[sumo] Question somewhat related to death of rikishi - medical
studies of sumo wrestlers
Chuck Finberg
cfinberg862 at yahoo.com
Sat Jul 7 16:12:13 EDT 2007
With respect, Doreen, I disagree that a statistically significant study cannot be done regarding health issues among sumotori. Although I am not an epidemiologist or biostatistician, it is certainly within their capabilities to perform meaningful comparisons using smaller populations, and some conclusions can be reached within acceptable confidence intervals. The confidence which can be placed in results of studies which associate physical consequences with certain activities may depend upon the relative frequencies of the condition.
Following are a few examples of medical studies which have been published regarding sumo. Among them you will find an abstract which opines that sumotori with lower BMI have longer survival rates. Another finds fairly high relative incidence of gout, diabetes and hypertension. And one, which I doubt has significance to the death of Tokitaizan, does observe that certain diastolic readings above normal in sumotori "may ... represent an extreme example of the physiologic adaptation of the athlete's heart." (All of these abstracts may be located by search at www.pubmed.com):
Ann Hum Biol. 1999 Mar-Apr;26(2):179-84.
Hierarchical differences in body composition of professional Sumo wrestlers.
Hattori K, Kondo M, Abe T, Tanaka S, Fukunaga T.
Department of Health and Physical Education, Ibaraki University, Mito, Japan.
hattori at mito.ipc.ibaraki.ac.jp
The body composition of 36 professional Sumo wrestlers and 39 collegiate male
students were assessed densitometrically. The means of body weight, BMI and %fat
for Sumo wrestlers were 117.1 kg, 36.5 and 26.2%, extraordinarily large compared
with untrained men (p < 0.001). Results of the analysis of variance of divisions
of Sumo wrestlers revealed significant differences in body weight, fat-free mass,
fat mass, BMI, fat-free mass index (FFM/height2) and fat mass index (FM/height2).
For the visual expression of the hierarchical differences of body composition,
fat mass index and fat-free mass index of the wrestlers in various leagues were
plotted on a body composition chart. Wrestlers in the Sekitori division had
significantly larger fat-free mass index scores in comparison with wrestlers from
the lower divisions who share a common area of the chart. The cut-off point of
fat-free mass index which divided Sekitori wrestlers from other wrestlers is
approximately 30 and this value may be one of the anthropometrical indications of
whether or not a Sumo wrestler is destined to be successful.
Publication Types:
Comparative Study
PMID: 10195655 [PubMed - indexed for MEDLINE]
============
Antimicrob Agents Chemother. 1989 Aug;33(8):1188-92.
Cefotiam disposition in markedly obese athlete patients, Japanese sumo wrestlers.
Chiba K, Tsuchiya M, Kato J, Ochi K, Kawa Z, Ishizaki T.
Division of Clinical Pharmacology, National Medical Center, Tokyo, Japan.
Markedly obese athletes like Japanese sumo wrestlers may frequently suffer
various traumas which result in the prophylaxis or treatment of posttraumatic
infection with antibiotics. However, appropriate dosage regimens in this group of
patients have not been fully known for many antibiotics. Therefore, we studied
the kinetic disposition of cefotiam, a parenteral, broad-spectrum cephalosporin
with activity against gram-positive and -negative bacteria, after an intravenous
dose (2 g) infused over 30 min into 15 sumo wrestler patients with an excess body
weight (130 to 220% of ideal body weight) and 10 control patients with a normal
weight (90 to 102% of ideal body weight). Mean (+/- standard deviation) clearance
and steady-state volume of distribution were significantly greater in the sumo
wrestler than in the control group (38.3 +/- 9.4 versus 23.5 +/- 6.0 liters/h, P
less than 0.001, and 30.2 +/- 8.0 versus 17.9 +/- 6.1 liters, P less than 0.001).
Mean elimination half-life was slightly but significantly longer in the sumo
wrestler than in the control group (0.91 +/- 0.14 versus 0.74 +/- 0.20 h, P less
than 0.05). However, mean residence time did not differ between the two groups
(0.79 +/- 0.10 versus 0.75 +/- 0.14 h). The statistical differences in clearance
and volume of distribution between the two groups disappeared when these kinetic
parameters were corrected for body surface area, but not for total body weight or
ideal body weight. The results suggest that the dosage calculation of cefotiam, a
hydrophilic antibiotic, should be made on the basis of body surface area in
morbidly obese athlete or sumo wrestler patients. However, whether this
recommendation should extend to other nonathlete obese subjects remains to be
determined.
Publication Types:
Research Support, Non-U.S. Gov't
PMID: 2802548 [PubMed - indexed for MEDLINE]
============
Am J Clin Nutr. 1976 Oct;29(10):1167-74.
Some factors related to obesity in the Japanese sumo wrestler.
