Comparison of Shotokan Karate Injuries against Injuries in other Martial Arts and Select NCAA Contact Sports

Authors: John-David Swanson, Jacquelynn Morrissey, Adam Barragan

Corresponding Author:
John-David Swanson, Ph.D.
Department of Biology and Biomedical Sciences,
Salve Regina University,
100 Ochre Point Ave,
Newport, RI 02840
jd.swanson@salve.edu
401-3413165

John-David Swanson is an Associate Professor and Interim Chair of the Department of Biology and Biomedical Sciences at Salve Regina University. A long time Shotokan Karate Practitioner he is the Director of both the National Collegiate Karate Association and the East Coast Collegiate Karate Union.

Comparison of Shotokan karate Injuries against Injuries in other Martial Arts and Select NCAA Contact Sports

ABSTRACT
United States Collegiate Shotokan karate clubs have historically played a vital role in the spread of the art of Shotokan karate. Additionally, Karate being included in the 2020 Olympics is expected to afford an increase in participation. In recent years, however, there has been an increase in risk management policies at universities to protect the liability of the school and increase the safety of the students who participate in any kind of athletic activity. While these policies are important, they vary depending on the type of sport or activity, resulting in different athletic activities being categorized into various categories based on their perceived risk. Shotokan karate is often placed into the high-risk category, with resulting policies being implemented in such a way as to make the day-to-day running of a Shotokan karate Club difficult to impossible. Interestingly, there is very little evidence that Shotokan karate is a high-risk sport and is deserving of the policies and regulations that it is often subjected to. To date, current risk assessments for injuries in Shotokan karate exist but have not been collated and organized in a meaningful way. To this end, using the current available data for injuries in Shotokan karate, this study aims to compare Shotokan karate to other types of martial arts and other collegiate sports, while looking at parameters including, but not limited to, the duration of training and number of days of training per week, to identify the safest ranges and determine ways to help prevent injury. It is hoped that in collating these data collegiate clubs will be able to help college policy makers to reach more informed decisions regarding risk management with respect to this sport.

Keywords: Karate, Tae Kwon do, Kung fu, Akido, Brazilian Jujitsu, Injury Rates, Policy, colleges, university, risk management

INTRODUCTION
United States Collegiate Shotokan karate clubs have historically played a vital role in the spread of the art, with many current practitioners beginning their training in this setting. In addition, Karate has been slated for inclusion in the 2020 Olympics so participation is expected to increase at all levels. However, in recent years there have been more stringent levels in risk management policies implemented at universities to protect both the liability of the school and safety of the students who participate in clubs and sports. This has been especially prevalent in public universities. While these policies are important, they vary depending on the type of sport or activity and result in different activities being grouped into categories based on their perceived risk. Risk managers often place Shotokan karate into the high-risk category based on their perception of what a martial art is with no understanding of the nature of Shotokan karate training. Thus, resulting policies are often implemented and make the day-to-day running of a Shotokan karate Club difficult to impossible. These policies vary from institution to institution but some examples include requirements to have two first aid certified people training on the floor at all times, otherwise practice is not allowed to proceed, only slow motion movements being allowed at all times, no contact allowed at anytime, including blocks, and very stringent travel policies for club members. Failure to adhere to any stipulated policies can result in the club loosing financial support from the university, loss of training space, or even removal of its charter from the university.

Interestingly, there is very little evidence that indicates Shotokan karate is a high-risk sport and deserving of the policies and regulations that it is often subjected to. Current risk assessments for injuries in Shotokan karate exist, but have not been collated and organized. Using the current available data for injuries in Shotokan karate, this study aims to compare Shotokan karate to other types of martial arts and common National Collegiate Athletic Association (NCAA) sports, while looking at parameters including, but not limited to, duration of training and number of days of training per week, to find the safest ranges and determine ways to help prevent injury. It is hoped that by collating these data collegiate club officers will be able to help policy makers reach more informed decisions regarding an appropriate level of risk management.

SAFETY AND RISK AT UNIVERSITIES
In United States collegiate athletics, each NCAA school is responsible for the well-being of their student-athletes [1]. These individuals are treated for any sports-related injury during training, practices, and games, with the institution affording the cost. Conversely, because collegiate Shotokan karate clubs receive little funding and are not subject to NCAA regulations, a school reserves the right to refuse to pay for medical care in the event of a club-related injury. Therefore, the university often imposes strict regulations to ensure the university cannot be held liable for any injuries sustained in the university sanctioned, but only partially supported sporting activity.

