The YourMove Study: Optimizing Individualized and Adaptive mHealth Interventions Via Control Systems Engineering Methods

Objectively measured weight in kilograms.

Weight and height will be combined to report BMI in kg/m^2.

Weight and height will be combined to report BMI in kg/m^2.

Waist and hip circumference will be combined to report waist-to-hip ratio in cm/cm.

Total body body composition (fat mass, including a rating of visceral adipose tissue, lean mass, and body water) measured with Bioelectric Impedance Analysis (BIA).

Measured with Bioelectric Impedance Analysis (BIA).

Systolic blood pressure in mmHg.

Diastolic blood pressure in mmHg.

Sit and reach test.

Grip strength of the right and left hands in kilograms with a dynamometer.

Measured using Fitbit.

Assessed through self-report using the Global Physical Activity Questionnaire. The questionnaire is comprised of 16 questions related to physical activity in three settings that include activity at work, travel to and from places, and recreational activities, in addition to sedentary behavior. Metabolic Equivalent (MET) values are assigned to time variables according to intensity of activity, moderate or vigorous, reported in each of the settings. MET values are then used to calculate total physical activity.

Measured using Fitbit.

Measured using Fitbit.

Measured using Fitbit.

Assessed through self-report using a modified Pittsburg Sleep Quality Index questionnaire. Participants respond to questions related to sleep duration and how often they have difficulty falling asleep and staying awake, do not get enough rest. A higher score indicates more restful sleep.

Measured by research assistant.

Measured using a waist-worn tri-axial accelerometer.

Assessed using the Last 7 Day Sedentary Behavior Questionnaire (SIT-Q-7d), which assesses sitting or lying down in five domains (meals, transportation, occupation, non-occupational screen time, and other sedentary time), thus facilitating the calculation of domain-specific and total sedentary time. Frequency within the last 30 days is assessed on a 5-point response scale, ranging from "never or hardly ever" to "always or almost always".

Physical Activity: Change Strategies survey consists of 15-items that assess how often participants engage in strategies that help them change their physical activity in the past month using a 5-point response scale ranging from "Never" to "Many times".

Physical Activity Neighborhood Environment survey consists of 17-items that assess the environmental factors for walking and bicycling in various neighborhoods. Higher values from the scale indicate greater environmental support for physical activity.

Assessed using the Physical Activity and Social Support Scale which consists of 20-items scale based in five forms of social support - companionship, emotional, instrumental, informational, and validation for physical activity. Participants respond to items on a 7-point Likert scale ranging from "never" to "always", or "not applicable". A higher score indicates individuals who are seeking to change exercise behaviors feel a high level of support from friends and family.

Assessed using the Center for Epidemiologic Studies depression scale which consists of 10-items. Participants respond to items related to how they feel and behave on a 5-point response scale ranging from "Rarely or none of the time" to "All of the time". A score equal to or above 10 is considered depressed.

Assessed using the short-form of the state scale of the Spielberger State Trait Anxiety Inventory which consists of 6 items. Participants respond to items related to how they feel on a 4-point response scale ranging from "Not at all" to "Very much".

Assessed using the Rosenberg Self-esteem Scale which consists of 10-items. Participants respond to items related to items related to global self-worth on a 4-point Likert scale ranging from "strongly agree" to "strongly disagree". Higher scores indicate higher self-esteem.

Assessed using the Quality of Well-being survey, self-administered version which consists of 71 items. Participants respond to items related to health status and overall well-being over the previous 3 days. Scores are translated to quality-adjusted life years.

Measured using the 25-ft walk test

Measured using 5x sit-to-stand test which has participants stand up and sit down as quickly as possible 5 times from a straight-backed chair. Only assessed in participants 50 and older.

Assessed with feet in three different positions for 20 seconds each position (feet side by side, feet semi-tandem, and feet full-tandem). All balance testing will be measured using BtrackS balance tracking system, a computerized force plate that will provide a more objective and detailed assessment of balance than administrator observation alone, including total sway measured in centimeters. Only assessed in participants 50 and older.

Participants will be instructed to stand up from a chair, walk around a cone set up 10 feet away, and return to sit in the chair. Only assessed in participants 50 and older.

Assessed using a sub-maximal graded exercise test. A treadmill walking protocol at a participant-selected speed with elevation increases every 2 minutes will be employed until the participant reaches 85% of age predicted maximal heart rate (220 bpm - age) or volitional fatigue, whichever occurs first.