TY  - JOUR
AU  - Zahrt, Octavia Hedwig
AU  - Evans, Kristopher
AU  - Murnane, Elizabeth
AU  - Santoro, Erik
AU  - Baiocchi, Michael
AU  - Landay, James
AU  - Delp, Scott
AU  - Crum, Alia
PY  - 2023
DA  - 2023/1/25
TI  - Effects of Wearable Fitness Trackers and Activity Adequacy Mindsets on Affect, Behavior, and Health: Longitudinal Randomized Controlled Trial
JO  - J Med Internet Res
SP  - e40529
VL  - 25
KW  - physical activity
KW  - health technology
KW  - psychology
KW  - mindset
KW  - mobile health
KW  - mHealth
KW  - activity trackers
KW  - fitness trackers
KW  - activity monitors
KW  - wearables
KW  - health behavior
KW  - digital health
KW  - health promotion
KW  - intervention
KW  - mobile phone
AB  - Background: There is some initial evidence suggesting that mindsets about the adequacy and health consequences of one’s physical activity (activity adequacy mindsets [AAMs]) can shape physical activity behavior, health, and well-being. However, it is unknown how to leverage these mindsets using wearable technology and other interventions. Objective: This research examined how wearable fitness trackers and meta-mindset interventions influence AAMs, affect, behavior, and health. Methods: A total of 162 community-dwelling adults were recruited via flyers and web-based platforms (ie, Craigslist and Nextdoor; final sample size after attrition or exclusion of 45 participants). Participants received an Apple Watch (Apple Inc) to wear for 5 weeks, which was equipped with an app that recorded step count and could display a (potentially manipulated) step count on the watch face. After a baseline week of receiving no feedback about step count, participants were randomly assigned to 1 of 4 experimental groups: they received either accurate step count (reference group; 41/162, 25.3%), 40% deflated step count (40/162, 24.7%), 40% inflated step count (40/162, 24.7%), or accurate step count+a web-based meta-mindset intervention teaching participants the value of adopting more positive AAMs (41/162, 25.3%). Participants were blinded to the condition. Outcome measures were taken in the laboratory by an experimenter at the beginning and end of participation and via web-based surveys in between. Longitudinal analysis examined changes within the accurate step count condition from baseline to treatment and compared them with changes in the deflated step count, inflated step count, and meta-mindset conditions. Results: Participants receiving accurate step counts perceived their activity as more adequate and healthier, adopted a healthier diet, and experienced improved mental health (Patient-Reported Outcomes Measurement Information System [PROMIS]-29) and aerobic capacity but also reduced functional health (PROMIS-29; compared with their no-step-count baseline). Participants exposed to deflated step counts perceived their activity as more inadequate; ate more unhealthily; and experienced more negative affect, reduced self-esteem and mental health, and increased blood pressure and heart rate (compared with participants receiving accurate step counts). Inflated step counts did not change AAM or most other outcomes (compared with accurate step counts). Participants receiving the meta-mindset intervention experienced improved AAM, affect, functional health, and self-reported physical activity (compared with participants receiving accurate step counts only). Actual step count did not change in either condition. Conclusions: AAMs––induced by trackers or adopted deliberately––can influence affect, behavior, and health independently of actual physical activity. Trial Registration: ClinicalTrials.gov NCT03939572; https://www.clinicaltrials.gov/ct2/show/NCT03939572 
SN  - 1438-8871
UR  - https://www.jmir.org/2023/1/e40529
UR  - https://doi.org/10.2196/40529
UR  - http://www.ncbi.nlm.nih.gov/pubmed/36696172
DO  - 10.2196/40529
ID  - info:doi/10.2196/40529
ER  -