The relation of body build to the excretion of 17-ketosteroids and 17-ketogenic steroids in healthy young men.

Abstract

SUMMARY 1. The 24 hr excretions of 17-ketosteroids (17-KS), 17-ketogenic steroids (17-KGS) and creatinine of 101 healthy young men have been measured on two occasions several weeks apart to determine what, if any, relationship these bore to the subjects' body build. 2. Body build was assessed by anthropometric measurements, somatotyping, and a new method detailing the limb widths of fat, muscle and bone. 3. The week-to-week personal constancy coefficient of each of these excretions has been calculated. It is highest for 17-KS (0·83), and slightly lower for 17-KGS (0·73) and creatinine (0·72). 4. Correlations have been calculated both for between-persons relationships ('stable' or 'habitual'individuals' values) and within-persons relationships (daily individual co-fluctuations). The stable values of 17-KS and 17-KGS excretions are inversely related, individuals habitually high in one being habitually low in the other. This relationship becomes more marked when allowances are made for surface area and urine volume differences. 5. Excretion of 17-KS is significantly related to body weight and to mesomorphy. The multiple correlation with muscle width and weight was 0·56. 6. Excretion of 17-KGS is significantly related to weight and height. This is due to a positive relation with width and length of the limb bones (multiple correlation 0·55). There is no relation with muscle mass or subcutaneous fat thickness. 7. On the basis of these findings speculations are made on the possible role of 17-KS in maintaining muscle bulk and of corticosteroids in maintaining the contents of the medulla of the limb bones. 8. There is a significant, though quantitatively small, correlation between general body hirsutism, muscle bulk and 17-KS output. There is a similar-sized but inverse relation between penis size and amount of subcutaneous fat. 9. Recent findings on the relation of physique to resistance to tuberculosis are discussed in the light of the above findings. These point to the conclusion that more bodily measurements than simple weight and height must be taken if useful information as to causes of the physique-disease relationship is to be obtained.