ADVANTAGES OF DOING KARATE
The first instance of Shotokan karate in the public was in the form of a demonstration to display the athletic advantages of the sport. The Japanese Ministry of Education held two exhibitions in coordination with Funakoshi Sensei to show how Karate is an excellent all-around exercise, enhancing agility and coordination [2]. Funakoshi saw the need to share the benefits of Shotokan with the public, and proceeded to do so through the Japanese university system where it is still prevalent today.

Shotokan has myriad physical and mental benefits. Physical benefits include improved balance, meaningful exercise, and the ability to protect oneself against a physical threat [2]. It is also a physical art, with flowing movements that support one’s connection to his/her movements. Karate training is beneficial to multi-sport athletes, as well. In a study done by Violan et al. (1997), karate practitioners showed increases in flexibility that may help decrease injury in other sports. Additionally, karate indirectly corrected body alignment through movements that supported basic body equilibrium. Increased strength in the upper extremities, hamstrings, and quads was also observed in karate practitioners [3].

Mental benefits include a sense of physiological well-being, the improved competitive nature of the participant, and, as an outlet treatment for troubled youth at risk for violence, can decrease hostility [4]. Karate also has the ability to facilitate improvements in concentration, respect, discipline, patience, and self-confidence [3].

Shotokan karate Training
Shotokan karate can be divided into three general areas that complement each other. Kihon, or fundamentals training, teaches the individual movements, techniques, and combinations of Shotokan training. Kata, or forms, are the heart of karate. Shotokan has traditionally had 26 kata that are used to transmit the art. They contain active combinations of almost every technique used and can be extensively interpreted into different fighting methodologies through the study of Bunkai or the application of kata. Kumite, or partner training, is the actual application of these techniques and combinations to another human being. Interestingly, Shotokan participants spend roughly one third of their time studying Kihon, Kata and Kumite, respectively, though this ratio can change slightly depending on the participants rank and needs at the time.

Of the three areas of training, the one with the most potential risk is Kumite. However, Shotokan karate is unique in the systematic nature by which Kumite is introduced to students. Normally it is introduced only in a basic form through to the mid colored belt ranks, representing the first one to two years of training. These forms of kumite have very strict rules governing distance and techniques used, and remove any randomness that could result in injury if a mistake is made. By the time the student has completed this apprenticeship, they understand elements of distance, how to block, punch, strike, and kick, as well as how to move backwards and forwards and understand angles. After the mid colored belt ranks they are eased into slightly more random situations and distancing is varied. They are also often allowed to do slow motion free sparring for the first time. By using this approach, the student is comfortable with their body and that of their partner, and can move with confidence, knowing and understanding how to do so properly. Students are only allowed to take part in fast, tournament-style sparring above the brown belt level, normally achieved in their third to fourth year of training. It is not until second-degree black belt (representing 5-6 years of training) that free sparring is required for testing. Many if not most other martial arts do not go through this process and begin immediately teaching free sparring from the first day of training.

INJURY RATES
Injury Rates in Shotokan karate
Of the three aspects of training, university risk management assessors’ focus on the kumite portion. Interestingly, assessors are often unaware that kumite only comprises approximately one third of the training time and of that, a much smaller proportion (at most 5%) of both time and the total population of participants in a club is devoted to free sparring, where most injuries occur.

There have been a relatively large number of studies related to injuries in Shotokan karate [5-12]. However, many of these studies are focused on tournament (regional, national and international) competition or youth injuries. Therefore, somewhat surprisingly, there is very little accounting for injuries that are sustained in regular club training in family or collegiate clubs.

By examining the available studies, data was reported in two ways, allowing for representation by two metrics. The first is an injury rate per bout and measures the chance that a competitor will sustain an injury in a single karate match. From the data examined, it was seen that the rate was as high as 31.4% [5] and as low as 9% [6]. The average across the seven studies examined was 20.5% (std. error 3.42%), thereby approximating a one in five chance of sustaining an injury in a tournament match (Table 1). The second rate was a general percentage of injury per person. This could be generalized to the general injury rate in Shotokan karate. The highest rate reported was 30% [12] and the lowest was 18.3% [8]. When averaged, the four studies indicated an injury rate of 23.6% (std. error 2.85%) or almost a one in four chance of receiving an injury during training over an unspecified period of time (Table 1).

