A Comparison Of Two Qualitative MVPA Scoring Protocols: Youth Met Y Cut-points Require Further Exploration

Abstract

Qualitative measures of activity have been traditionally described utilizing MET values. Notably, activity intensity is categorized as moderate if MET values range from 3.0-5.9; activities with 6.0+ METs are categorized as vigorous-intensity. Recently, the Youth Compendium of Physical Activities was released by an NCCOR workgroup in response to concerns that adult MET energy expenditure values may not accurately account for age differences in basal metabolic rates. However, the Youth Compendium does not currently provide adjusted METy moderate-vigorous activity (MVPA) cut-points for youth, resulting in potential research errors such as over-reporting of a child’s MVPA. PURPOSE: To determine if average MVPA energy expenditure values would significantly differ when two youth scoring protocols (the traditional Three-Day Physical Activity Recall (3DPAR) vs. new NCCOR Youth Compendium) were compared across repeated measures in a sample of pre-adolescent girls. METHODS: Study participants completed detailed 7-day PA logs at study baseline (BL), 1-week follow-up (FU1), and 3-month follow-up (FU2). All self-reported activities were coded with MET (3DPAR) or METy (NCCOR Youth Compendium) energy expenditure (EE) values from each protocol’s respective activity repository. Conservatively, if multiple EE values were available per activity, the lowest value was selected. Activities were considered MVPA if MET/METy metrics exceeded 3.0. RESULTS: At all data collection times, mean volume of MVPA was greatest when utilizing the NCCOR protocol. Group differences between the scoring protocols were significant when examining both weekday (BL/FU1/FU2: p < .001) and weekend activity (BL/FU1/FU2: p < .001). CONCLUSION: To our knowledge, this is the first study which provides comparisons of two qualitative MVPA scoring protocols utilizing repeated measures analyses of EE values in youth. Thus, findings may be important to future research using self-report activity data. In the current study, adult cut-points for MVPA were applied to the Youth Compendium scoring protocol, although literature suggests that EE of similar activities is higher for children than adults. Consequently, we urge that higher MVPA cut-points for the Youth Compendium be explored to more accurately capture measures of PA epidemiology in youth.