TY - JOUR
T1 - Associations of physical activity level and variability with 6-month weight change among 26,935 users of connected devices
T2 - Observational real-life study
AU - El Fatouhi, Douae
AU - Delrieu, Lidia
AU - Goetzinger, Catherine
AU - Malisoux, Laurent
AU - Affret, Aurélie
AU - Campo, David
AU - Fagherazzi, Guy
N1 - Funding Information:
The authors would like to thank the anonymous reviewers for their thorough review and Dr Joseph Rothwell for careful proofreading of the manuscript. DE was supported by a doctoral grant from the French National Cancer Institute (INCa_13563). This study was also supported by the French Research Agency ANR (Agence Nationale de la Recherche) via an ?Investissement d'Avenir? grant (investment for the future grant, ANR-10- COHO-0006), which supports the E4N study. GF is supported by the Luxembourg Institute of Health. CG is supported by a doctoral grant from LIONS, a Luxembourgish association that supports cancer research. Study funders and sponsors had no role in the design of the study, analysis or interpretation of data, writing of the manuscript, or decision to submit the manuscript for publication. The data sets generated and/or analyzed during this study are available from the corresponding author on reasonable request and with permission from the Withings company.
Publisher Copyright:
© Douae El Fatouhi, Lidia Delrieu, Catherine Goetzinger, Laurent Malisoux, Aurélie Affret, David Campo, Guy Fagherazzi. Originally published in JMIR mHealth and uHealth (http://mhealth.jmir.org), 15.04.2021. This is an open-access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in JMIR mHealth and uHealth, is properly cited. The complete bibliographic information, a link to the original publication on http://mhealth.jmir.org/, as well as this copyright and license information must be included.
PY - 2021/4/15
Y1 - 2021/4/15
N2 - Background: Physical activity (PA) is a modifiable lifestyle factor that can be targeted to increase energy expenditure and promote weight loss. However, the amount of PA required for weight loss remains inconsistent. Wearable activity trackers constitute a valuable opportunity to obtain objective measurements of PA and study large populations in real-life settings. Objective: We aim to study the associations of initial device-assessed PA characteristics (average step counts and step count variability) and their evolution with 6-month weight change. Methods: We analyzed data from 26,935 Withings-connected device users (wearable activity trackers and digital scales). To assess the initial PA characteristics and their 6-month changes, we used data recorded during the first and sixth 30-day periods of activity tracker use. For each of these periods, we used the monthly mean of daily step values as a proxy for PA level and derived the monthly coefficient of variation (CV) of daily step values to estimate PA level variability. Associations between initial PA characteristics and 6-month weight change were assessed using multivariable linear regression analyses controlled for age, sex, blood pressure, heart rate, and the predominant season. Restricted cubic spline regression was performed to better characterize the continuous shape of the associations between PA characteristics and weight change. Secondary analyses were performed by analyzing the 6-month evolution of PA characteristics in relation to weight change. Results: Our results revealed that both a greater PA level and lower PA level variability were associated with weight loss. Compared with individuals who were initially in the sedentary category (<5000 steps/day), individuals who were low active (5000-7499 steps/day), somewhat active (7500-9999 steps/day), and active (≥10,000 steps/day) had a 0.21-kg, a 0.52-kg, and a 1.17-kg greater decrease in weight, respectively (95% CI −0.36 to −0.06, −0.70 to −0.33, and −1.42 to −0.93, respectively). Compared with users whose PA level CV was >63%, users whose PA level CV ranged from 51% to 63%, 40% to 51%, and was ≤40%, had a 0.19-kg, a 0.23-kg, and a 0.33-kg greater decrease in weight, respectively (95% CI −0.38 to −0.01, −0.41 to −0.04, and −0.53 to −0.13, respectively). We also observed that each 1000 steps/day increase in PA level over the 6-month follow-up was associated with a 0.26-kg (95% CI −0.29 to −0.23) decrease in weight. No association was found between the 6-month changes in PA level variability and weight change. Conclusions: Our results add to the current body of knowledge that health benefits can be observed below the 10,000 steps/day threshold and suggest that not only increased mean PA level but also greater regularity of the PA level may play important roles in short-term weight loss.
AB - Background: Physical activity (PA) is a modifiable lifestyle factor that can be targeted to increase energy expenditure and promote weight loss. However, the amount of PA required for weight loss remains inconsistent. Wearable activity trackers constitute a valuable opportunity to obtain objective measurements of PA and study large populations in real-life settings. Objective: We aim to study the associations of initial device-assessed PA characteristics (average step counts and step count variability) and their evolution with 6-month weight change. Methods: We analyzed data from 26,935 Withings-connected device users (wearable activity trackers and digital scales). To assess the initial PA characteristics and their 6-month changes, we used data recorded during the first and sixth 30-day periods of activity tracker use. For each of these periods, we used the monthly mean of daily step values as a proxy for PA level and derived the monthly coefficient of variation (CV) of daily step values to estimate PA level variability. Associations between initial PA characteristics and 6-month weight change were assessed using multivariable linear regression analyses controlled for age, sex, blood pressure, heart rate, and the predominant season. Restricted cubic spline regression was performed to better characterize the continuous shape of the associations between PA characteristics and weight change. Secondary analyses were performed by analyzing the 6-month evolution of PA characteristics in relation to weight change. Results: Our results revealed that both a greater PA level and lower PA level variability were associated with weight loss. Compared with individuals who were initially in the sedentary category (<5000 steps/day), individuals who were low active (5000-7499 steps/day), somewhat active (7500-9999 steps/day), and active (≥10,000 steps/day) had a 0.21-kg, a 0.52-kg, and a 1.17-kg greater decrease in weight, respectively (95% CI −0.36 to −0.06, −0.70 to −0.33, and −1.42 to −0.93, respectively). Compared with users whose PA level CV was >63%, users whose PA level CV ranged from 51% to 63%, 40% to 51%, and was ≤40%, had a 0.19-kg, a 0.23-kg, and a 0.33-kg greater decrease in weight, respectively (95% CI −0.38 to −0.01, −0.41 to −0.04, and −0.53 to −0.13, respectively). We also observed that each 1000 steps/day increase in PA level over the 6-month follow-up was associated with a 0.26-kg (95% CI −0.29 to −0.23) decrease in weight. No association was found between the 6-month changes in PA level variability and weight change. Conclusions: Our results add to the current body of knowledge that health benefits can be observed below the 10,000 steps/day threshold and suggest that not only increased mean PA level but also greater regularity of the PA level may play important roles in short-term weight loss.
KW - Connected devices
KW - Digital health
KW - Digital scale
KW - Free-living
KW - Mobile phone
KW - Physical activity
KW - Step count
KW - Wearable activity trackers
KW - Weight loss
KW - Withings
UR - http://www.scopus.com/inward/record.url?scp=85104394509&partnerID=8YFLogxK
UR - https://www.ncbi.nlm.nih.gov/pubmed/33856352
U2 - 10.2196/25385
DO - 10.2196/25385
M3 - Article
C2 - 33856352
AN - SCOPUS:85104394509
SN - 2291-5222
VL - 9
SP - e25385
JO - JMIR mHealth and uHealth
JF - JMIR mHealth and uHealth
IS - 4
M1 - e25385
ER -