Changes of blood and urine constituents in high school boys during one week intense summer baseball training / 体力科学

ABSTRACT

A study was carried out to confirm the present states of physical training and nutritional condition in sportsmen on the growing stage. Energy expenditure (EE), caloric intake (CI), food items, body weight, running distance for 12 min and hematological and biochemical parameters of blood and urine were measured in 17 high school boys during intense summer baseball training for seven days. EE was estimated from the records by direct observation of activities during the baseball training (RMR method), and CI was calculated from the dietary record supplied each subject for the seven observation day.<BR>Following results were obtained.<BR>1) The average EE was 55.4±7.5 kcal/kg/day, and the CI corresponded to 87.2% of the EE, although no significant reduction of body weight was observed at the termination of the training session.<BR>2) Running distance for 12 min gradually decreased.<BR>3) Significant decreases in serum TG, TP and Hgb concentrations, and a remarkable increase in CPK activity were observed on the 4 th and final days. Urinary excretion of phosphate, urea nitrogen and catecholamines also increased gradually.<BR>4) The greater the increase in negative energy balance (CI-EE), the greater the decrease in TG, TP and Hgb concentrations, and the greater the increase in serum CPK and urinary excretion of catecholamines.<BR>The present results suggest that greater intake of total energy, protein and fat is recommended for development of endurance capacity, baseball techniques and sound growth in occasion such as the present baseball training program in high school boys.