Step count recommendations for children based on body fat.

摘要

OBJECTIVE: Current recommendations for pedometer-determined physical activity in children (boys, 15,000 steps/day; girls, 12,000 steps/day) were based on the association between weekday step counts and body mass index. The objective of this study was to develop new targets using both weekday and weekend step counts with percentage body fat (%BF) as the criterion reference. METHOD: The %BF of 969 New Zealand European, Polynesian, and Asian children (515 male, 454 female) aged 5-12 years was measured in 2004 using hand-to-foot bioelectrical impedance analysis. Weekday and weekend step counts, assessed using sealed multi-day-memory pedometers over 5 days, were combined into a scaled mean step count. The contrasting groups method for determining criterion-referenced cut-off points was used to establish the optimal step count values for predicting overweight (%BF>85th percentile) and non-overweight (%BF<85th percentile). RESULTS: Overweight children had significantly lower mean step counts (14,238+/-3343, boys; 12,555+/-3169, girls) than non-overweight children (16,106+/-3208, boys; 14,176+/-2728, girls). Optimal step count cut-off points were 16,000 steps/day for boys and 13,000 steps/day for girls. CONCLUSION: Step count targets for reducing the risk of excess body fat in children are 1000 steps/day higher than existing BMI-referenced guidelines.