Nishizawa T, Akaoka I, Nishida Y, Kawaguchi Y, Hayashi E.
Sumo is an ancient sport in Japan and there are at present over 800 professional
sumo wrestlers (rikishis). After entrance into the wrestler society a wrestler
takes strenuous daily training together with a very high calorie diet (more than
5,000 cal). Frequency of food intake is twice a day. The average diet of Japanese
people contains of 2,279 calories and the meal frequency is generally three times
a day. In 96 wrestlers average actual body weight and modified Broca index was
100.4 kg and 143.5%, respectively. In this group the prevalence of overweight
with obesity, overweight without obesity, nonoverweight with obesity, and
nonoverweight without obesity was 53.4, 39.1, 1.0, and 6.5%, respectively. Also
mean serum levels of triglyceride, phospholipid, uric acid, and total protein
were significantly higher than those obtained in 89 age-matched healthy males.
The incidence of diabetes mellitus, gout, and hypertension in wrestlers was 5.2,
6.3, and 8.3%, respectively, all values being considerably higher than in
controls. Weight correlated significantly with skinfold thickness, diastolic
blood pressure, total cholesterol, and uric acid in each group. Multiple
regression analyses were made treating weight or uric acid as dependent variables
in both groups. Obesity, hyperlipidemia, and hyperuricemia in wrestlers were
presumed to be caused chiefly by the high calorie diet and partially by the
infrequent meal intake.
PMID: 973605 [PubMed - indexed for MEDLINE]
============
Am J Cardiol. 2003 Nov 1;92(9):1141.
Comment on:
Am J Cardiol. 2003 Mar 15;91(6):699-703.
Left ventricular dilatation in normotensive, extremely overweight Japanese
professional Sumo wrestlers.
Danias PG, Manning WJ, Tritos NA.
Publication Types:
Comment
Letter
PMID: 14583379 [PubMed - indexed for MEDLINE]
============
Am J Cardiol. 2003 Mar 15;91(6):699-703.
Comment in:
Am J Cardiol. 2003 Nov 1;92(9):1141.
Unusual left ventricular dilatation without functional or biochemical impairment
in normotensive extremely overweight Japanese professional sumo wrestlers.
Kinoshita N, Onishi S, Yamamoto S, Yamada K, Oguma Y, Katsukawa F, Yamazaki H.
Sports Medicine Research Center, Keio University, Yokohama, Japan.
kinoshit at hc.cc.keio.ac.jp <kinoshit at hc.cc.keio.ac.jp>
To explore the physiologic limit of left ventricular (LV) enlargement, we
performed echocardiography and air displacement plethysmography to respectively
assess LV dimension and function and the body composition of Japanese
professional sumo wrestlers. After excluding subjects with cardiovascular
disease, hypertension, plasma brain natriuretic peptide (BNP) > or =17.9 pg/ml,
diabetes mellitus, or asthma, 331 subjects (mean +/- SD age, 21.6 +/- 3.7 years;
height 179.2 +/- 5.3 cm; weight 1,17.9 +/- 21.5 kg; percent fat, 29.6 +/- 6.6%)
were analyzed. LV end-diastolic dimension averaged 58.4 +/- 3.7 mm and was within
the generally regarded normal limit (< or =54 mm) in 14.5% of subjects, but was >
or =60 mm in 41.1% of subjects. LV septal and posterior wall thicknesses were
10.3 +/- 0.9 and 10.2 +/- 0.9 mm, respectively. Peak E- and A-wave velocities,
E/A ratio, LV fractional shortening, and BNP were 96 +/- 16 and 51 +/- 13 cm/s,
2.0 +/- 0.7, 33.5 +/- 4.5%, and 3.1 +/- 3.7 pg/ml, respectively. LV end-diastolic
dimension was not correlated with these indexes of LV function or with plasma BNP
levels, but was significantly correlated with height, weight, body surface area,
fat-free mass, and fat mass. These results show that among very large, highly
trained, professional athletes, LV end-diastolic dimension frequently exceeds the
traditionally accepted upper limit of normal for the general population. This
increase in LV end-diastolic dimension may thus represent an extreme example of
the physiologic adaptation of the athlete's heart.
PMID: 12633801 [PubMed - indexed for MEDLINE]
============
Int J Sports Med. 1997 Oct;18(7):510-5.
Characteristics of body composition and muscle strength in college Sumo
wrestlers.
Kanehisa H, Kondo M, Ikegawa S, Fukunaga T.
Department of Life Sciences (Sports Sciences), University of Tokyo, Japan.
