Wearable Activity Monitor Research Articles

Raw Photoplethysmography as an Enhancement for Research-Grade Wearable Activity Monitors.

Wearable monitors continue to play a critical role in scientific assessments of physical activity. Recently, research-grade monitors have begun providing raw data from photoplethysmography (PPG) alongside standard raw data from inertial sensors (accelerometers and gyroscopes). Raw PPG enables granular and transparent estimation of cardiovascular parameters such as heart rate, thus presenting a valuable alternative to standard PPG methodologies (most of which rely on consumer-grade monitors that provide only coarse output from proprietary algorithms). The implications for physical activity assessment are tremendous, since it is now feasible to monitor granular and concurrent trends in both movement and cardiovascular physiology using a single noninvasive device. However, new users must also be aware of challenges and limitations that accompany the use of raw PPG data. This viewpoint paper therefore orients new users to the opportunities and challenges of raw PPG data by presenting its mechanics, pitfalls, and availability, as well as its parallels and synergies with inertial sensors. This includes discussion of specific applications to the prediction of energy expenditure, activity type, and 24-hour movement behaviors, with an emphasis on areas in which raw PPG data may help resolve known issues with inertial sensing (eg, measurement during cycling activities). We also discuss how the impact of raw PPG data can be maximized through the use of open-source tools when developing and disseminating new methods, similar to current standards for raw accelerometer and gyroscope data. Collectively, our comments show the strong potential of raw PPG data to enhance the use of research-grade wearable activity monitors in science over the coming years.

A social media game to increase physical activity among older adult women: protocol of a randomized controlled trial to evaluate CHALLENGE

BackgroundOlder adult women often do not engage in sufficient physical activity (PA) and can encounter biological changes that exacerbate the negative effects of inadequate activity. Wearable activity monitors can facilitate PA initiation, but evidence of sustained behavior change is lacking. Supplementing wearable technologies with intervention content that evokes enjoyment, interest, meaning, and personal values associated with PA may support long term adherence. In this paper, we present the protocol of an NIA-funded study designed to evaluate the efficacy of CHALLENGE for increasing step count and motivation for PA in insufficiently active older women (Challenges for Healthy Aging: Leveraging Limits for Engaging Networked Game-based Exercise). CHALLENGE uses social media to supplement wearable activity monitors with the autonomy-supportive frame of a game. We hypothesize that CHALLENGE will engender playful experiences that will improve motivation for exercise and lead to sustained increases in step count.MethodsWe will recruit 300 healthy, community dwelling older adult women on a rolling basis and randomize them to receive either the CHALLENGE intervention (experimental arm) or an activity monitor-only intervention (comparison arm). Participants in both groups will receive a wearable activity monitor and personalized weekly feedback emails. In the experimental group, participants will also be added to a private Facebook group, where study staff will post weekly challenges that are designed to elicit playful experiences while walking. Assessments at baseline and 6, 12, and 18 months will measure PA and motivation-related constructs. We will fit linear mixed-effects models to evaluate differences in step count and motivational constructs, and longitudinal mediation models to evaluate if interventional effects are mediated by changes in motivation. We will also conduct thematic content analysis of text and photos posted to Facebook and transcripts from individual interviews.DiscussionBy taking part in a year-long intervention centered on imbuing walking behaviors with playful and celebratory experiences, participating older adult women may internalize changes to their identity and relationship with PA that facilitate sustained behavior change. Study results will have implications for how we can harness powerful and increasingly ubiquitous technologies for health promotion to the vast and growing population of older adults in the U.S. and abroad.Trial registrationClinicalTrials.gov Identifier NCT04095923. Registered September 17th, 2019.

