Estimation of Aerobic Fitness From PACER Performance in Older Adolescents

Background/Purpose The purpose of this study was to develop a regression model to estimate VO₂max from PACER performance in adolescents. A secondary purpose was to examine the criterion-referenced validity of the models.

Method Participants included 22 females and 26 males aged 17 to 18 years. The PACER was completed and percent fat was measured with air displacement plethesmography. VO₂max was directly assessed during a maximal treadmill test.

Analysis/Results Regression analysis was used to predict VO₂max from number of laps completed on the PACER, age, gender, body mass, and body mass index or percent fat. VO₂max averaged 41.9±9.9 ml^.kg^-1.min^-1 for males and 33.1±6.7 ml^.kg^-1.min^-1 for females. The only variable that significantly contributed to estimation of VO₂max was PACER laps completed. The model developed on the current sample was: VO₂max=20.41012+(PACER laps*0.41304) (R =.89; SEE=4.36 ml^.kg^-1.min^-1). Classification accuracy of the models was examined for three FITNESSGRAM categories (Healthy Fitness Zone [HFZ], Needs Improvement–Some Risk, and Needs Improvement–High Risk) and two categories (HFZ and Needs Improvement). Proportion of agreement was moderate for the three category analysis (Pa=.73) and high for the two category analysis (Pa=.88).

Conclusions The prediction model developed in the current study provides an accurate estimate of VO₂max. The variable of laps completed on the PACER was the only significant contributor to the equation. Previously published equations were evaluated and were notably less accurate than this new model. The current prediction model also produced accurate classification of fitness levels into the Healthy Fitness Zone or Needs Improvement Zone.