Body growth depends on a hormonal stimulus for growth and adequate quality and quantity of nutrients. When nutrients are limiting, growth is stunted. Upon removal of nutritional restraint, catch-up growth occurs. This project attempts to elucidate how nutrition contols growth in an animal model in which spontaneous running stimulates growth of lean body mass and skeleton. To assess how exercise affects hormones of growth, and in conjunction with nutrients, stimulates growth, measurements will be taken of gene activation for synthesis of hormones of growth and of tissue proteins. This study will contribute to the understanding of the mechanism of growth and of the nature of the stimulatory effects of exercise and food energy on growth. The results may provide insights for treatment of children or juvenile animals in whom dietary restriction produces the stunting of growth.