Exercise Therapy to Reduce Anxiety (ExTRA) in mid-life and later-life adults: study protocol

BackgroundAnxiety in mid-life and later-life is highly prevalent and causes significant distress and disability. There is increasing evidence supporting the potential effectiveness of exercise interventions for reducing clinically significant anxiety. Self-directed online interventions can be scalable and thus reach more people. AimsThe Exercise Therapy to Reduce Anxiety (ExTRA) project aims to assess the feasibility and acceptability of an 8-week web-based exercise intervention with the innovation of being self-directed, and facilitated by wearable activity monitors (WAMs) and tailored behaviour change strategies to reduce anxiety in mid-life and later-life adults with clinically significant anxiety. MethodsExTRA will recruit 20-30 community dwelling adults aged 40-79 years with clinically significant anxiety. The self-directed 8-week web-based exercise intervention includes information and strategies to support participants to meet Australian national physical activity guidelines. The intervention is adapted from previous face-to-face trials and includes strategies to support participants living with anxiety. Feasibility will be measured by screening and retention rates. Acceptability will be measured by website usage data, online outcome measure completion, and an evaluation questionnaire. Other outcome measures include anxiety measured by the Depression Anxiety Stress Scales, and physical activity measured by the Global Physical Activity Questionnaire and a WAM. ResultsFindings will demonstrate whether this intervention is feasible and acceptable, and provide preliminary efficacy data. ConclusionsThe findings of this pragmatic real-world study will be valuable in guiding development of future trials, including randomised controlled trials of scalable and accessible exercise interventions to reduce the distress, disability and cost of anxiety.

Physical Functioning, Physical Activity, and Variability in Gait Performance during the Six-Minute Walk Test.

Instrumenting the six-minute walk test (6MWT) adds information about gait quality and insight into fall risk. Being physically active and preserving multi-directional stepping abilities are also important for fall risk reduction. This analysis investigated the relationship of gait quality during the 6MWT with physical functioning and physical activity. Twenty-one veterans (62.2 ± 6.4 years) completed the four square step test (FSST) multi-directional stepping assessment, a gait speed assessment, health questionnaires, and the accelerometer-instrumented 6MWT. An activity monitor worn at home captured free-living physical activity. Gait measures were not significantly different between minutes of the 6MWT. However, participants with greater increases in stride time (ρ = -0.594, p < 0.01) and stance time (ρ = -0.679, p < 0.01) during the 6MWT reported lower physical functioning. Neither physical activity nor sedentary time were related to 6MWT gait quality. Participants exploring a larger range in stride time variability (ρ = 0.614, p < 0.01) and stance time variability (ρ = 0.498, p < 0.05) during the 6MWT required more time to complete the FSST. Participants needing at least 15 s to complete the FSST meaningfully differed from those completing the FSST more quickly on all gait measures studied. Instrumenting the 6MWT helps detect ranges of gait performance and provides insight into functional limitations missed with uninstrumented administration. Established FSST cut points identify aging adults with poorer gait quality.

Highlighting Unseen Activity Through 48-Hour Continuous Measurement in Subacute Stroke Rehabilitation: Preliminary Cohort Study.

Motor impairments not only lead to a significant reduction in patient activity levels but also trigger a further deterioration in motor function due to deconditioning, which is an issue that is particularly pronounced during hospitalization. This deconditioning can be countered by sustaining appropriate activity levels. Activities that occur outside of scheduled programs, often overlooked, are critical in this context. Wearable technology, such as smart clothing, provides a means to monitor these activities. This study aimed to observe activity levels in patients who had strokes during the subacute phase, focusing on both scheduled training sessions and other nontraining times in an inpatient rehabilitation environment. A smart clothing system is used to simultaneously measure heart rate and acceleration, offering insights into both the amount and intensity of the physical activity. In this preliminary cohort study, 11 individuals undergoing subacute stroke rehabilitation were enrolled. The 48-hour continuous measurement system, deployed at admission and reassessed 4 weeks later, monitored accelerometry data for physical activity (quantified with a moving SD of acceleration [MSDA]) and heart rate for intensity (quantified with percent heart rate reserve). The measurements were performed using a wearable activity monitoring system, the hitoe (NTT Corporation and Toray Industries, Inc) system comprising a measuring garment (wear or strap) with integrated electrodes, a data transmitter, and a smartphone. The Functional Independence Measure was used to assess the patients' daily activity levels. This study explored factors such as differences in activity during training and nontraining periods, correlations with activities of daily living (ADLs) and age, and changes observed after 4 weeks. A significant increase was found in the daily total MSDA after the 4-week program, with the average percent heart rate reserve remaining consistent. Physical activity during training positively correlated with ADL levels both at admission (ρ=0.86, P<.001) and 4 weeks post admission (ρ=0.96, P<.001), whereas the correlation between age and MSDA was not significant during training periods at admission (ρ=-0.41, P=.21) or 4 weeks post admission (ρ=-0.25, P=.45). Conversely, nontraining activity showed a negative correlation with age, with significant negative correlations with age at admission (ρ=-0.82, P=.002) and 4 weeks post admission (ρ=-0.73, P=.01). Inpatient rehabilitation activity levels were positively correlated with ADL levels. Further analysis revealed a strong positive correlation between scheduled training activities and ADL levels, whereas nontraining activities showed no such correlation. Instead, a negative correlation between nontraining activities and age was observed. These observations suggest the importance of providing activity opportunities for older patients, while it may also suggest the need for adjusting the activity amount to accommodate the potentially limited fitness levels of this demographic. Future studies with larger patient groups are warranted to validate and further elucidate these findings.

