Gamifying accelerometer use increases physical activity levels of individuals pre-disposed to type II diabetes.

Physical activity is important for preventing obesity and diabetes, but most obese and pre-diabetic patients are not physically active. We developed a Fitbit-based game called MapTrek that promotes walking. We recruited obese and pre-diabetic patients. Half were randomly assigned to the control group and given a Fitbit alone. The others were given a Fitbit plus MapTrek. The MapTrek group participated in 6 months of weekly virtual races. Each week, participants were placed in a race with 9 others who achieved a similar number of steps in the previous week's race. Participants moved along the virtual route by the steps recorded on their Fitbit and received daily walking challenges via text message. Text messages also had links to the race map and leaderboard. We used a Bayesian mixed effects model to analyze the number of steps taken during the intervention. A total of 192 (89%) participants in the control group and 196 (91%) in the MapTrek group were included in the analyses. MapTrek significantly increased step counts when it began: MapTrek participants walked almost 1,700 steps more than the control group on the first day of the intervention. We estimate that there is a 97% probability that the effect of MapTrek is at least 1,000 additional steps per day throughout the course of the 6-month intervention and that MapTrek participants would have walked an additional 81 miles, on average, before the effect ended. Our MapTrek intervention led to significant extra walking by the MapTrek participants.

Multilevel mHealth Intervention Increases Physical Activity of Older Adults Living in Retirement Community.

BACKGROUND: Regular physical activity is crucial for healthy aging, but older adults are the least active age group. This study explored the feasibility, acceptability, and efficacy of a multilevel mHealth intervention for increasing physical activity of older adults living in a retirement community. METHODS: Participants included 54 older adults (mean age = 81.2 y, 77.8% female, 98.1% white) living in a retirement community. Participants received a Fitbit Zip and access to a multilevel mHealth physical activity intervention (MapTrek Residential) for 8 weeks. Physical activity (in steps per day) and intervention compliance (days worn) were measured objectively with the Fitbit for 12 weeks (8-wk intervention plus 4-wk follow-up). Psychosocial outcomes (social support, self-efficacy, and outcome expectations) were assessed at baseline and 8 weeks. Acceptability outcomes were assessed with an open-ended process evaluation survey and focus groups. Descriptive statistics and linear mixed models were used to examine intervention effects. RESULTS: Participants increased daily steps from 5438 steps per day at baseline (95% CI, 4620 to 6256) to 6201 steps per day (95% CI, 5359 to 7042) at week 8 (P < .0001) but this was not maintained at 12 weeks (P = .92). CONCLUSIONS: Our multilevel mHealth physical activity intervention was effective for increasing physical activity older adults over 8 weeks. Additional research focused on maintaining physical activity gains with this approach is warranted.

Gamifying Accelerometer Use Increases Physical Activity Levels of Sedentary Office Workers.

BACKGROUND: Sedentary work is hazardous. Over 80% of all US jobs are predominantly sedentary, placing full-time office workers at increased risk for cardiovascular and metabolic morbidity and mortality. Thus, there is a critical need for effective workplace physical activity interventions. MapTrek is a mobile health platform that gamifies Fitbit use for the purpose of promoting physical activity. The purpose of this study was to test the efficacy of MapTrek for increasing daily steps and moderate-intensity steps over 10 weeks in a sample of sedentary office workers. METHODS AND RESULTS: Participants included 146 full-time sedentary office workers aged 21 to 65 who reported sitting at least 75% of their workday. Each participant received a Fitbit Zip to wear daily throughout the intervention. Participants were randomized to either a: (1) Fitbit-only group or 2) Fitbit + MapTrek group. Physical activity outcomes and intervention compliance were measured with the Fitbit activity monitor. The Fitbit + MapTrek group significantly increased daily steps (+2092 steps per day) and active minutes (+11.2 min/day) compared to the Fitbit-only arm, but, on average, participants' steps declined during the study period. CONCLUSIONS: MapTrek is an effective approach for increasing physical activity at a clinically meaningful level in sedentary office workers, but as with accelerometer use alone, the effect decreases over time. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT03109535.

The effect of automated text messaging and goal setting on pedometer adherence and physical activity in patients with diabetes: A randomized controlled trial.

