Related Experiment Video
Updated: Feb 13, 2026

Design and Evaluation of Smart Glasses for Food Intake and Physical Activity Classification
Published on: February 14, 2018
Relationship Among Changes in Sedentary Time, Physical Activity, and Body Mass Index in Young Schoolchildren: A
Amanda Santos1, Sandra Silva-Santos1, Michael Duncan2
11 University of Porto.
Purposes:
To examine the association between sedentary time (ST) and light physical activity (LPA), moderate- to vigorous-intensity physical activity (MVPA), and body mass index (BMI), and to track these behaviors over a 3-year follow-up in young schoolchildren.
Methods:
The final sample was 64 children (female: n = 36 or 56.3%), enrolled in schools in Porto, Portugal. Height and mass of children were measured by standard methods, and BMI was then calculated. ST, LPA, and MVPA were measured by accelerometer. Changes (Δ) and relative changes (Δ%) between 2009/2010 and 2012/2013 of ST, LPA, MVPA, and BMI were computed. Multiple linear regression analyses were fit to predict Δ%ST (outcome variable), by Δ%LPA, Δ%MVPA, and Δ%BMI (exposure variables).
Results:
ST increased and LPA decreased significantly for whole sample (both Ps < .05). No statistically significant difference was found for MVPA over time. There were no differences for ΔST, ΔLPA, ΔMVPA, and ΔBMI between boys and girls. The Δ%LPA and Δ%MVPA were negatively associated with Δ%ST, whereas Δ%BMI was positively associated. Tracking coefficients varied from moderate to strong.
Conclusions:
Time spent in ST increases due to displacement of time in LPA. This reinforces public health measures and suggests the need for interventions focusing on offsetting the decline ST and increasing MVPA during childhood.
More Related Videos
05:59Visualization of Intensity Levels to Reduce the Gap Between Self-Reported and Directly Measured Physical Activity
Published on: March 7, 2019
09:18Time-resolved ElectroSpray Ionization Hydrogen-deuterium Exchange Mass Spectrometry for Studying Protein Structure and Dynamics
Published on: April 17, 2017
Related Concept Videos
Longitudinal Research
Longitudinal Studies
Relationship Formation
Structure-Activity Relationships and Drug Design
SAR studies the intricate relationship between a drug's chemical structure and biological activity. It focuses on understanding how modifications to a drug's structure can influence...
Reduced Mass Coordinates: Isolated Two-body Problem
ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3