The maximal isometric strength of the knee extension (KES) and cross-sectionl area of m. quadriceps femoris (MQF) were measured on 89 male Japanese elite athletes and 14 untrained men to evaluate the morphological and functional characteristics of athletes in the knee extensor muscles. Athletes were specialized in seven different sport events; 16 sumo wrestlers, 22 oarsmen, 8 volleyball players, 16 speed skaters, 12 association football plyers, 5 sprinters, 10 middle and long distance runners. KES was measured by using a specially designed straingages dynamometer at knee angle of 110 degrees (180 degrees= fully extended) . Cross-sectional area of MQF at the mid-thigh was determined by ultrasonic apparatus. The following results were obtained.
1. Sumo wrestters showed highest mean values (110.18 cm²) in MQF area among athlete groups. Lower mean values in MQF area were found in sprinters (86.34 cm²) and distance runners (73.86 cm²) whose values were not significantly different from that of untrained (75.32 cm²) .
2. In the cross-sectional area of each muscle bundle of MQF, sumo wrestlers, volleyball players and speed skaters showed higher mean values, and sprinters and distance runners had lower mean values as well as untrained men.
3. Higher mean values in percentage of MQF area to the total muscle area of thigh were observed in volleyball players (58.66%) and oarsmen (57.53%), lower mean value in association football players (53.81%), respectively. However, there were no significant differences in percentage of MQF area between untrained and each athlete group.
4. In the percentage of each muscle bundle area to MQF area, m. rectus femoris of association football players and m. vastus lateralis of speed skaters were significantly higher mean values compared with the untrained and other athlete groups.
5. KES were significantly related to the MQF area at 0.1% level (r=0.657) . There were significant relationships KES and each muscle bundle area in MQF area at 0.1% level. In the relationship between KES and each muscle bundle area, m. vastus lateralis showed the highest correlation coefficient (r=0.603) .
6. Association football players showed highest mean value (8.97 N/cm²) in KES per unit of MQF area among athlete groups. Its value was significantly higher than that of untrained men (8.06 N/cm²), distance runners (7.31 N/cm²), volleyball players (7.10N/cm²), and sumo wrestlers (7.50N/cm²) . There were no significant differences in KES per unit of MQF area intra athlete groups except for association football players.

There are various diseases of the gallbladder and cystic duct, and imaging diagnosis is challenging for the rare among them. However, some rare diseases show characteristic imaging findings or patient history; therefore, familiarity with the imaging presentation of rare diseases may improve diagnostic accuracy and patient management. The purpose of this article is to describe the imaging findings of rare diseases of the gallbladder and cystic duct and identify their pathological correlations with these diseases.

There are various diseases of the gallbladder and cystic duct, and imaging diagnosis is challenging for the rare among them. However, some rare diseases show characteristic imaging findings or patient history; therefore, familiarity with the imaging presentation of rare diseases may improve diagnostic accuracy and patient management. The purpose of this article is to describe the imaging findings of rare diseases of the gallbladder and cystic duct and identify their pathological correlations with these diseases.

OBJECTIVES: One of the important risk factors of falling is decreased muscle mass and muscle strength. Recently, there has been an increasing concern on the role of vitamin D in muscle strength and physical activity. Aim of our study is to examine the relationships between vitamin D status and muscle mass and muscle strength in middle-aged healthy adults. METHODS: Subjects were 40 healthy volunteers aged 42.0 ± 10.6 years old. Evaluation was made for serum vitamin D₃ metabolites including 25-hydroxyvitamin D₃ [25(OH)D₃] and 24,25-dihydroxyvitamin D₃ [24,25(OH)₂D₃] concentrations, lower limb muscle strength, and dietary intake by food frequency questionnaire. Body composition was measured by dual-energy X-ray absorptiometry (DXA), and appendicular skeletal mass index (ASMI) was calculated as skeletal muscle mass/squared height. RESULTS: 70% of the subjects had vitamin D insufficiency/deficiency (serum total 25(OH)D < 20 ng/mL), and female subjects had significantly lower serum total 25(OH)D level compared with males. Vitamin D insufficiency/deficiency group had significantly higher body fat, lower SMI and muscle strength, probably reflecting higher percentage of female subjects. Serum vitamin D₃ metabolites levels were significantly correlated with whole and site-specific ASMI, and lower limb muscle strength, except for the correlation between serum 24,25(OH)₂D₃ concentration and lower limb muscle strength. In addition, serum 25(OH)D₃ level was a positive significant predictor for both ASMI and lower limb muscle strength, while serum 24,25(OH)₂D₃ level was not their significant predictor. CONCLUSIONS: Serum 25(OH)D₃ level was significantly correlated with both skeletal muscle mass and lower limb muscle strength.
Absorptiometry, Photon ; Accidental Falls ; Adipose Tissue ; Adult ; Asian Continental Ancestry Group* ; Body Composition ; Calcifediol* ; Female ; Healthy Volunteers ; Humans ; Lower Extremity* ; Male ; Motor Activity ; Muscle Strength* ; Muscle, Skeletal* ; Risk Factors ; Vitamin D ; Vitamins