Fabrication of multi-sensory Ti3C2Tx MXene/Nylon 6 composite fibers via interfacial deposition method

Here, we present a composite material in the form of Ti3C2Tx MXene/nylon 6 (MPA6) core-shell fibers. These fibers were synthesized through a process involving the systematic stacking of Ti3C2Tx MXene nanosheets to form a continuous film via interfacial self-assembly, followed by coating onto the surface of nylon 6 fibers. Notably, despite a minimal MXene coating of just 1.53 wt%, the MPA6 fibers exhibit remarkable electrical conductivity, reaching 11.39 ± 2.51 S/cm. The interwoven conductive network within the fabric's fibers contributes to its exceptional properties, including rapid response time (with a response time of 63 ms during pressing behavior), fatigue resistance (maintaining a stable response over 300 cycles), and consistent reproducibility of response during repeated cycles. With its increased sensitivity to various human activities, this composite fiber is well-suited for use as a wearable personal activity monitor. Additionally, its exceptional sensitivity to gravitational objects makes it a valuable tool for gravity detection, capable of detecting changes as small as 1 g.

Using an mHealth approach to collect patient-generated health data for predicting adverse health outcomes among adult survivors of childhood cancer.

Cancer therapies predispose childhood cancer survivors to various treatment-related late effects, which contribute to a higher symptom burden, chronic health conditions (CHCs), and premature mortality. Regular monitoring of symptoms between clinic visits is useful for timely medical consultation and interventions that can improve quality of life (QOL). The Health Share Study aims to utilize mHealth to collect patient-generated health data (PGHD; daily symptoms, momentary physical health status) and develop survivor-specific risk prediction scores for mitigating adverse health outcomes including poor QOL and emergency room admissions. These personalized risk scores will be integrated into the hospital-based electronic health record (EHR) system to facilitate clinician communications with survivors for timely management of late effects. This prospective study will recruit 600 adult survivors of childhood cancer from the St. Jude Lifetime Cohort study. Data collection include 20 daily symptoms via a smartphone, objective physical health data (physical activity intensity, sleep performance, and biometric data including resting heart rate, heart rate variability, oxygen saturation, and physical stress) via a wearable activity monitor, patient-reported outcomes (poor QOL, unplanned healthcare utilization) via a smartphone, and clinically ascertained outcomes (physical performance deficits, onset of/worsening CHCs) assessed in the survivorship clinic. Participants will complete health surveys and physical/functional assessments in the clinic at baseline, 2) report daily symptoms, wear an activity monitor, measure blood pressure at home over 4 months, and 3) complete health surveys and physical/functional assessments in the clinic 1 and 2 years from the baseline. Socio-demographic and clinical data abstracted from the EHR will be included in the analysis. We will invite 20 cancer survivors to investigate suitable formats to display predicted risk information on a dashboard and 10 clinicians to suggest evidence-based risk management strategies for adverse health outcomes. Machine and statistical learning will be used in prediction modeling. Both approaches can handle a large number of predictors, including longitudinal patterns of daily symptoms/other PGHD, along with cancer treatments and socio-demographics. The individualized risk prediction scores and added communications between providers and survivors have the potential to improve survivorship care and outcomes by identifying early clinical presentations of adverse events.