INTRODUCTION: Activity-monitoring devices may increase activity, but their effectiveness in sedentary, diseased, and less-motivated populations is unknown. METHODS: Subjects with diabetes or pre-diabetes were given a Fitbit and randomized into three groups: Fitbit only, Fitbit with reminders, and Fitbit with both reminders and goal setting. Subjects in the reminders group were sent text-message reminders to wear their Fitbit. The goal-setting group was sent a daily text message asking for a step goal. All subjects had three in-person visits (baseline, 3 and 6 months). We modelled daily steps and goal setting using linear mixed-effects models. RESULTS: 138 subjects participated with 48 in the Fitbit-only, 44 in the reminders, and 46 in the goal-setting groups. Daily steps decreased for all groups during the study. Average daily steps were 7123, 6906, and 6854 for the Fitbit-only, the goal-setting, and the reminders groups, respectively. The reminders group was 17.2 percentage points more likely to wear their Fitbit than the Fitbit-only group. Setting a goal was associated with a significant increase of 791 daily steps, but setting more goals did not lead to step increases. CONCLUSION: In a population of patients with diabetes or pre-diabetes, individualized reminders to wear their Fitbit and elicit personal step goals did not lead to increases in daily steps, although daily steps were higher on days when goals were set. Our intervention improved engagement and data collection, important goals for activity surveillance. This study demonstrates that new, more-effective interventions for increasing activity in patients with pre-diabetes and diabetes are needed.

Using Computer Vision and Depth Sensing to Measure Healthcare Worker-Patient Contacts and Personal Protective Equipment Adherence Within Hospital Rooms.

Background. We determined the feasibility of using computer vision and depth sensing to detect healthcare worker (HCW)-patient contacts to estimate both hand hygiene (HH) opportunities and personal protective equipment (PPE) adherence. Methods. We used multiple Microsoft Kinects to track the 3-dimensional movement of HCWs and their hands within hospital rooms. We applied computer vision techniques to recognize and determine the position of fiducial markers attached to the patient's bed to determine the location of the HCW's hands with respect to the bed. To measure our system's ability to detect HCW-patient contacts, we counted each time a HCW's hands entered a virtual rectangular box aligned with a patient bed. To measure PPE adherence, we identified the hands, torso, and face of each HCW on room entry, determined the color of each body area, and compared it with the color of gloves, gowns, and face masks. We independently examined a ground truth video recording and compared it with our system's results. Results. Overall, for touch detection, the sensitivity was 99.7%, with a positive predictive value of 98.7%. For gowned entrances, sensitivity was 100.0% and specificity was 98.15%. For masked entrances, sensitivity was 100.0% and specificity was 98.75%; for gloved entrances, the sensitivity was 86.21% and specificity was 98.28%. Conclusions. Using computer vision and depth sensing, we can estimate potential HH opportunities at the bedside and also estimate adherence to PPE. Our fine-grained estimates of how and how often HCWs interact directly with patients can inform a wide range of patient-safety research.

How children and adults learn to intercept moving gaps.

We used an immersive virtual environment to examine how children and adults learn to intercept moving gaps and whether children and adults benefit from variability of practice. Children (10- and 12-year-olds) and adults attempted to bicycle between two moving vehicle-size blocks without stopping. In Experiment 1, block motions were timed such that if participants maintained a constant speed, they would intercept the gap between the blocks. By the last set of intersections, adults learned to maintain a constant speed throughout the approach to the intersection, 12-year-olds exhibited less variability in time-to-spare when they intercepted the blocks, and 10-year-olds exhibited no significant change across intersection sets. In Experiment 2, block motions during the first eight intersections were timed such that participants needed to either speed up or slow down on all intersections or needed to speed up on half and slow down on half of the intersections. On the last four intersections, all age groups encountered a novel block timing in which no adjustment in speed was necessary to intercept the blocks. The adults performed well regardless of whether they experienced consistent or variable block timings. The 10-year-olds in the variable condition performed better on slow-down trials than their peers in the slow-down condition but performed worse on speed-up trials than their peers in the speed-up condition. Discussion focuses on possible developmental changes in reliance on perceptually available and remembered information in complex perception-action tasks.

Manipulating perception versus action in recalibration tasks.

