RESUMO
Canadian movement guidelines focused on physical activity (PA), sleep, and screen time support childhood development and reduce the risk of chronic disease. Accelerometers are often used to capture these behaviors; however, they are limited in their ability to record daytime sleep due to potential misclassification. OBJECTIVES: The objectives of this study were to 1) determine the prevalence of children enrolled in the Guelph Family Health Study who met the guidelines and to 2) compare the impact of different sleep measurement methods. DESIGN/METHODS: Toddlers (1.5-<3â¯years; nâ¯=â¯128; valid data for all movement behaviors, nâ¯=â¯70), preschoolers (3-<5â¯years; nâ¯=â¯143; valid data for all movement behaviors, nâ¯=â¯104), and school-aged (5-<6â¯years; nâ¯=â¯49; valid data for all movement behaviors, nâ¯=â¯31) children were included. Screen time and sleep habits were obtained through parental report and published normative data. PA and sleep were recorded using accelerometers (wGT3X-BT ActiGraph; right hip). RESULTS: It was found that 66â¯% of toddler, 44â¯% of preschool, and 63â¯% of school-aged children met the screen time guidelines. Further, 63â¯% of toddler, 98â¯% of preschooler, and 80â¯% of school-aged children met PA guidelines. Sleep guideline compliance ranged from 3â¯% to 83â¯% in toddler, 27â¯% to 92â¯% in preschooler, and 32â¯% to 90â¯% in school-aged children. These proportions were found to be significantly different (Cochran's Q and McNemar's tests). CONCLUSIONS: Nearly all children met PA guidelines. In contrast, less than half to two-thirds met screen time guidelines. Compliance with sleep guidelines varied substantially with measurement method, highlighting the need for standardization.
RESUMO
The ActiGraph GT9X has been implemented in clinical trials to track physical activity and sleep. Given recent incidental findings from our laboratory, the overall aim of this study was to notify academic and clinical researchers of the idle sleep mode (ISM) and inertial measurement unit (IMU)'s interaction, as well as their subsequent effect on data acquisition. Investigations were undertaken using a hexapod robot to test the X, Y and Z sensing axes of the accelerometers. Seven GT9X were tested at frequencies ranging from 0.5 to 2 Hz. Testing was performed for three sets of setting parameters: Setting Parameter 1 (ISMONIMUON), Setting Parameter 2 (ISMOFFIMUON), Setting Parameter 3 (ISMONIMUOFF). The minimum, maximum and range of outputs were compared between the settings and frequencies. Findings indicated that Setting Parameters 1 and 2 were not significantly different, but both were significantly different from Setting Parameter 3. Upon inspection, it was discovered that the ISM was only active during Setting Parameter 3 testing, despite it being enabled in Setting Parameter 1. Researchers should be aware of this when conducting future research using the GT9X.
Assuntos
Acelerometria , Exercício Físico , SonoRESUMO
This study compares sleep outcome measures obtained using normal- and low-frequency extension (LFE) settings (Actilife). Forty-two children (aged 3-6 years) were instructed to wear an ActiGraph GT3X+ accelerometer on their hip for 7 days, 24 h/day. Total sleep time (min), sleep efficiency (%), and number and cumulative length (min) of awakening were used to compare the settings. Results suggest that the LFE setting results in significant but relatively small reductions in the sleep metrics of children. Trial registration no.: clincialtrials.gov (ID no. NCT02223234) Novelty LFE setting, available through ActiGraph, estimates a significantly reduced total sleep time and efficiency.