THE EFFECT OF INTRA-INFUSION EXERCISE ON CHEMOTHERAPY SIDE EFFECTS; AN INTERIM ANALYSIS

INTRODUCTION Chemotherapy treatment results in side effects that impact quality of life and physical activity behaviours. Aerobic exercise in parallel with chemotherapy reduces side effects particularly fatigue and improves quality of life. Our recent clinical pilot work has shown that an acute bout of aerobic exercise increases blood flow to tumours. Therefore, if exercise is performed during chemotherapy (intra-infusion exercise), the result may be increased drug delivery and treatment efficacy. Intra-infusion exercise also provides a supervised opportunity to overcome patient-reported barriers to exercise during a period where a patient would be otherwise sedentary. AIM: The aim of this ongoing randomised controlled trial is to determine the effects of aerobic intra-infusion exercise on chemotherapy side effects and physical activity behaviours. METHODS Adults under 75 years receiving chemotherapy with stage I-III breast, colorectal or ovarian cancer, and ECOG 0-2 were eligible. Four chemotherapy sessions were included, cycle 1 (C1) a baseline and cycles 2-4 (C2-4) included exercise intervention or usual care. The exercise task was 20-minutes of moderate intensity cycling (40-50% heart rate reserve) during infusion. All participants received exercise education. A 7-day symptom diary (including Brief Fatigue Inventory (BFI) and Edmonton Symptom Assessment System (ESAS)) was completed following C1-C4 and an activity monitor worn. RESULTS Nineteen participants have completed the trial (79% female), with no adverse events reported in either group. Physical symptoms increased across cycles in both groups (p=0.003). 1-week mean ESAS physical symptoms total in the exercise group (C1 16±9.8, C4 23±13.7) and control group (C1 18±7.1, C4 23±12.7) were similar. No significant effects were seen for fatigue or step count. CONCLUSION Intra-infusion exercise is safe and does not increase side effects in patients receiving chemotherapy. Expected increases in physical symptoms were observed without difference between usual care and exercise. Further analysis with ongoing recruitment will continue to examine any differences between groups.

Quantifying postoperative recovery using wearable activity monitors following abdominal wall surgery: The AbTech trial

PurposeThis work aimed to investigate the validity of wearable activity monitors (WAMs) as an objective tool to measure the return toward normal functional mobility following abdominal wall surgery. This was achieved by quantifying and comparing pre- and postoperative physical activity (PA). MethodsA multicenter, prospective, observational cohort study was designed. Patients undergoing abdominal wall surgery were assessed for eligibility and consent for study participation was obtained. Participants were asked to wear a WAM (AX3, Axivity) on the wrist of their dominant hand at least 48 hours pre-operatively, for up to 2 weeks postop, and again after 6 months postop for 48 hours. ResultsA cohort of 20 patients were recruited in this validation study with a mean age of 47.3 ± 13.0 years. Postoperation, the percentage median PA (±IQR) dropped to 32.6% (20.1), whereas on day 14, PA had reached 64.6% (22.7) of the preoperative value providing construct validity. Activity levels at >6 months postop increased by 16.4% on an average when compared to baseline preoperative PA (p = 0.046). ConclusionThis study demonstrates that WAMs are valid markers of postoperative recovery following abdominal wall surgery. This was achieved by quantifying the reduction in PA postoperation, which has not been previously shown. In addition, this study suggests that abdominal wall surgery may improve the patient’s quality of life via increased functional mobility at 6 months postop. In the future, this technology could be used to identify the patient and surgical factors that are predictors of outcome following abdominal wall surgery.

COVID-19 Stay-at-home mandates impacts daily ambulatory bout intensity and duration in elementary school-aged children: A wearable sensor based analysis

