adolescent growth spurt

Period during adolescence of rapid growth rate, usually expressed as the age of peak height velocity (peak body mass velocity usually occurs some months later). Most girls have their adolescent growth spurt between the age of 12 and 13 years; the growth spurt of most boys occurs between the age of 14 and 15 years. During the growth spurt, young people are particularly prone to sports injuries because a discrepancy between bone matrix formation and bone mineralization diminishes bone strength. In addition, the growth plates in bones are extremely vulnerable to external forces. Repetitive, moderate to high-intensity activities (e.g. distance running and baseball pitching) can easily overload the musculoskeletal system causing injuries, such as Osgood-Schlatter disease and little leaguer's elbow.