The Correct Biomechanical Use of the Feet & Knees | Part 1: Foot Posture

If you were to survey all the classical literature on taijiquan in the last hundred years, you will find very little information on the use of the feet and knees. The little that is said, however, is of extreme importance, yet it is surprising how few taijiquan practitioners, or teachers for that matter, are aware of the correct use of the feet and knees.

My taijiquan teacher Li Shao Qiang (Rose Li) once said that her teacher Deng Yung Feng (1873-1941) used to say that in order to assess the level of competence of an internal martial artist all one had to do was to look at the way he used his feet. If this wasn't correct there was no point in looking further. For however fancy or dazzling his forms looked they lacked substance and real power.

Wong Kiew Kit in his book reports an alarming statistic relating to knee injuries. Dr Jay Durbar in her doctoral thesis (1991) found that in a study of 216 taijiquan teachers in the United States, 60% of them reported knee injuries in themselves or their students as a result of practising taijiquan. Wong, however, points out that in his experience he found that taijiquan practitioners in Europe and Australia had no complaints of knee injuries. Still let this be a cautionary tale to us in Britain for the incorrect use of feet and knees will surely lead to knee injuries.

What then is the correct biomechanical use of the feet and knees in order to prevent injury, build stability and power and to develop that much talked about but rarely seen quality of "root"?

Foot Posture

First check that your foot posture is correct. Stand naturally with your feet together, balls of feet and heels touching. If there is a one to two finger width gap (" to 1") between your ankle bones your foot posture is correct. If your ankle bones touch you have collapsed arches and your weight is on only two points, the ball of your foot and your heel.

If you unlock your knees (you should never hyperextend them) and rotate your legs outward a little until there is at least a finger width gap between the ankle bones you will now notice that you have suddenly developed arches. You will also realise that you are on three points of balance - the heel, the head of the fifth metatarsal and the ball of the foot. This is correct foot posture. For those of you whose ankles touch a good "memory hook" is to remember to keep your weight on the outside edge of the foot (but not so far over that the ball of the foot comes off the floor) whenever you are standing, walking or running.

Now test your stability. Assume a fairly high horse stance, feet shoulder width apart. Let your ankles drop in and get a partner to push you from the side. You will find it impossible to resist the push. Now shift your weight towards the fifth metatarsal until your weight is firmly on three points of balance. Repeat the test. This time you will have no difficulty in resisting your partner's push and you will be pleasantly surprised at how rooted and stable you feel.

You will also notice that with the weight correctly placed your tail-bone tucks in naturally, the lumbar curve of the spine is reduced, the waist feels more "open", the chest will automatically "sink" down and the Dantien will relax and expand. Your hip joint, knee and second toe alignment (the axis of the foot should be measured on a line from mid-heel through the second toe) and these lines should be parallel in a normal or horse stance) will also be correct. Now check your foot posture in a forward stance. As long as your knees point in the direction of your second toes your foot posture will be correct. It's the back knee and foot you should pay special attention to. If the weight goes to the inside edge of the foot, the knee will drop inwards and you will be guilty of that classic fault known as the "chicken leg". I have seen a surprising number of so-called taijiquan masters sporting some remarkable "chicken legs". What is more disturbing is to see a number of hand books and manuals written for the beginner with illustrations showing "chicken legs" in almost every posture. This is not a problem that's exclusive to taijiquan books written by westerners either, there are a surprising number of Chinese books showing "chicken legs".

Just remember that no one with such a fundamental fault can claim to be a master of the art. Correct foot posture is most challenged in one-legged postures like Golden Rooster stand on one leg and in very low posture such as Squatting Single Whip. Transitions from one posture to another that involve an inward adjustment of the foot can also cause a loss of good foot posture. For example, in the transition from Push to Single Whip the right foot has to make an adjustment that is greater than 90°. If you "pulled" the foot inward to make the adjustment the knee will drop inward and good foot posture will be lost. If you "pushed" the foot around in a slight "scooping" action with the outside edge of the foot, the transition will be stable, smooth and powerful, and leg alignment will be correct through the transition.

Another important aspect of good foot posture is to press all five toes slightly forward and down into the floor. It is very important that you do not "clutch" or "claw" inwards with the toes in order to grip the ground, because if you do so the sole of your foot will come off the ground and you will lose your root.

If you have badly collapsed arches and find it difficult to maintain good foot posture you may need to do some corrective exercise to strengthen the muscle in your lower legs and feet. One of the best in my experience is to roll your weight as far out as possible to the outside edge of your feet (balls of the feet well off the ground) and walk. Keep your knees relaxed and walk about 50 metres on soft ground or carpet, twice a day. Two weeks of this exercise every day should do it.

The other excellent exercise is the good old Horse Riding posture. It is interesting to note that one of the old names for this exercise was the "Foot Hold exercise". Don't stand too wide. Feet, shoulder width apart should be enough. Make sure that hip, knee and second toe alignment is correct and that you are "up on your arches". If you are standing correctly you should see the tips of the first two toes past the knee caps if you look down. If you cannot see your toes at all your weight is too far forward. Twenty minutes a day of correct standing for two weeks will do wonders for your foot posture. You might have to gradually build up to twenty minutes during the first week. You should also be aware of the fact that if you are hypoglycaemic (suffering from low blood sugar) - a very common problem today caused by a diet rich in carbohydrates with a high glycaemic index; sugar sweet drinks, chocolate, potatoes, white rice, white bread, cornflakes etc - you will have collapsed arches. For reasons not clearly understood by medical science, functional hypoglycaemia seems to cause chronic weakness in the muscles of the lower leg that support the arches. Therefore no amount of exercise will make a difference unless you correct your diet (Walther 1988).

If you do not suffer from collapsed arches (or if you do after you correct them) you must work diligently on developing "root". There is much more to "root" than the stability and "correctness" you achieve from the correct bio-mechanical use of the feet; but to discuss this would take us in to the areas of Yi and Qi or the use of the mind and energy. Since this is an article on the bio-mechanical aspects of the feet and knees I shall not discuss root in terms of Yi and Qi. However, I will leave you with a quotation from Master Cheng Man-Ching, which tells us almost everything we need to know about developing root.

"When you are in the midst of actively sitting or standing about and there is an opportunity to really pay attention, then use the sole of the foot to stick to the earth and imagine that it is sinking into the earth - after a long time imagine that the power of your foot is connected to the gravitational pull of the earth. If you can do this then the foot will possess root."