Validation of Accelerometer Prediction Equations in Children with Chronic Disease.

The purpose of this study was to assess the criterion validity of existing accelerometer-based energy expenditure (EE) prediction equations among children with chronic conditions, and to develop new prediction equations. Children with congenital heart disease (CHD), cystic fibrosis (CF), dermatomyositis (JDM), juvenile arthritis (JA), inherited muscle disease (IMD), and hemophilia (HE) completed 7 tasks while EE was measured using indirect calorimetry with counts determined by accelerometer. Agreement between predicted EE and measured EE was assessed. Disease-specific equations and cut points were developed and cross-validated. In total, 196 subjects participated. One participant dropped out before testing due to time constraints, while 15 CHD, 32 CF, 31 JDM, 31 JA, 30 IMD, 28 HE, and 29 healthy controls completed the study. Agreement between predicted and measured EE varied across disease group and ranged from (ICC) .13-.46. Disease-specific prediction equations exhibited a range of results (ICC .62-.88) (SE 0.45-0.78). In conclusion, poor agreement was demonstrated using current prediction equations in children with chronic conditions. Disease-specific equations and cut points were developed.

Feasibility, validity and reliability of the plank isometric hold as a field-based assessment of torso muscular endurance for children 8-12 years of age.

This project examined the feasibility, validity, and reliability of the plank isometric hold for children 8-12 years of age. 1502 children (52.5% female) performed partial curl-up and/or plank protocols to assess plank feasibility (n = 823, 52.1% girls), validity (n = 641, 54.1% girls) and reliability (n = 111, 47.8% girls). 12% (n = 52/431) of children could not perform a partial curl-up, but virtually all children (n = 1066/1084) could attain a nonzero score for the plank. Plank performance without time limit was influenced by small effects with age (ß = 6.86; p < .001, η(2) = 0.03), flexibility (ß = 0.79; p < .001, η(2) = 0.03), and medium effects with cardiovascular endurance (ß = 1.07; p < .001, η(2) = 0.08), and waist circumference (ß = -0.92; p < .001, η(2) = 0.06). Interrater (ICC = 0.62; CI = 0.50, 0.75), intra-rater (ICC = 0.83; CI = 0.73, 0.90) and test-retest (ICC = 0.63; CI = 0.46, 0.75) reliability were acceptable for the plank without time limit. These data suggest the plank without time limit is a feasible, valid and reliable assessment of torso muscular endurance for children 8-12 years of age.