Abstract
Usage of wearable technology is increasing in popularity every day. Samsung is a popular brand that manufactures wearable fitness trackers capable of measuring body composition (Galaxy Watch7). Because body composition is a common way to determine body fat percentage (FM %) and fat mass (FM), the validity and reliability of wearables to provide accurate measures (body fat percentage and fat mass) during body composition is important. PURPOSE: This study aimed to analyze and assess the validity and reliability of body fat percentage and fat mass from the Samsung Galaxy watch7 vs. DXA scan and Bioelectrical Impedance Analysis (BIA). METHODS: Five adults (3 female, 2 males, identified otherwise n = 0; height = 168.9 ± 6.6 cm; mass = 74.6 ± 11.0 kg) were recruited to participate via convenience sampling. Participants were asked to come to the laboratory well hydrated, avoid alcohol and caffeine, and eat 4h before the test. Participants completed a screening questionnaire as well as for gender and ethnicity. Upon arriving at the laboratory, body composition measures were obtained from the Samsung Galaxy Watch7 twice for reliability analysis, and then from the BIA and DXA (criterion measures) for validity. Outcome measures were body fat percentage (%) and fat mass, recorded in kilogram (kg). Mean Absolute Percent Error (MAPE) and Lin’s Concordance Correlation Coefficient (CCC) were used to assess validity; MAPE ≤ 5% and CCC ≥ 0.90. Coefficient of Variation (CV) was used to assess reliability; CV ≤ 10%. RESULTS: The Samsung Galaxy Watch7 was found to be reliable when percent body fat (FM% CV=2.96%) and fat mass (FM CV=2.95%) were considered. The Samsung Galaxy Watch7 did not meet the thresholds for validity for either measure (FM% MAPE BIA = 10.2%, FM% MAPE DXA = 13.7%; FM CCC BIA = 0.77, FM CCC DXA = 0.55). CONCLUSION: These results indicate that, in the present study, the Samsung Galaxy Watch7 was only reliable for measuring FM% and FM. These results suggest that while individuals may be able to reliably track FM% and FM using a wearable device over time, the actual measures may not be accurate.
Recommended Citation
Zarei, Setareh; Mejia, Rodolfo; and Navalta, James
(2025)
"Validity and Reliability of Wrist-Worn Wearable Body Composition Estimation,"
International Journal of Exercise Science: Conference Proceedings: Vol. 14:
Iss.
5, Article 4.
Available at:
https://digitalcommons.wku.edu/ijesab/vol14/iss5/4