A comparison of the utility of different step-indices to translate the physical activity recommendation in adolescents

ABSTRACT

Previous studies translating the daily moderate-to-vigorous physical activity (MVPA) recommendation of total steps/day among adolescents are inconsistent, and those with cadence-based steps are scarce. The main purpose was to compare the accuracy of different daily steps index-based cut-points related to the daily 60 minutes of MVPA recommendation measured by a waist-worn accelerometer for adolescents. Following a cross-sectional design, 428 Spanish adolescents (final sample 351, 50.4% males), aged 13−16 years old, wore an ActiGraph GT3X/+ accelerometer (reference standard = MVPA; index tests = total steps/day, average steps/min and peak 1-min cadence) on the right hip for eight consecutive days. 32.5% of the adolescents met the daily MVPA recommendation. The multiple ROC curve comparisons showed that the accuracy of the daily total step-based recommendation (AUC = 0.97) was statistically higher than for those with the steps/min (AUC = 0.90) and peak 1-min cadence (AUC = 0.58) (p < 0.001). The 10,000-step-per-day cut-point (k= 0.59−0.83) showed highest accuracy values than the 12,000 steps/day (k= 0.20−0.32). Daily total step-based recommendations are more accurate than those with steps/min and peak 1-min cadence for classifying adolescents as being physically active or inactive. A 10,000-step-per-day target is simple and accurate for both male and female adolescents.

KEYWORDS:

• Activity trackers
• steps per day
• step counts
• walking cadence
• thresholds
• youth

Disclosure statement

The authors report no conflict of interest. The funder had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Geolocation information

Sample A: 37°10ʹ31.9”N, 3°36ʹ53.6”W, 37.175531, −3.614880; Sample B: 37°08ʹ37.6”N, 3°38ʹ22.7”W, 37.143788, −3.639645

Key learning points

Daily total step-based recommendations are more accurate than those with steps/min and peak 1-min cadence for classifying adolescents as being physically active or inactive.

A 10,000 steps/day target measured by a waist-worn accelerometer is simple and accurate for both male and female adolescents.

There was no difference between males and females.

Supplemental data

Supplemental data for this article can be accessed online here.

Additional information

Funding

This work was supported by the Spanish Ministry of Science, Innovation and Universities (Carolina Casado-Robles, FPU16/03314).