We conducted six experiments to examine how manipulating perception versus action affects perception-action recalibration in real and imagined blindfolded walking tasks. Participants first performed a distance estimation task (pretest) and then walked through an immersive virtual environment on a treadmill for 10 min. Participants then repeated the distance estimation task (posttest), the results of which were compared with their pretest performance. In Experiments 1a, 2a, and 3a, participants walked at a normal speed during recalibration, but the rate of visual motion was either twice as fast or half as fast as the participants' walking speed. In Experiments 1b, 2b, and 3b, the rate of visual motion was kept constant, but participants walked at either a faster or a slower speed. During pre- and posttest, we used either a blindfolded walking distance estimation task or an imagined walking distance estimation task. Additionally, participants performed the pretest and posttest distance estimation tasks in either the real environment or the virtual environment. With blindfolded walking as the distance estimation task for pre- and posttest, we found a recalibration effect when either the rate of visual motion or the walking speed was manipulated during the recalibration phase. With imagined walking as the distance estimation task, we found a recalibration effect when the rate of visual motion was manipulated, but not when the walking speed was manipulated in both the real environment and the virtual environment. Discussion focuses on how spatial-updating processes operate on perception and action and on representation and action.

Preadolescent temperament and risky behavior: bicycling across traffic-filled intersections in a virtual environment.

OBJECTIVE: This investigation used a bicycling simulator to examine how preadolescent temperament is related to risky behavior. METHODS: Children aged 10 and 12 years (N = 109) rode a bicycle through a virtual environment where they crossed intersections with continuous cross traffic. Mothers filled out the Early Adolescent Temperament Questionnaire-Revised. RESULTS: Older children and male participants timed their entry into the intersection more precisely than did younger children and female participants, as did 10-year-old children higher in inhibitory control and 10-year-old boys higher in aggression. However, only 10-year-old children higher in inhibitory control had more time to spare when they cleared the intersection. For 10-year-old boys higher in aggression, cutting in more closely behind the lead vehicle was accompanied by less stopping at intersections, less waiting before crossing, and choosing smaller gaps to cross. CONCLUSIONS: The Discussion section focuses on inhibitory control as a protective factor and aggression as a risk factor for car-bicycle collisions.

Perceiving and acting on complex affordances: how children and adults bicycle across two lanes of opposing traffic.

This investigation examined how children and adults negotiate a challenging perceptual-motor problem with significant real-world implications--bicycling across two lanes of opposing traffic. Twelve- and 14-year-olds and adults rode a bicycling simulator through an immersive virtual environment. Participants crossed intersections with continuous cross traffic coming from opposing directions. Opportunities for crossing were divided into aligned (far gap opens with or before near gap) and rolling (far gap opens after near gap) gap pairs. Children and adults preferred rolling to aligned gap pairs, though this preference was stronger for adults than for children. Crossing aligned versus rolling gap pairs produced substantial differences in direction of travel, speed of crossing, and timing of entry into the near and far lanes. For both aligned and rolling gap pairs, children demonstrated less skill than adults in coordinating self and object movement. These findings have implications for understanding perception-action-cognition links and for understanding risk factors underlying car-bicycle collisions.

Changes in children's perception-action tuning over short time scales: bicycling across traffic-filled intersections in a virtual environment.

This investigation examined short-term changes in child and adult cyclists' gap decisions and movement timing in response to general and specific road-crossing experiences. Children (10- and 12-year-olds) and adults rode a bicycle through a virtual environment with 12 intersections. Participants faced continuous cross traffic and waited for gaps they judged were adequate for crossing. In the control condition, participants encountered randomly ordered gaps ranging from 1.5 to 5.0s at all intersections. In the high-density condition, participants encountered high-density intersections sandwiched between sets of control intersections. These high-density intersections were designed to push participants toward taking tighter gaps. Participants in both conditions were more likely to accept 3.5-, 4.0-, 4.5-, and 5.0-s gaps at the last set of intersections than at the first set of intersections, whereas participants in the high-density condition were also more likely to accept very tight 3.0-s gaps at the last intersections than at the first intersections. Moreover, individuals in the high-density condition who waited less and took shorter gaps at the middle intersections were also more likely to take very tight 3.0-s gaps at the last intersections. The 10-year-olds in both conditions had more time to spare when they cleared the path of the oncoming car at the last intersections, whereas the 12-year-olds and adults showed no change in time to spare across intersections. The discussion focuses on linking short-term change in perceptual-motor functioning to longer term perceptual-motor development.

An immersive virtual peer for studying social influences on child cyclists' road-crossing behavior.