IntroductionSARS COVID-19 pandemic resulted in major changes to how daily life was conducted. Health officials instituted policies to decelerate the spread of the virus, resulting in changes in physical activity patterns of school-aged children. The aim of this study was to utilize a wearable activity monitor to assess ambulatory activity in elementary-school aged children in their home environment during a COVID-19 Stay-at-Home mandate. MethodsThis institutional review board approved research study was performed between April 3rd – May 1st of 2020 during which health officials issued several stay-at-home (shelter-in-place) orders. Participant recruitment was conducted using a convenience sample of 38 typically developing children. Participants wore a StepWatch Activity Monitor for one week and data were downloaded and analyzed to assess global ambulatory activity measures along with ambulatory bout intensity/duration. For comparison purposes, SAM data collected before the pandemic, of a group of 27 age-matched children from the same region of the United States, was included. Statistical analyses were performed comparing SAM variables between children abiding by a stay-at-home mandate (Stay-at-Home) versus the Historical cohort (alpha=0.05). ResultsStay-at-Home cohort took on average 3737 fewer daily total steps compared to the Historical cohort (p<0.001). Daily Total Ambulatory Time (TAT), across all days was significantly lower in the Stay-at-Home cohort compared to the Historical cohort (mean difference: 81.9 minutes, p=0.001). The Stay-at-Home cohort spent a significantly higher percentage of TAT in Easy intensity ambulatory activity (mean difference: 2%, p<0.001) and therefore a significantly lower percentage of TAT in Moderate+ intensity (mean difference: 2%, p<0.001). ConclusionsThe stay-at-home mandates resulted in lower PA levels in elementary school-aged children, beyond global measures to also bout intensity/duration. It appears that in-person school is a major contributor to achieving higher levels of PA and our study provides additional data for policymakers to consider for future decisions.

The sedentary behavior reduction in pregnancy intervention (SPRING) pilot and feasibility randomized trial

Pregnant individuals rarely achieve moderate-to-vigorous intensity physical activity recommendations.Purpose The sedentary behavior reduction in pregnancy intervention (SPRING) pilot and feasibility randomized trial aimed to demonstrate feasibility, acceptability, and initial efficacy of a lower intensity intervention targeting reduced sedentary behavior and increased standing and steps.Methods First trimester pregnant individuals at risk for high sedentary behavior and adverse pregnancy outcomes (APO) were randomized 2:1 to a multi-component sedentary behavior reduction intervention or no-contact control. Intervention components included biweekly remote health coaching, wearable activity monitor, height-adjustable workstation, and a private Facebook group. Evidence-based behavioral targets included sedentary time < 9 h/day, increasing standing by 2–3 h/day, and ≥ 7500 steps/day. Participants completed all-remote assessments (baseline, second trimester, third trimester) of sedentary behavior and activity (thigh-worn activPAL) along with exploratory pregnancy health outcomes abstracted from medical records. Intervention effects vs. control were evaluated using generalized mixed models and an intention-to-treat approach. Intervention participants also provided feedback on perceived benefits and acceptability.Results Participants (34 intervention; 17 control) had mean age 32 years, were 83% White, with mean pre-pregnancy BMI 28 kg/m2. Retention was high (90% and 83% at second and third trimester follow-up visits). Intervention participants decreased sedentary time (-0.84 h/day, p = 0.019) and increased standing (+0.77 h/day, p = 0.003), but did not increase steps/day (+710, p = 0.257) compared to controls. Intervention participants reported many perceived benefits and identified the wearable, height-adjustable workstation, and behavioral lessons as most useful.Conclusion For pregnant individuals at risk for high sedentary behavior and APOs, a sedentary behavior reduction intervention is feasible, acceptable, and may offer a viable alternative to more intense physical activity recommendations during pregnancy. Further testing in a fully powered clinical trial is warranted.Trial registration NCT05093842 on clinicaltrials.gov

Stash: Flexible Energy Storage for Intermittent Sensors

Batteryless sensors promise a sustainable future for sensing, but they face significant challenges when storing and using environmental energy. Incoming energy can fluctuate unpredictably between periods of scarcity and abundance, and device performance depends on both incoming energy and how much a device can store. Existing batteryless devices have used fixed or run-time selectable front-end capacitor banks to meet the energy needs of different tasks. Neither approach adapts well to rapidly changing energy harvesting conditions, nor does it allow devices to store excess energy during times of abundance without sacrificing performance. This article presents Stash, a hardware back-end energy storage technique that allows batteryless devices to charge quickly and store excess energy when it is abundant, extending their operating time and carrying out additional tasks without compromising the main ones. Stash performs like a small capacitor device when small capacitors excel and like a large capacitor device when large capacitors excel, with no additional software complexity and negligible power overhead. We evaluate Stash using two applications—temperature sensing and wearable activity monitoring—under both synthetic solar energy and recorded solar and thermal traces from various human activities. Our results show that Stash increased sensor coverage by up to 15% under variable energy-harvesting conditions when compared to competitor configurations that used fixed small, large, and reconfigurable front-end energy storage.

