Sumo the Japanese traditional form of wrestling is a unique and very popular sport, and particularly among the professionals the ancient ceremonial rites are still in practice. The wrestlers are of gigantic stature and consist mostly of men of the pyknic type and are considered to possess great strength. Actually, the Shindeshi or novices are selected from boys under 18 years of age and having a body height of over 170 cm and weighing over 70 kg.<BR>The present paper deals with a study on the physique and physical fitness of 103 Shindeshi who entered the professional Sumo world in 1970 and 1971.<BR>The results of the investigation were as follows:<BR>1) The average age and body measurements of the experimental subjects are shown in Table 1. The average body height and average body weight of 174.5 com and 90.9 kg, respectively, of the Shindeshi when compared to those of the average 16 year old male, are remarkably great. Of particular interest are the girth measurements which showed remarkable development: chest, 103.4 cm, waist, 93.0cm and hip, 105.0cm.<BR>2) As a result, Rohrer's index was found to 171.8 and the average of the total skinfold thickness (upper arm, back, abdomen) was 81.3 mm indicating a remarkably pyknic type. Consequently, it is only natural that high correlation values of 0.927 and 0.937, respectively, for the waist and outstretched upper arm are established.<BR>3) Body density computed by Nagamine and Suzuki's equation was found to be 1.034 and body fat calculated by Keys and Brozek's equation was found to be 25.3%, both indicating values twice as high as those of the average male of comparable age, proving that the Shindeshi belong to the ultra-pyknic type.<BR>4) Results of measurements of muscle strength and motor capacity are shown in Table 4 and in Fig. 1 these measurements are compared to the average male of comparable age.<BR>The average back strength was 152.9 kg and the average grip strength, 52.0 kg, indicating remarkably higher values than the average youth. However, it is noteworthy that according to the results of physical fitness tests provided by the Ministry of Education including forward flexibilit, backward flexibility, vertical jump, and step test, the Shindeshi were found to have inferior motor capacity than the average youths of comparable age.<BR>5) And, as shown in Table 4 a significant inverse relation was found between motor capacity and skinf old thickness Rohrer's index and body fat.<BR>6) Three groups totalling 12 Shindeshi were formed according to the degree of skinfold thickness in order to determine their work capacity. The bicycle ergometer was used and the maximal oxygen uptake of the experimental subjects was measured (Table 6) . Proportionate to their large physique, the maximal oxygen uptake was comparatively high (3.6-3.91), however, when converted into the uptake per kilogram of body weight, it was found that although higher than the average youths of comparable age, the uptake (46.9ml/kg-32.0m1/kg) was lower than that of sportsmen in other field of sport.<BR>From the foregoing, it may be inferred that the Shindeshi, although large in physique lack endurance as attested by a compartively low oxygen uptake. It is also interesting to note that from the special characteristics of Sumo this capacity to endure is not necessarily required.