The goal of our work is to develop a programmatically controlled peer to bicycle with a human subject for the purpose of studying how social interactions influence road-crossing behavior. The peer is controlled through a combination of reactive controllers that determine the gross motion of the virtual bicycle, action-based controllers that animate the virtual bicyclist and generate verbal behaviors, and a keyboard interface that allows an experimenter to initiate the virtual bicyclist's actions during the course of an experiment. The virtual bicyclist's repertoire of behaviors includes road following, riding alongside the human rider, stopping at intersections, and crossing intersections through specified gaps in traffic. The virtual cyclist engages the human subject through gaze, gesture, and verbal interactions. We describe the structure of the behavior code and report the results of a study examining how 10- and 12-year-old children interact with a peer cyclist that makes either risky or safe choices in selecting gaps in traffic. Results of our study revealed that children who rode with a risky peer were more likely to cross intermediate-sized gaps than children who rode with a safe peer. In addition, children were significantly less likely to stop at the last six intersections after the experience of riding with the risky than the safe peer during the first six intersections. The results of the study and children's reactions to the virtual peer indicate that our virtual peer framework is a promising platform for future behavioral studies of peer influences on children's bicycle riding behavior.

Synchronizing self and object movement: how child and adult cyclists intercept moving gaps in a virtual environment.

Two experiments examined how 10- and 12-year-old children and adults intercept moving gaps while bicycling in an immersive virtual environment. Participants rode an actual bicycle along a virtual roadway. At 12 test intersections, participants attempted to pass through a gap between 2 moving, car-sized blocks without stopping. The blocks were timed such that it was sometimes necessary for participants to adjust their speed in order to pass through the gap. We manipulated available visual information by presenting the target blocks in isolation in Experiment 1 and in streams of blocks in Experiment 2. In both experiments, adults had more time to spare than did children. Both groups had more time to spare when they were required to slow down than when they were required to speed up. Participants' behavior revealed a multistage interception strategy that cannot be explained by the use of a monotonic control law such as the constant bearing angle strategy. The General Discussion section focuses on possible sources of changes in perception-action coupling over development and on task-specific constraints that could underlie the observed interception strategy.

Estimating distance in real and virtual environments: Does order make a difference?

In this investigation, we examined how the order in which people experience real and virtual environments influences their distance estimates. Participants made two sets of distance estimates in one of the following conditions: (1) real environment first, virtual environment second; (2) virtual environment first, real environment second; (3) real environment first, real environment second; or (4) virtual environment first, virtual environment second. In Experiment 1, the participants imagined how long it would take to walk to targets in real and virtual environments. The participants' first estimates were significantly more accurate in the real than in the virtual environment. When the second environment was the same as the first environment (real-real and virtual-virtual), the participants' second estimates were also more accurate in the real than in the virtual environment. When the second environment differed from the first environment (real-virtual and virtual-real), however, the participants' second estimates did not differ significantly across the two environments. A second experiment, in which the participants walked blindfolded to targets in the real environment and imagined how long it would take to walk to targets in the virtual environment, replicated these results. These subtle yet persistent order effects suggest that memory can play an important role in distance perception.

Children's Road Crossing: A Window Into Perceptual-Motor Development.

Most research on perceptual-motor development has focused on changes occurring during infancy and toddlerhood. In this paper, we describe our work on the development of perceptual-motor development during late childhood and early adolescence in the context of an important applied problem: bicycling across traffic-filled roads. Specifically, we have examined the gaps between cars that children and adults accept when bicycling across intersections, using an immersive, interactive bicycling simulator. This work highlights both methodological advances in using immersive, interactive virtual environments to study perceptual-motor functioning as well as theoretical advances in understanding the problem of moving the self in relation to other moving objects. We conclude with ideas for future research and practical implications of this work.

Children's perception of gap affordances: bicycling across traffic-filled intersections in an immersive virtual environment.

This study examined gap choices and crossing behavior in children and adults using an immersive, interactive bicycling simulator. Ten- and 12-year-olds and adults rode a bicycle mounted on a stationary trainer through a virtual environment consisting of a street with 6 intersections. Participants faced continuous cross traffic traveling at 25 mph or 35 mph and waited for gaps they judged were adequate for crossing. Children and adults chose the same size temporal gaps, but children left far less time to spare between themselves and the approaching vehicle when they crossed the intersection. Relative to adults, children delayed in getting started and took longer to reach the roadway. Discussion focuses on developmental changes in how children coordinate self movement with object movement.