Standardizing Continuous Physical Activity Monitoring in Patients with Cervical Spondylosis.

Prospective cohort study. To use a commercial wearable device to measure real-life, continuous physical activity in patients with CS and to establish age-adjusted and sex-adjusted standardized scores. Patients with cervical spondylosis (CS) often present with pain or neurologic deficits that result in functional limitations and inactivity. However, little is known regarding the influence of CS on the patient's real-life physical activity. This study included 100 English-speaking adult patients with cervical degenerative diseases undergoing elective spine surgery at Stanford University who owned iPhones. Patients undergoing surgery for spine infections, trauma, tumors, or lumbar degenerative disease were excluded. Activity two weeks before surgery was expressed as raw daily step counts. Standardized z-scores were calculated based on age-specific and sex-specific values of a control population. Responses to patient-reported outcome measures (PROMs) surveys assessed convergent validity. Functional impairment was categorized based on predetermined z-score cut-off values. Thirty CS with a mean (±SD) age of 56.0 (±13.4) y wore an Apple Watch for ≥8 hours/day in 87.1% of the days. The mean watch wear time was 15.7 (±4.2) hours/day, and the mean daily step count was 6400 (±3792). There was no significant difference in activity between 13 patients (43%) with myelopathy and 17 (57%) without myelopathy. Test-retest reliability between wearable step count measurements was excellent (ICC β=0.95). Physical activity showed a moderate positive correlation with 36-Item Short Form Survey Physical Component Summary, EuroQol-5-dimension visual analog scale, and Patient-Reported Outcomes Measurement Information System Physical Function Subscale. Activity performance was classified into categories of "no impairment" [step count=9640 (±2,412)], "mild impairment" [6054(±816)], "moderate impairment" [3,481 (±752)], and "severe impairment" [1,619 (±240)]. CS patients' physical activity is significantly lower than the general population or the frequently stated goals of 7000 to 10,000 steps/day. Standardized, continuous wearable physical activity monitoring in CS is a reliable, valid, and normalized outcome tool that may help characterize functional impairment before and after spinal interventions.

PSX-10 Pilot Study Estimating Energy Expenditure in Dogs Using a Quantified Health Approach Indicates Potential to Improve Estimation of Energy Requirements

Abstract Over 50% of dogs in the USA are overweight or obese indicating that owners find it difficult to know how much food their dog needs. Feeding guidelines are based on the average energy requirements of dogs and do not take into account measured activity levels, which may lead to overfeeding by well-intentioned owners. The most common published energy prediction equation is (RER*AF) where RER is Resting Energy Requirement [70*(BW kg)0.75)] and AF is the Activity Factor, which generally ranges between 1 (body weight loss) and 8 (heavy work). This equation requires the user to estimate activity levels when selecting an AF, which may result in under- or overfeeding. The objective of this pilot study was to determine the ability of collar-worn activity monitors to more accurately predict the energy expenditure of dogs. Ten weight-stable beagles were group-housed at the Hill’s Pet Nutrition Center in Topeka, KS. Dogs were provided daily access to open, outdoor play space and human interaction; water was freely available. Dogs were weighed before feeding on days 1 and 5 of each of the 2 test periods. Accelerometer-based activity monitors were attached to the collars of the dogs on day 1 of each test period and activity was continually measured throughout the study using the activity monitor. Daily food consumption in grams was recorded and was converted to energy intake using the caloric density of the food. Daily energy requirements were calculated for each dog using the standard RER equation and either a standard AF of 1.6 or the estimated energy required for activity, in which newly established algorithms for quantification of walking, trotting, and running behaviors were paired with estimated caloric expenditure based on level of exertion (quantified health approach). The mean absolute error (MAE) of each method was calculated as the absolute value of the difference between the daily energy requirement vs. the daily caloric intake for each dog. The MAE was averaged across all dogs and all days for each of the two methods. The MAE ± SD of the standard RER and AF was 103 ± 126 kcal/day (Range -21.5 to 216 kcal/day). The MAE ± SD of the quantified health approach was 86 ± 90 kcal/day (Range -37.6 to 164.4 kcal/day). Both approaches resulted in normal MAE distributions. In this pilot study, quantifying energy expenditure using a wearable activity monitor reduced over-feeding by 16.5% compared with standard equations. In the future, energy predictions based on measured activity could result in more accurate feeding recommendations than traditional approaches. Future research aimed at optimizing energy predictions may help address the problem of pet obesity. This study was approved by the Hill’s Internal Animal Care and Use Committee. Funding: This study was funded by Hill’s Pet Nutrition, Inc.

