Title; Determining the correlation of vital capacity of 11 to 17 years old girl students measured by spirometry and Allometry equation in Tehran

The aim of this study was to determine the correlation of vital capacity of 11 to 17-year-old girl students measured by spirometry and allometry equation. For this purpose, a number of 311 girl students with average of age 14±3 years and average of weight 48/83±9 Kg and average of height 153±76 cm were selected and their vital capacity were calculated by spirometer and also through allometric equation. Then, the statistical method of Piersson's Correlation coefficient was used to assess the correlation between two method of measurement of vital capacity. The statistical method of t test in independent groups was used to assess the difference between vital capacity’s mean of athlete group and non-athlete. the analysis of the data showed that allometric equation enjoys high validity in determining the vital capacity of 11 to 17 years old girl students. (r=0.83 and α=0.86). and there is not difference between vital capacity’s mean of athlete group and non-athlete. There for the result of this research shows that allometric equation can be used for determining the vital capacity of girl students in the conditions when exercise laboratory and spirometer are not available.