Injury free practice
The practice of Karate provides many benefits to your physiological well being. It is one of the more physically intense martial arts demanding aerobic fitness, stamina, core strength, flexibility and agility. And yet, there are karate-ka who have over time developed physical ailments which they possibly may not have ended up with had they not practiced karate.
It is crutial to learn from as early on in your karate journey as possible to practice "good" karate, rather than "bad" karate that may cause injury over the long term.
The Collapsing Knee
The most common ailment that afflicts long term training karate-ka is knee joint degeneration, sometimes requiring knee replacement surgery in severe cases. However whether you practice karate or not, knee pain is a very common problem affecting 1-in-4 adults. It is the second most common cause of long-term pain (after back pain) and the number of operations carried out each year for knee problems is steadily rising. Certain conditions like osteoarthritis due to wear and tear of the knee joint or an injured joint too can cause instability of the knee. The weakened muscles or ligaments, unstable kneecap can also play a role in reduced stability, which can make the knee feel buckled during certain movements. Other conditions in which trauma or degeneration lead to bony fragments, broken spurs or loose bodies to float in the knee joint can cause feeling of knee buckling during knee movements. Sometimes calcium can get built up in knee tissues causing inflammation in a condition called chondrocalcinosis. While some types of arthritis can cause knee buckling; oversensitive joint and tissues too can lead to a feeling of 'Knee giving way' or Knee Buckling.
What needs to be highlighted for karate-ka is that joint damage can be exacerbated by incorrect or exaggerated stances where your knee is forced to bend the wrong way. Continually training in this manner will result in a collapsed knee.
The reason your knee collapses is generally due to a biomechanical compromise; i.e. low degree of mobility in the hips or inadequate ankle flexibility. It can also be because you are too stiff and lack quad length or hamstring sufficiency. Your knee basically buckles in to unload your weight and buy slack. Although this might not seem like a big problem today – one day it will.
Even if you are young and strong, a few years of training with a collapsed knee will eventually lead to an accumulation of micro tears in your knee joint until eventually, it will give. This pain may prompt you to visit a physiotherapist and 9 times out of 10, the physio will give you a program of “corrective exercises” to do, which may involve weights, resistance bands and/or balance boards.
The key is to always make sure your stances and stance transitions are performed correctly.
By making sure your knee tracks over your foot. This is the easiest method for an anatomically stable, powerful and safe stance.
A good verbal cue for instructors to use is: “Track your foot with your knee”. The reason is two fold. Firstly your ankle has only a little range of motion in the sideways plane.
If your knee always collapses inside your foot, you are in danger. Also you should not over-compensate and push the knee outside the line of your foot either as that will be just as bad.
Take a look at the pictures above comparing incorrect/correct zenkutsu-dachi, shiko-dachi, kiba-dachi & neko-ashi-dachi.
Zenkutsu-dachi is the most frequently used stance in Shotokan karate, so its definitely worth getting this stance as biomechanically correct as possible. Work on pointing the back foot forward as much as your flexibility allows, this means you should not go too long in the stance as that will force the foot to point outward as it struggles beyond the limit of its range of motion. Do not go too wide in the stance, sometimes seen in advanced students as they get away from the beginner habit of going too narrow and off balance. Keep the stance between hip and shoulder width wide, never more than this, otherwise you will find yourself twisting your back knee inwards when performing shomen (front facing) techniques like gyaku-zuki and placing dangerous torque on the knee as you try and keep the heel in contact with the floor. You should try to keep the front of your thigh and knee-cap pointing in the same direction as the big toe of your foot and twist at the hip.
See below for explanations regarding knee joint safety by masters Scott Langley Sensei and Rick Hotton Sensei.
You should pay attention to your knee and joint health in all aspects of karate training whether it be stretching, warm-up exercises, kihon, kata or kumite, as you should during the rest of your everyday life. There are 'old school' sensei out there who possess great skill and and are good instructors, but may on occasion use outdated training methods that could be unhealthy for your joints over the long term. Use your common sense.
Here are two examples of lunge attacks in kumite (sparring). The position in the picture on the left is seen all too often. Look at the direction of the back leg knee bend and that of the foot pointing almost perpendicular. This is placing dangerous amount of rotational stress on the knee joint. Do this enough times and your knee will suffer the consequences.
The picture on the right shows the safe way to place your back foot if lunging in for a deep attack. There are karate-ka who try to stay overly rooted keeping the back heel connected with the floor for gyaku-zuki, however that is often not practical when attacking fast with yori-ashi. Different circumstances call for different methods and techniques.
Another cause of joint damage in the knees and also the elbows is hyperextension.
A lot of karate training involves punching or kicking into the the air. What you must bear in mind is that if you punch or kick full force into the air without anything to stop the motion, you can end up hyperextending your arm or leg. That is, your lower arm of leg locks out at the elbow or knee and continues past its natural range of motion. Knee hyperextension injuries can vary from a mild strain to a severe tendon injury. Recovery from a mild to moderate sprain following a knee hyperextension injury can take 2 to 4 weeks. Surgical reconstruction of an injured ligament often leads to full recovery but often brings with it a long recovery time of 6 months or more.
You should consciously ensure your elbow is slightly bent when your punch reaches the end of its extension. You can still throw pretty hard but your ligaments will be protected since you won't lock your elbow out. For those working on maximum power techniques, it would be advisable to reign it in to not more than about 80% max for in-air practice and only go higher for impact training using pad protection.
You should remember that in reality, your punches, kicks and other techniques are meant to be striking through the target and thereby impacting prior to full extension of your limbs, i.e. real karate punches should not be finishing with fully extended arms at the point of surface impact with the target. We train the full motion of techniques in kihon and kumite exercises, but at the same time should be keeping in mind that these are training aids and must use them with the aforementioned care.