Table 1

It is important to note that these data could be under or over estimations of the actual injury rate. This could be due to several factors, including 1) almost all data was collected in individuals training and competing (many at very high levels), resulting in an over estimation of the injury rate for populations that do not compete; and 2) many injuries are not reported, or not deemed as needing attention by the practitioner, resulting in a possible underestimation of the injury rate. This is exemplified in a study by De Souza et al. (2011) who looked at the nature and rate of injuries in training in both Karate and Jujitsu. This study, where all injuries (from very minor to severe) were recorded, resulted in a much higher rate of 88.6% being reported. In addition, a second study done by Birrer and Birrer (1983) reported that of 79 observed tournament injuries only 37% were reported initially and only 50% were reported in a subsequent interview. Therefore, while not perfect, the data that is currently available do suggest an injury rate in people training at a high level for and in tournament competition, and reported severe injuries is approximately 23% (Table 1).

Table 2

Birrer and Birrer (1984), De Sousa et al. (2011), and Pieter (2005), among others, have also been among several studies that have identified the nature of reported injures in Shotokan karate. The most common five injuries include the common bump and bruise (contusions) (46.9% of all injuries), epistaxis or bleeding nose (19.9%), lacerations or cuts (14.4%), sprains/strains (3.35%), and concussions (2%). De Sousa et al. (2011) also reported the location of these injuries and it was found that most are sustained in the hands and fingers (15.5%), feet/toes (12.8%), leg (9.5%), mouth and teeth (8.8%), nose (6.8%), knee (6.8%), and skull (6.1%). While it must be remembered that these injuries were sustained for the most part during tournaments and training for tournaments, the data provide a good snapshot and can be extrapolated to daily training.

In order to confirm these data, there is a need for more injury rates recorded and published in both family-run and collegiate clubs. Swanson’s anecdotal evidence from his own collegiate run clubs in the USA indicate that the injury rate in general training is very low. During his 20 years of being a head instructor to over 1000 students, only three university incident forms were filled out during normal training (one for a broken finger, and two from students fainting from low sugar levels).

How does Shotokan karate compare?
Fortunately, there have been several studies that have either reported or directly compared Shotokan injury rates to other martial arts including Tae Kwon do, Aikido, Kung Fu, Judo, Tai Chi and Jujitsu (Table 3). From these data the most injury-prone arts appear to be Jujitsu (97.5%), Aikido (51%), and Kung Fu (38%), followed by Judo, Karate, and Tae Kwon Do (19.5%, 23.5%, 22% respectively). The least injury prone martial art of those studied is Tai Chi (14%).

Table 3

From these data, it is important to point out several things. First, the Jujitsu study is the same study that reported every injury in Shotokan above, hence why this value is high. However, an outcome of this study did infer that Shotokan karate does indeed have a lower injury rate than Jujitsu. Second, Jujitsu and Aikido injury rates differed significantly from Judo. One potential explanation is that Judo adheres to a very specific set of competition rules that are presumably geared towards injury prevention. Third, it is interesting to note that Karate, Judo, and Tae Kwon do have very similar injury rates. Again this could be indicative of 1) the competition aspects of these martial arts and 2) Tae Kwon do and Karate having a shared lineage. Fourth, Tai Chi was the least injury-prone martial art and is practiced in slow motion. Therefore, Tae Chi could be considered a base line of injury for all martial arts and movement in general. In any case, from the data above it is safe to imply that Shotokan karate is certainly one of the less injury-prone martial arts.

In comparing the nature of injuries across the martial arts they seem to fall into two major groups depending on their nature. Karate, Tae Kwon Do, Kung Fu, (and to a lesser extent) Tai Chi, are all striking arts and therefore seem to have had similar injuries to Karate (Table 3). Judo, Jujitsu, and Aikido are locking and throwing arts and differ in that the majority of their injuries occur in the knees, shoulders, ears, ankles, and hand/fingers [13] and are primarily contusions (56%), sprains (12%) and abrasions (8%) [14].

Comparisons to other sports
Our Shotokan karate injury rate can be compared to a 16-year NCAA injury study where multiple sports in both practice and competition were tracked for their injuries [15] (Table 4). When compared, the only sport with a greater injury rate is football, with the remainder of the sports having a lower rate than Shotokan karate [15]. In looking at this comparison, it is important to remember that in most NCAA sports the time of one athlete exposure is far greater than one athlete exposure in Shotokan karate competition, though a training duration would be similar to the NCAA contact sports.

