Studying Kendo Science (lenghty read!!)

[mingshi]

Think Kendo is safe? Think again. Just cannot imagine how many people have been doing in-depth scientific research on Kendo over the last 100 years. I "accidentally" came across the National Library Medicine and come across the following articles:-

Strenuous exercise-induced change in redox state of human serum albumin during intensive kendo training.

Imai H, Hayashi T, Negawa T, Nakamura K, Tomida M, Koda K, Tajima T, Koda Y, Suda K, Era S.

Department of Health and Physical Education, Faculty of Education, Gifu University, Japan.

A high-performance liquid chromatographic (HPLC) analysis of human serum albumin (HSA) using an ion-exchange (DEAE-form) column shows three components: The principal component corresponds to human mercaptalbumin (HMA); the secondary to nonmercaptalbumin (HNA), having mixed disulfide with cystine (HNA[Cys]), or oxidized glutathione (HNA[Glut]); and the tertiary to HNA, oxidized more highly than mixed disulfide. The purpose of the present study is to clarify the effects of strenuous exercise load on HMA--><--HNA conversion (i.e., dynamic change in redox state) of HSA from elite kendo athletes (n=30; 20.0+/-1.1 years old). They participated in an intensive kendo training camp for 5 d. The mean value for the HMA fraction (f[HMA]) of kendo athletes after camp (62.8+/-2.4%) was significantly lower than before camp (71.9+/-3.7%) (p<0.0005). In contrast, the mean value for f(HNA-1) (i.e., f[HNA(Cys) and HNA(Glut)]) after camp (34.2+/-2.1%) was significantly higher than before camp (25.7+/-3.7%) (p<0.0005). These results suggested that strenuous physical exercise markedly increased the oxidized albumin level in extracellular fluids during the intensive training camp.

Stress fracture of the ulnar styloid process in kendo player--a case report.

Itadera E, Ichikawa N, Hashizume H, Inoue H.

Department of Orthopedic Surgery, Kochi Prefectural Aki Hospital, Kochi, Japan. itadera@ppp.bekkoame.ne.jp

We present a case report of a 15-year-old kendo (Japanese fencing) player who suffered a stress fracture of the ulnar styloid process. Exercise of the kendo requires the athlete to flex his non-dominant wrist repeatedly in an ulnar direction, and causes the disorder. Excision of the osteochondral fragment relieved the symptoms. This lesion is likely to occur with other sports or activities which demand similar motion of the wrists.

Coactivation of the flexor muscles as a synergist with the extensors during ballistic finger extension movement in trained kendo and karate athletes.

Lee JB, Matsumoto T, Othman T, Yamauchi M, Taimura A, Kaneda E, Ohwatari N, Kosaka M.

Department of Environmental Physiology, Institute of Tropical Medicine, Nagasaki University, Japan.

To analyse the effects of ballistic property training on ballistic finger extension movement, surface electromyographic pattern (EMGs) of the finger extensor and flexor muscles and the acceleration signal of the middle finger were recorded in trained kendo and karate athletes, and sedentary non-athletic men. Ballistic finger extension did not show the characteristic triphasic EMG pattern reported in single joint, but a coactivation of flexor and extensor muscles. Reaction time (RT) in kendo (143 +/- 12 msec) and karate (146 +/- 11 msec) athletes were significantly shorter than that in the control (176 +/- 12 msec). The shortenings of the RT were attributed to both the shortenings of premotor time and motor time. The delay of the flexor muscles discharge after those of the extensors in kendo (0.8 +/- 7.0 msec) and karate (-0.2 +/- 5.0 msec) athletes was significantly shorter than in control (12.7 +/-5.6 msec). These results suggest that the RT is shortened through motor learning in the kendo and karate athletes who trained for momentary movements; and that the flexor muscles may play an important role as a synergist in heightening the efficiency of ballistic finger extension in coordination with the extensor muscles.

Bilateral stress fractures of the ulnae in a Kendo (Japanese fencing) player.

Sujino T, Ohe T, Shinozuka M.

Department of Orthopaedic Surgery, Natogaya Hospital, Kashiwa-shi, Japan.

A case of bilateral stress fractures of the ulnae in a Kendo (Japanese fencing) player is reported; the mechanism of the fractures, particularly the difference in the site of fracture between the right and left ulna, is discussed.

Repetitive strain injury to the foot in elite women kendoka.

Nunn NR, Dyas JW, Dodd IP.

Cheltenham and Gloucester College of Higher Education, United Kingdom.

