Reliable Prediction of Insulin Resistance by a School-Based Fitness Test in Middle-School Children

Abstract

Objectives. (1) Determine the predictive value of a school-based test of cardiovascular fitness (CVF) for insulin resistance (IR); (2) compare a “school-based” prediction of IR to a “laboratory-based” prediction, using various measures of fitness and body composition. Methods. Middle school children (n = 82) performed the Progressive Aerobic Cardiovascular Endurance Run (PACER), a school-based CVF test, and underwent evaluation of maximal oxygen consumption treadmill testing (VO2 max), body composition (percent body fat and BMI z score), and IR (derived homeostasis model assessment index [HOMAIR]). Results. PACER showed a strong correlation with VO2 max/kg (rs = 0.83, P < .001) and with HOMAIR (rs = −0.60, P < .001). Multivariate regression analysis revealed that a school-based model (using PACER and BMI z score) predicted IR similar to a laboratory-based model (using VO2 max/kg of lean body mass and percent body fat). Conclusions. The PACER is a valid school-based test of CVF, is predictive of IR, and has a similar relationship to IR when compared to complex laboratory-based testing. Simple school-based measures of childhood fitness (PACER) and fatness (BMI z score) could be used to identify childhood risk for IR and evaluate interventions.

Aerobic Capacity and Cognitive Control in Elementary School-Age Children

“…The PACER has been implemented in hundreds of thousands of children, as young as 6-years-old, in over 35 countries around the world (28). Correlations between the PACER and VO 2 measures are moderate to strong in nature, ranging from r = 0.65 to 0.83 (25,26,37), with slight deviations based on the age and number of participants included in each study. During the PACER children are instructed to run back and forth between 2 lines, 20-meters apart, paced by a tone on a CD player signaling when they should reach the opposite line.…”

“…Aerobic fitness was assessed using the PACER (31), which has established reliability and validity as a measure of aerobic capacity in children (3,24,25,26,37). The PACER has been implemented in hundreds of thousands of children, as young as 6-years-old, in over 35 countries around the world (28).…”

“…That is, children with higher levels of aerobic fitness commonly exhibit greater academic performance than their less-fit peers on topics such as reading and arithmetic. There is substantial evidence relative to the validity (25,26,37) and test-retest reliability (24,26) of the PACER as an accurate measure of aerobic capacity across a wide age range of children and adolescents (3,28). Despite the apparent influence of fitness on different aspects of cognitive control, surprisingly few studies have attempted to establish whether these relationships persist when using ecologically valid field measures of aerobic fitness.…”

Cognitive control in preadolescent children with risk factors for metabolic syndrome.

“…The PACER has an extensive literature describing the reliability and validity of the test in adults and children (Léger & Lambert, 1982; Léger, Mercier, Gadoury, & Lambert, 1988). Correlations between the PACER and laboratory-based measures of aerobic fitness are moderate to strong, ranging from r = 0.65 to 0.83 (Mahar, Guerieri, Hanna, Kemble, 2011; Varness, Carrel, Eickoff, & Allen, 2009). The PACER was administered in small groups, typically 8–12 students, with at least 1 research staff member per 3 children, and another staff member overseeing the test.…”

The influence of fitness on insulin resistance in obese children

“…We studied children who performed the Progressive Aerobic Cardiovascular Endurance Run (PACER), a school-based CVF test using Fitnessgram, and then underwent evaluation of maximal oxygen consumption treadmill testing (VO 2 max), body composition (percent body fat and BMI Z-score), and IR (derived homeostasis model assessment index-HOMA IR ). Results showed the PACER to be a feasible and costeffective field-based test that correlated very closely (r> 0.8) with CVF in both normal and obese kids and was predictive of IR with a high degree of statistical significance [77]. In this group of children, simple measures of both childhood fitness (PACER) and fatness (BMI) together accurately predicted IR to a greater degree than using BMI alone.…”