Table 4

It is worth noting that it is likely that the published injury rates are lower than what are actually reported. For example, ice hockey injuries are far less prevalent in this study than the study done by Zetaruk [16]. A possible reason for this is that the college athlete often does not report an injury unless it affects his/her play, therefore many injuries are potentially unreported for fear that the athlete will be taken out of a game or season. Interestingly, the same could be said for Shotokan karate, where Birrer and Birrer (1983) noted that many Karate injuries also go unreported. According to a study done by Kujala et al. in 1995, the majority of injuries in an analysis of sports injury insurance occurred in athletes ages 20-24, which is not congruent with the data from the NCAA study Zetaruk 2000 study, supporting the hypothesis that NCAA injuries often go underreported [17]. Interestingly, the Kujala et al. (1995) study showed that injury rates are almost identical across Soccer (25.4%), Ice Hockey (26%), Volleyball (21.5%), Judo (21.3%), and Karate (24.7%) among athletes between the ages of 20-24, with significant decreases in injury rates immediately below and above these ages (Figure 1). In particular, when compared to other sports, Karate continues to maintain its relative injury rate while other sports such as Soccer, Ice Hockey and Judo drop very significantly. This observation could be due to Karate continuing to be practiced at a high level to a much later stage in life compared to these other sports (Figure 1). In any event it is important to be able to infer from these data that Shotokan karate does not seem any more dangerous than these other collegiate sports.

Figure 1: Injury rates over various sports broken out by age of participant (adapted from Kujala et al 1995).
Firgure 1

RISK FACTORS IN SHOTOKAN KARATE
Risk Factors
According to Pieter (2005) and Zetaruk et al. 2000 the major risk factors for injury in Shotokan karate and the Martial Arts in general are the time spent in training, age of the participant, and the experience of the participant. Specifically, it was found that overtraining, and older and inexperienced participants presented the highest risk of injury. In addition, some of these risk factors are multiplicative when combined (i.e. when a participant is both older and inexperienced). The impact of age on injury risk was particularly striking in a study by Kujala et al (1995), where it was shown that while other injury rates seemed to drop off in other sports past the age of 35, Karate seemed to maintain (Figure 1).

The Instructor
The single most important factor in preventing injury is the education and experience level of the instructor [14]. This indicates the requirement of having a strong organizational “apprenticeship” or instructor qualification that includes specific instruction in warm up and cool down procedures, injury prevention and the mechanisms of prevention, the ability to determine overtraining, the ability to give appropriate advice to students in the implication of techniques in both execution and results of delivery (i.e. Mawashi geri or turning kick to the head), methods to observe the group and determine if partner training is becoming dangerous, and finally, instruction in how to develop the ability to determine different body types and aid the student to move within his/her body type. These skills take years to develop, but having a qualified, experienced instructor cannot be understated.

Tournaments
This theme also applies to tournament referees, who should have previous competition experience themselves, as well sufficient instruction and practice in controlling the combatants. The most effective method for an organization to control this is through rigorous and regular licensing.

Keeping in mind that there is a difference between incidences seen in training versus competition, injury is more commonly seen in competition than in training due to the increased probability of contact. This includes, but is not limited to, punches, kicks, and blocks [2, 8]. Therefore, additional policies need to be considered to keep participants safe. The first recommendation is reducing or eliminating the overall contact during tournament combat, and the enforcement of scoring by correct technique of strike and control of punches and kicks without any injury to opponent. In doing this, form and function will predominate and the karate practitioner will win points for their knowledge and training [8]. Furthermore, tournament competition can be made safer by increased enforcement of rules by referees. Success in this are has been demonstrated by new World Karate Federation (WKF) rules that have lowered the risk of injury by half [5, 18]. The continued refinement of rules through video analysis would also aid in seeing where and when rule changes need to be made, and would make visible regions of the body that may need extra attention, such as with stretching or rehabilitation [19].

In addition, the WKF requires a mouth guard, head, hand and wrist protection, which must be worn during any tournament and has a direct impact in lowering the number of injuries during tournaments [4, 20].

WHAT CAN THE PARTICIPANT DO?
While many injuries can be avoided by having a qualified and experienced instructor and an organization with sound policies in place for competition, there are several steps that an individual practitioner can take to lower their own injury risk. It is well known that certain measures, such as those described by the popular website livestrong.com, decrease participant injury rates and can be summarized as folows: warm up, strengthening the muscles and joints, stretch, and polish their technique.

Warm up
The warm up is often misinterpreted. It should consist of light movement to get the blood flowing and the muscles warm and loose [21]. The nature of the movement should be similar in nature to what the practitioner will undergo in regular training (such as slow movement kata, or kihon). The warm up is not a workout and the correct level of warmth was best described by Bruce Lee in the Tao of Jeet Kune Do as being “movement such as there is a light sheen of sweat on the forehead” [22]. It should take place for at least 10-15 minutes before training begins and can contain some light active stretching.