OBJECTIVE: To account for the apparent high incidence of pain in the feet of elite women kendo players. METHODS: A clinical evaluation was done by a chiropractor, the women were interviewed about their kendo experience, and the conditions and frequency of training and ground reaction forces were measured on a Kistler force plate during the kendo attacking action. RESULTS: Four out the five women presented with plantar fasciitis. They had all practised for some time on wooden floors laid on concrete, for between two to four hours a week. They warmed up conscientiously but cool down was more cursory. The force plate results showed that they were hitting the floor with a mean force of four times body weight during a transient impact. CONCLUSIONS: High motivation for practice and training, hard floors, ignoring painful feet, and cursory postpractice cool down probably produced the condition. Postpractice icing and stretching were found to be most effective in the short term. In the longer term reducing the level of impact, either by training on sprung floors or changing the footwork, might reduce the incidence and intensity of the fasciitis.

A case of pneumomediastinum caused by closed tracheal injury during the game of Kendo (Japanese fencing)

Article in Japanese

Komatsu H, Enzan K, Mitsuhata H, Hasegawa J, Matsumoto S, Suzuki M, Nishihira S.

Department of Anesthesiology, Akita University Hospital.

A patient was injured accidentally on his neck during the game of Kendo (Japanese fencing). After his neck injury, he continued to play Kendo because there was no symptom at that time. Starting 10 minutes after the injury, swelling as well as pain on the neck and dyspnea developed gradually. After the admission to the emergency room, computed tomography revealed pneumomediastinum. Nasal endotracheal intubation was performed gently under fiberscopy. Dyspnea and pneumomediastinum improved gradually during the 6 days after the admission. A patient who has received a closed injury on his neck without immediate symptoms or signs must be observed closely because the absence of symptoms or signs does not guarantee the absence of the injury of the trachea.

An unusual cause of metatarsal pain in a young kendo player.

Sakamoto K, Mizuta H, Okajima K, Kitagawa T.

Department of Orthopaedic Surgery, Kumamoto University Medical School, Japan.

A female case of march hemoglobinuria induced by kendo (Japanese fencing) exercise

(Article in Japanese)

Urabe M, Hara Y, Hokama A, Suzuki M, Wakabayashi T, Ishii J.

March hemoglobinuria caused by Kendo: report on 3 cases with exertion test of Kendo and study on erythrocyte membrane SDS-PAGE

(Article in Japanese)

Asai T, Itoh K, Oh H, Sugiura Y, Endo N, Nakamura H, Yoshida S, Igarashi T, Fujioka S.

Carotid dissecting aneurysm due to blunt (rubbing) injury of the Kendo protector

Article in Japanese

Sakai H, Kaneko D, Yuki K, Nakamura N.

A case of dissecting aneurysm of the cervical internal carotid artery due to rare mechanism by non-penetrating injury is described. A 45-year-old right-handed man had complaints of the right lateral neck pain during exercise of KENDO wearing a tight headneck protector. Following sudden dysarthria and left hemiplegia, he developed loss of consciousness and generalized convulsion. Five hours after admission, he became alert and had no neurological deficits. Four days after these episodes, he loss visual acuity of the right eye, and a few days later he showed left hemiplegia, hypotension, hypersomnia and right-sides Horner's syndrome. Right retrograde brachial angiography revealed so-called "string sign" in the right extracranial internal carotid artery and delayed circulation in the right cerebral hemisphere. He was diagnosed as having traumatic dissecting aneurysm due to blunt (rubbing) injury. He was treated with STA-MCA anastomosis 3 weeks after the accident. Usually, carotid dissecting aneurysm due to blunt injury is produced by hyperextension and contralateral rotation of the neck or direct blow to the neck, but our case shows a possible mechanism of rubbing injury such as simple anteroposterior flexion under tight neck fixation.

[A case of march hemoglobinuria following "kendo" (Japanese fencing) exercise

Article in Japanese

Mineoka K, Yamamoto K, Isemura T, Fujii H, Wada S, Masaki K.

[On the influence of Kendo training or home study upon uropepsin excretion

Article in Japanese

Kitamura R.

Source:
National Center for Biotechnology Information

Just interesting to know what they are all doing in Education Universities when they are not having Kendo sessions.

[alexpollijr]

Err.. well, you might actually be right.
But, every sport has it's share of trauma. See football for instance.

PS> That case about the missed tsuki is downright scary!

[JSchmidt]

"Think Kendo is safe? Think again. "

Crap..ok, I quit!

[munenmuso]

I thought those drug generic names were enough tongue twisters but after reading that lengthy post by Mingshi I decided to do more kendo and avoid reading more science/medical journal. Reading it alone is already hazardous to your health. Did you get that from the Tales From the Crypts. Scary stuff.....

[nodachi]

Ya know... if you research any sport enough, it will be found to be unsafe... granted some are less safe than others, but there is a danger to everything...

I think the moral of the story is to listen to your body so you can prevent and fix injuries early on. Also, for those nasty injuries that could have been prevented if ones kendo was stronger to prevent the opponent from hurting you in the first place, I think that just gives all the more reason to train harder to prevent such injuries by making ones kendo stronger. Must train. Sorry that sounds redundant, sleepy... zzzzzzzz...


