make sure your knees do NOT twist. This is very important. The knee is meant to bend and straighten. It is NOT meant to twist. Your toes, knees and hips should all be lined up and they should STAY that way during this ENTIRE exercise.
4. Keep your hips forward. Slowly turn your upper body and look to your right. Then your left.
Most of the twist should come from your belly and lower back (this is what we are calling the waist) above your hips. The hips, pelvis, knees & toes all stay facing forward with no twisting.
5. Go slow and pay attention to what this feels like. Bend your knees more and experiment with different stances. Wider, narrower, one foot forward. Expand your range of motion without letting your knees twist.
Generated at the legs
The legs are very powerful so they do the heavy lifting.
However, the knees only bend and straighten. They never twist. The knee can move up and down forward and back. It should never twist or move side to side.
The knee can be behind the toes or in front of the toes. It should never be inside the toes or outside them.
How to turn the foot
Sometimes a stance will require that the feet point in different directions so you will need to rotate the leg.
This rotation should come from the hip.
Opening the hip exercise.
1. Stand next to a stable wall or railing and brace yourself with one hand.
2. Raise one leg off the floor so that your knee and hip are both at 90 degree angles and your thigh is parallel to the floor.
3. Slowly swing your leg outward away from your other leg. Feel your hips open in the front and close in the back.
4. Bring your leg back the other way so that is crosses in front of your body. Feel the hips close in the front and open in the back.
Slowly and gently expand your range of motion and get a feel for the movement.
When you need to turn your feet in Tai Chi forms or movement remember what this feels like and turn from the hip without any torque on the knee.
Moving as a Unit.
This will require time and practice.
Practice your form without using your hands. Just focus on your stances and stepping. Pay attention to the feeling of your feet on the floor and moving from the ankles. Twist and rotate from the waste.
As you get more comfortable with this make sure everything is moving at once. Lookout for any awkwardness in movement and any areas that are not a coordinated part of the whole.
Chan Si Jin & Spirals
Spirals are an integral part of Taijiquan and should always be present throughout the entire body.
If you have not trained in this yet don’t worry about it. We’ll get to it later.
The spiral principles and the straight alignment of the knee coexist in harmony. One does not negate the other.
As you work your spirals, make sure it is allowed to pass through the leg without putting any twisting pressure on the knee.
This may seem counter intuitive but with practice the spirals will help you better connect the lower body, get more power from it, and make it easier to keep proper alignment that protects the knee.