Acceptability and Usability of a Theory-Driven Intervention via Email to Promote Physical Activity in Women Who Are Overweight or Obese: Substudy Within a Randomized Controlled Trial.

Insufficient physical activity (PA) and excess weight increase illness risk for women. Face-to-face interventions can increase PA levels; however, they are often inaccessible. With growing interest in digital interventions, a Self-Determination Theory (SDT)-driven intervention was developed and delivered via email to promote PA in women who were insufficiently active and overweight or obese. This substudy explores users' perspectives about the acceptability and usability of the intervention, which was coupled with a wearable activity monitor and PA recommendations. A 3-arm, parallel group, randomized controlled trial (unblinded) was conducted in Ontario, Canada. Recruitment occurred from September 2018 to March 2019 via advertising through social media, web-based boards, and posters in publicly accessible areas. In total, 47 women with a BMI of ≥25 kg/m2 who were not meeting the Canadian PA guidelines were randomly assigned to 1 of 3 arms (arm 1: n=15, 32%; arm 2: n=16, 34%; arm 3: n=16, 34%). This substudy focused on the 15 participants allocated to the main intervention arm. Participants received an automated intervention consisting of (1) 6 weekly emails, (2) a Polar Electro Inc A300 activity monitor (with access to the Polar Flow website and companion smartphone app), and (3) a copy of the Canadian PA guidelines for adults. Emails were developed using SDT and designed to enhance autonomous motivation by fostering the psychological needs of competence, autonomy, and relatedness. Well-established motivational and behavior change techniques were embedded in the emails to promote needs satisfaction. After the intervention (ie, 7 weeks after randomization), participants were invited to complete a web-based acceptability and usability survey containing open-ended and closed-ended questions; responses were analyzed using descriptive and content analyses, respectively. The analyses included data from 93% (14/15) of the women (age: mean 33.4, SD 7.5; range 24-44 years; BMI: mean 31.3, SD 5.8 kg/m2; range 25-40.5 kg/m2) who received the main intervention and completed the postintervention survey. Open-ended responses indicated that participants were generally satisfied with the intervention and appreciated that emails prompted self-reflection, kept them on track and accountable, provided informational support, and were nonpressuring. Furthermore, they suggested that the monitor was "enjoyable" and "helpful"; quantitative data corroborated this, as 71% (10/14) said that the monitor was "very valuable/absolutely valuable," 71% (10/14) would "very probably/definitely" still use one, and 86% (12/14) wore it for ≥5 days per week for ≥8 hours per day and checked it "occasionally/frequently/very frequently." Potential threats to acceptability included "long" and "text-heavy" emails; lack of personal contact; and cumbersome, unaesthetic monitors. Results suggest that this SDT-driven, email-delivered intervention may be an acceptable low-contact approach to promote PA in women who are overweight or obese and insufficiently active; however, improvements are warranted and studies ascertaining its effectiveness are needed. ClinicalTrials.gov NCT03601663; http://clinicaltrials.gov/ct2/show/NCT03601663. RR2-10.1177/20552076221093134.

A Fully Self-Powered Wearable Leg Movement Sensing System for Human Health Monitoring.