Although, does anyone have any info on signs of injuries that denote worse things that need to be checked into immediately and may require sitting out to make sure one is okay like that whole neck injury thingy above? If I felt okay I would probably continue to compete, but after reading that I might think otherwise down the road. More info on such dangerous things to look out for would be both education, interesting, and appreciated.

[Stan]

I thought the fact that my opponent (in kendo) was standing in front of me with a 4ft stick ready and willing to hit me with said 4ft stick was proof enough that kendo was dangerous...I guess I was wrong.

[Neil Gendzwill]

"march hemoglobinuria" means blood in the urine, IIRC. A very common thing to occur in old-school hard-core high school or college practice.

[Old Warrior]

"I think the moral of the story is to listen to your body"

"Hello Body, this is me. How am I doing?"

"Have you considered miniature golf?"

"Shut-up, what do you know!!!"

[Raiza]

Any physical activity is not without some level of risk, so it's not surprising that a few case reports have come up, which are what most of the publications that mingshi mentioned. I would recommend, mingshi, that you might want to consult someone with a scientific/medical background (i.e. someone with at least a science/medical degree) before you cut and paste a PubMed search result on a big global forum where not everyone has a scientific/medical background. Some of the abstracts shown are easy to follow, while others would make one's head spin! I think the best approach for someone citing a PubMed result or any other scientific article is that they be able to translate it into everyday language, as best they can, or ask someone who can. My feeble attempt at this is outlined on the second page of the "women and do" thread. One day I will figure out how to put a link to that...

The article by Lee doesn't address an injury or ill-effect at all but an increased speed in muscle responses of kendoka and karateka! My muscles will work faster over time, whee!

Regarding march hemaglobinuria (hemaglobin in the urine)...
March hemaglobinuria is when the inner contents of crushed red blood cells (i.e. for kendo: frequent bruising, high-impact footwork) are excreted by the kidneys into the urine. Hemaglobin, the protein responsible for binding oxygen for delivery throughout the body and also responsible for red blood cells being red (hemaglobin has iron attached to it too), winds up in the urine along with all the other stuff that was inside the squashed red blood cells. Old-school and prefectural riot-squad kendoka are more likely to encounter this at a noticeable level than others, but no one is immune. For avid kendoka, if your diet is fine and you feel sluggish for no other apparent reason, this may be the reason why so bring it up with your doctor if your lack of energy is serious enough to warrant medical attention, as most doctors outside of Japan and Korea have little idea what kendo/kumdo is. This kind of hemaglobinuria is certainly not a kendo-specific injury, as the condition was named after soldiers developing anemia after prolonged marching! Same goes for the metatarsal (metatarsals are the long bones in the foot) injury referred to by Sakamoto, which is also known as a march fracture, which I've had the pleasure of having. Not fun!

Anyhow, train hard and respect both yourself and your opponent.

[Paburo]

Originally posted by Raiza
Regarding march hemaglobinuria (hemaglobin in the urine)...
March hemaglobinuria is when the inner contents of crushed red blood cells (i.e. for kendo: frequent bruising, high-impact footwork) are excreted by the kidneys into the urine

i thought at first it had to do something with tamago uchi/tsuki

[aru-ma]

like what alexpollijr said, I think most of us know that when doing a sport/martial arts we will receive injuries or some form of trauma. Personally I think those researchs are usefull as those research are in informing us of the specific risk of doing kendo while on the other hand it's a bit like saying thinking/work will cause a certain amount of stress, and I havent seen a research that says " the increase in tax is directly proportionate to the increase in stress in low to middle incomehouse hold with 2 children or more".

[titus]

This actually brings up a good point I've been thinking about. Does anyone actually train on a sprung floor? Also, how can you tell if it's sprung or not?

The only sprung floor I know of is at a famous club downtown, the dancefloor is sprung and you can dance all night without feeling tired or sore later. However, it looks like a regular wooden floor and feels the same if you jump up and down initially, you have to do intensive work on it for a long time and "feel" the difference later.

Any ideas?

[Neil Gendzwill]

You can usually tell right away if a floor is sprung or not, just do a few fumikomi on it and you can feel whether it has any spring.

[titus]

Hi Neil,

Do you train on a sprung floor yourself? Are there any in Saskatoon? Just curious. I'm just wondering how common it is.

[kendomushi]

Practicing on the military base here, we use a racquetball court, its a decent floor, but not sprung at all.
The dojo I go to out in real Japan (as opposed to the little america of the military base) is made up of large planks set in a wooden frame. The planks are not nailed or fixed in place by anything more than the frame they sit in. The frame is then supported by what look like great big old leaf springs from 1940s truck suspensions. The floor really springs when you do fumikomi. The for an added bit of atmosphere, under the floor are several large clay pots, when you do fumikomi and the air rushes in and out of these, it makes for a very interesting rumble or roaring sound.