Strengthen the muscles and joints
It is also important to do some degree of supplemental training in the athlete’s own time. This will ensure that the body, especially the muscles surrounding the joints, has the strength to be able to hold together the joints during the fast explosive movements that karate requires. It is important that the practitioner also work their core to prevent back injury and develop the ability to keep a strong center when training. This can take the form of tradition dumbbell or barbell training, or simple pull up, push-ups or sit up work. Some of this work on an unstable surface, such as one leg or incorporation of a Swedish ball, can also greatly benefit the practitioner as it increases proprioception. Once again, balanced exercises that are similar in nature to the intended sport are recommended.

Stretch
Stretching and flexibility are very important in injury prevention. Stretching helps prevent pulling and straining of the muscle and allows greater range of movement through the lengthening of the muscle and other tissues, as well as relaxing of the proprioceptors. Light stretching during the warm up is important, but it is not advised to stretch to increase overall flexibility until the end of the training session or supplementary workout, when the muscles are at their warmest. Personally, we have found that Vinyasana type Yoga stretches superior in preparing the karate practitioner for a workout. It is important, once again, to stretch in accordance to the sport that one is performing, and it is important to stretch carefully. For a great reference on stretching in general, we recommend “Ultimate Flexibility: A complete Guide for Stretching for Martial Arts” by Sang H. Kim [23].

Polish their technique
This last mantra for training to avoid injury relates to continued diligence in learning karate and having the athlete listen to their body as they learn. A prerequisite is that the athlete listens to their instructor and follows their advice. A perfect example of this is in having too much lateral movement in the knee, a hinge joint that only moves backward and forward, not laterally. Therefore, when standing in forward stance it is imperative to listen to your instructor when they tell you that your knee is positioned too far inward or outward. Even an angle of 5o can put undue strain on the joint and over a very short period of time lead to knee injuries that can debilitate the practitioner [24]. An experienced instructor understands the nature of the movement in the knee and it is their job to inform the student if the bend is incorrect. However, it is then up to the practitioner to make the change. Karate has been developed in accordance with the principles of biomechanics and if performed correctly will lead to few, if any, injuries.

The second concept is for the athlete to be aware of your body. If they find their body is starting to ache (especially joint pain), they need to bring it up with their physician and/or their instructor. Chances are that the athlete has incorrect movement for their body’s make up and need modifications. In addition, if an instructor is being unreasonable in their demands and the practitioner feels it may lead to injury, they need to assess the club and training that they are receiving. As an instructor of several university courses in Karate at the Pennsylvania State University, we were instructed to go by the mantra “what would a reasonably prudent person do?” The instructor should always take this into account for each student and adjust accordingly.

The final concept is that of over training. It has been recommended that for most people 3-5 hours of Karate practice per week is sufficient, [16] however, at times where extra training is required (tournament or examination practice) extra time may be employed. Symptoms of overtraining include an increase in muscle aches and strains, trouble sleeping, and eventually a breakdown of the immune system [21]. It is important for the practitioner to pay attention to these types of symptoms as the increase in injury rate climbs significantly.

CONCLUSIONS
From the above evidence, it is clear that Shotokan karate is a fairly safe sport with injury rates of practitioners engaged in high-level competitions averaging 23%. Most of these injuries were reported as contusions due to the striking nature of the art. This percentage showed that Shotokan karate is one of the safer martial arts with Tai Chi a slow moving individually practiced martial art presenting an injury rate of 14%. When compared to other NCAA sports Shotokan karate did not seem to pose any additional risk. Major risk factors were identified to be overtraining, older and inexperienced participants, the quality of the instructor, and tournament training. Finally, it was clear that by following several steps an individual practitioner lower their own injury risk. In particular key areas included sufficient warm up, strengthening the muscles and joints, stretch, and constantly polishing and correcting technique.

APPLICATIONS IN SPORT
The data presented here is a survey of Shotokan karate related injuries in an effort to quantify actual versus perceived injury rates. These rates are also compared to other martial arts as well as other NCAA sports. These findings are imperative to help guide university administrators and university risk management policy makers to prevent incorrectly categorizing Shotokan Karate practice into high-risk groups who are often subjected to debilitating polices that prevent meaningful practice of Shotokan karate on college campuses. This is particularly relevant since the number of participants of collegiate karate is expected to rise with the inclusion of Karate in the 2020 Olympic Games.

ACKNOWLEDGMENTS
None

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