The purpose of this study was to investigate the characteristics of body
composition and force generation capacity in college Sumo wrestlers (N=13,
age=19.8+/-0.3 yr, stature= 178.5+/-1.6 cm, body mass = 111.2+/-3.8 kg, X+/-SE)
in comparison with untrained males (N=18, 20.3+/-0.2 yr, 170.1+/-1.7 cm,
59.2+/-1.4 kg). The Sumo wrestlers had significantly higher average values in
relative fat mass (24.8+/-1.0%) and fat-free mass (83.3+/-2.0 kg), estimated by
an underwater weighing method, than the untrained subjects (relative fat mass =
12.9+/-0.1 %, fat-free mass = 51.5+/-1.3 kg). Moreover, the Sumo wrestlers had
1.7 to 1.9 times greater cross-sectional areas (CSAs) of elbow flexors and
extensors and knee extensors, determined by a B-mode ultrasound technique,
compared to those of the untrained subjects. Force values produced during elbow
flexion and extension and knee extensions tasks under isokinetic contraction mode
at constant velocities of 1.05, 3.14 and 5.24 rad x s(-1) were significantly
higher in the Sumo wrestlers than in the untrained subjects. The force value in
all test conditions was significantly correlated to the related-muscle CSA,
r=0.611-0.910 (p<0.05). The difference between the two groups in force per unit
CSA (F x CSA[-1]) during elbow flexion was not significant at all test
velocities. However, the Sumo wrestlers showed significantly lower F x CSA(-1)
values in elbow extension at 5.24 rad x s(-1) and in knee extension at all test
velocities. Thus, the body composition of the Sumo wrestlers was characterized by
a high fat content and a large fat-free mass. Moreover, the Sumo wrestlers had
considerably larger muscle CSAs of limbs than the untrained subjects. For the
Sumo wrestlers, however, force output of the muscles with a pennate structure
were not proportional to their CSAs, particularly in knee extensors.
Publication Types:
Comparative Study
PMID: 9414073 [PubMed - indexed for MEDLINE]
============
Nippon Eiseigaku Zasshi. 1995 Aug;50(3):730-6.
[Risk factors for mortality and mortality rate of sumo wrestlers]
[Article in Japanese]
Hoshi A, Inaba Y.
Department of Epidemiology and Environmental Health, Juntendo University School
of Medicine, Tokyo, Japan.
We compared the mortality rate of sumo wrestlers with that of the contemporaneous
Japanese male population, and inferred the usefulness of an index for predicting
longevity in sumo wrestlers. The standardized mortality ratios (SMR) for sumo
wrestlers were very high in each period, and also high for ages from 35 to 74.
Cox's proportional hazards model analysis revealed that the variables in
"nyuumaku" entry year and BMI were statistically significant (p < 0.05) factors
in mortality. In the survival curves, the lower BMI group had good life
expectancy compared with the higher BMI group. In conclusion, the higher rate of
mortality in sumo wrestlers seems to be due to the markedly higher rate of
mortality from 35 to 74 years old. In sumo wrestlers, also, this study provides
evidence that the higher overweight groups have substantially higher risks for
mortality.
Publication Types:
English Abstract
PMID: 7474495 [PubMed - indexed for MEDLINE]
============
Br J Nutr. 1983 Jan;49(1):3-7.
Elevated erythrocyte phosphoribosylpyrophosphate and ATP concentrations in
Japanese sumo wrestlers.
Nishida Y, Akaoka I, Hayashi E, Miyamoto T.
1. Japanese sumo wrestlers have a diet rich in energy, which results in marked
obesity. Their plasma urate and triglyceride levels were significantly elevated.
2. Erythrocyte phosphoribosylpyrophosphate (PRPP) and ATP concentrations in sumo
wrestlers were significantly elevated when compared to the levels in control
subjects. 3. There were no significant differences in erythrocyte PRPP synthetase
(EC 2.7.6.1), purine nucleoside phosphorylase (EC 2.4.2.1) and hypoxanthine
guanine phosphoribosyl transferase (EC 2.4.2.8) activities between sumo wrestlers
and control subjects. 4. Erythrocyte adenosine kinase (EC 2.7.1.20), adenosine
deaminase (EC 3.5.4.4) and adenine phosphoribosyl transferase (EC 2.4.2.7)
activities in sumo wrestlers were significantly elevated. 5. It seems that sumo
wrestlers have an increased turnover of adenine nucleotides which may contribute
to hyperuricaemia.
PMID: 6185138 [PubMed - indexed for MEDLINE]
============
J Hum Ergol (Tokyo). 1978 Dec;7(2):103-17.
On the body composition of obese children and in particular, sexual, age, and
regional differences of skinfold thickness.
Sawada Y.
Recently in Japan, it has been observed that the physical dimensions of
schoolboys and schoolgirls, specifically stature and body weight, are increasing
year by year, and that spurts in increase in dimensions tend to happen earlier.
