Aerobic performance by children in grades 4 to 8: a repeated-measures study

Aerobic capacity reflects consumption of O2 by working muscles during vigorous physical activity and is an indicator of cardiovascular health. This study examined change in aerobic performance by children in Grades 4 to 8 (Ages= 9-14) over 14 mo. 105 healthy children in a small, rural, middle-class school participated. All were tested five times on the Progressive Aerobic Cardiovascular Endurance Run (PACER) at 8- or 9-wk. intervals during the 2004-2005 school year, with follow-up measurements the next September and December. Hierarchical Linear Modeling applied to analyze the data showed that overall improvement in aerobic performance from September to May was statistically significant as children increased their PACER scores from 26 to 49 laps. These gains were lost over the summer but returned to the original slope by the second follow-up measurement. Regardless of age, sex, Body Mass Index, or sports participation, children followed a similar pattern: steady improvement during the school year, loss of those gains over the summer, and return to the original slope the following year.