This article has no abstract; the first 100 words appear below.
MUCH has been written about the adolescent in the last decade. The changes that occur during adolescence in body mass as well as function are dramatic. As an example, body weight may double in boys from twelve through eighteen years. There is a less dramatic though notable spurt in osseous development manifested by increments in height, which may be as much as 8 inches in a single year. Less emphasis has been placed on the changes in physiologic function during adolescence. In the preparation of this review it became increasingly clear that many of the sex differences in physiologic functioning . . .