The phenomena of accelerated growth are resulting in more obesity and leanness in
childhood. Skinfold thickness, body density, body fat and lean body mass
estimated from body density, creatinine excretion in the 24-hour urine, and
muscular volume calculated from creatinine excretion were studied in obese
children and normal children of 10 and 11 years of age, and the difference in the
skinfold thickness by sec, age, and district in school children in five districts
in southern Kyushu (1,002 boys and 931 girls) were examined. Reference was then
made to the skinfold thickness of some of experienced and new sumo wrestlers of
the Japan Professional Sumo Association whose nutrition intake is high and who
show high ratios of diabetes mellitus and cardiac diseases. The results of the
present study were also compared with the results of skinfold thickness
measurements of children in Ghana and Kenya and those of the skinfold thickness
and body composition measurements of Czechoslovakian children.
PMID: 756444 [PubMed - indexed for MEDLINE]
============
Am J Clin Nutr. 1976 Oct;29(10):1167-74.
Some factors related to obesity in the Japanese sumo wrestler.
Nishizawa T, Akaoka I, Nishida Y, Kawaguchi Y, Hayashi E.
Sumo is an ancient sport in Japan and there are at present over 800 professional
sumo wrestlers (rikishis). After entrance into the wrestler society a wrestler
takes strenuous daily training together with a very high calorie diet (more than
5,000 cal). Frequency of food intake is twice a day. The average diet of Japanese
people contains of 2,279 calories and the meal frequency is generally three times
a day. In 96 wrestlers average actual body weight and modified Broca index was
100.4 kg and 143.5%, respectively. In this group the prevalence of overweight
with obesity, overweight without obesity, nonoverweight with obesity, and
nonoverweight without obesity was 53.4, 39.1, 1.0, and 6.5%, respectively. Also
mean serum levels of triglyceride, phospholipid, uric acid, and total protein
were significantly higher than those obtained in 89 age-matched healthy males.
The incidence of diabetes mellitus, gout, and hypertension in wrestlers was 5.2,
6.3, and 8.3%, respectively, all values being considerably higher than in
controls. Weight correlated significantly with skinfold thickness, diastolic
blood pressure, total cholesterol, and uric acid in each group. Multiple
regression analyses were made treating weight or uric acid as dependent variables
in both groups. Obesity, hyperlipidemia, and hyperuricemia in wrestlers were
presumed to be caused chiefly by the high calorie diet and partially by the
infrequent meal intake.
PMID: 973605 [PubMed - indexed for MEDLINE]
----- Original Message ----
From: Doreen Simmons <jz8d-smmn at asahi-net.or.jp>
To: Sumo Mailing List <sumo at webtrek.com>
Sent: Friday, June 29, 2007 9:29:26 PM
Subject: Re: [sumo] Question somewhat related to death of rikishi
It's a question I often get asked myself. The first thing is that there
are never enough rikishi to be statistically significant. Statistics
only work with millions, not a few hundred at any one time.
Second, it's the individual deaths that attract attention, especially
when they're relatively young. When a retired rikishi dies in his 80s,
it's not a big news item. Third, a lot of the old 'statistics' ignore
the fact that the life expectancy of ALL Japanese men didn't reach 50
till after WWII. Fourth, the simplistic method of listing the age at
death and dividing by the number of men tends not to take other factors
into account; besides (3) above, there was one 'study' that didn't
notice that a whole lot of inactive or retired sumo-san died on the
same day in the 1945 fire bombing -- Ryogoku was particularly badly hit
and it was natural that many of them should be living here.
In the old days when sugar not salt was used as a seasoning, the
incidence of diabetes was relatively high; and with heavy men high
blood pressure is always a danger; but now it seems to be cancer that
does the most damage and that has nothing to do with the sumo
lifestyle.
There as a recent article (AP?) on this subject; we helped the woman
who was writing it. My colleague found a recent book by a specialist
doctor and recommended it -- but the info is on my office computer.
Just some random thoughts.
Doreen
On 2007/06/30, at 4:17, Magnus Berg wrote:
> Through my web page, I was recently contacted by a reader whose sumo
> interest is often met by the question "Sumo wrestlers die quite young,
> don't they?". I get that question a lot myself, and it's quite
> difficult to answer. Does anyone have recent statistics or even know
> if it is possible to calculate the average life span of today's
> rikishi? I mean, tragic incidents like with Tokitaizan, or even
> ex-Hokutenyu's premature death, are still very rare and many rikishi
> now live to an old age. But how do they compare to the average
> life-span of Japanese (and Mongolian, etc) men?
> Thanks for any input!
> Maguroyama
>
>
>
> ________________________________________________________
> Magnus Berg
> http://www.svenskasumosidan.se
> magnus.rie at comhem.se
>
> _______________________________________________
> Sumo mailing list
> Sumo at webtrek.com
> http://www.webtrek.com/mailman/listinfo/sumo
>
>
Doreen Simmons
jz8d-smmn at asahi-net.or.jp
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