Activity wristband-based physical activity recommendations in young people

Abstract

The main aim of the present study was to establish daily activity wristband-measured steps thresholds related to the recommendation of 60 minutes of moderate-to-vigorous physical activity daily in adolescents. The secondary aims of this study were twofold: (a) to establish daily activity wristband-measured total physical activity and moderate-to-vigorous physical activity thresholds; and (b) to examine the cross-validity of daily activity wristband-measured steps thresholds established in previous studies associated with the recommended 60 minutes per day of moderate-to-vigorous physical activity in adolescents. Following a cross-sectional design, 85 Spanish adolescents (including 56 females; aged 12–18 years old) from a public high school wore an ActiGraph GT3X+ accelerometer and four activity wristbands (Xiaomi Mi Band 2, Fitbit Alta HR, Polar A360 and Garmin Vivofit 4; non-dominant hand; index tests) for a day. A total of 38.8% of the adolescents met the moderate-to-vigorous physical activity recommendation. The results showed that the validity of the daily total step-based thresholds tended to be higher (e.g., AUC = 0.83–0.91, P < 0.001) than those with total physical activity or moderate-to-vigorous physical activity (AUC = 0.66–0.88, P < 0.01). The results of the cross-validity showed that the 10,000 step-per-day threshold had a high agreement (e.g., Xiaomi, P = 0.80; k = 0.58; Garmin, P = 0.82; k = 0.63). Activity wristband-measured total steps thresholds have a high validity for translating the daily moderate-to-vigorous physical activity recommendation, being more preferable than those with total physical activity or moderate-to-vigorous physical activity. A 10,000 step-per-day target seems to be a practical and adequate activity wristband-based threshold among adolescents. This knowledge may help policy makers to provide adequate daily activity wristband-measured step-based recommendations for adolescents.