Energy-autonomous wearable human activity monitoring is imperative for daily healthcare, benefiting from long-term sustainable uses. Herein, a fully self-powered wearable system, enabling real-time monitoring and assessments of human multimodal health parameters including knee joint movement, metabolic energy, locomotion speed, and skin temperature, which are fully self-powered by highly-efficient flexible thermoelectric generators (f-TEGs) is proposed and developed. The wearable system is composed of f-TEGs, fabric strain sensors, ultra-low-power edge computing, and Bluetooth. The f-TEGs worn on the leg not only harvest energy from body heat and supply power sustainably for the whole monitoring system, but also serve as zero-power motion sensors to detect limb movement and skin temperature. The fabric strain sensor made by printing PEDOT: PSS on pre-stretched nylon fiber-wrapped rubber band enables high-fidelity and ultralow-power measurements on highly-dynamic knee movements. Edge computing is elaborately designed to estimate multimodal health parameters including time-varying metabolic energy in real-time, which are wirelessly transmitted via Bluetooth. The whole monitoring system is operated automatically and intelligently, works sustainably in both static and dynamic states, and is fully self-powered by the f-TEGs.

The Use of Wearable Activity Monitors to Measure Upper Limb Physical Activity After Axillary Lymph Node Dissection and Sentinel Lymph Node Biopsy

BackgroundWe suspect that morbidity from both sentinel lymph node biopsy (SLNB) and axillary lymph node dissection (ALND) has been inadequately evaluated to date. Current methodologies are subjective and susceptible to bias. Objective assessment using wearable activity monitors (WAMs) would allow quantitative analysis of recovery by measuring physical activity (PA) and could provide evidence for axillary de-escalation.Patients and MethodsA prospective, single center, observational study was conducted from February 2020 to May 2022. Consecutive patients undergoing breast and/or reconstructive surgery and axillary surgeries were identified from the operating schedules. Patients wore WAMs for an average of 3 days prior to surgery and up to 2 weeks following surgery. In total, 56 patients with breast cancer were recruited, of whom 35 underwent SLNB and 21 ALND.ResultsPatients who underwent ALND experienced significantly worse PA compared with those who underwent SLNB in week 2 (median 66.4% versus 72.7%, p = 0.015). Subgroup analysis revealed significantly lower PA in simple mastectomy (Mx)-ALND versus Mx-SLNB (median 90.3% versus 70.5%, p = 0.015) in week 2. The PA for SLNB did not return to baseline at 2 weeks after surgery.ConclusionsCompared with SLNB, ALND results in a lower PA level in week 2. The findings also indicate that SLNB has a protracted effect on PA levels, which extend to 2 weeks postoperatively. Monitoring recovery objectively following breast cancer surgery provides patients and surgeons with more information regarding the predicted outcomes of their surgery, which can drive the development of a personalized rehabilitation program.

Rationale, Design, and Methods for the Sedentary Behavior Reduction in Pregnancy Intervention (SPRING): Protocol for a Pilot and Feasibility Randomized Controlled Trial.

Adverse pregnancy outcomes (APOs) identify cardiovascular disease risk, but few effective interventions are available. High sedentary behavior (SED) has recently been associated with APOs, but very few randomized controlled trials (RCTs) have tested SED reduction in pregnancy. The Sedentary Behavior Reduction in Pregnancy Intervention (SPRING) pilot and feasibility RCT addresses this gap by testing the feasibility, acceptability, and preliminary pregnancy health effects of an intervention to reduce SED in pregnant women. The objective of this manuscript is to describe the rationale and design of SPRING. Pregnant participants (n=53) in their first trimester, who are at risk for high SED and APO and without contraindications, are randomized in a 2:1 ratio to an intervention or control group. SED (primary outcome) and standing durations, and steps per day, are measured objectively in each trimester for 1 week with a thigh-mounted activPAL3 accelerometer. SPRING also seeks to demonstrate feasibility and acceptability while estimating preliminary effects on maternal-fetal health outcomes assessed during study visits and abstracted from medical records. The pregnancy-customized intervention promotes daily behavioral targets of less than 9 hours of SED and at least 7500 steps, achieved via increased standing and incorporating light-intensity movement breaks each hour. The multicomponent intervention provides a height-adjustable workstation, a wearable activity monitor, behavioral counseling every 2 weeks (through videoconference), and membership in a private social media group. Herein, we review the rationale, describe recruitment and screening processes, and detail the intervention, assessment protocols, and planned statistical analyses. This study was funded by the American Heart Association (20TPA3549099), with a funding period of January 1, 2021, and until December 31, 2023. Institutional review board approval was obtained on February 24, 2021. Participants were randomized between October 2021 and September 2022, with final data collection planned for May 2023. Analyses and submission of results are expected for winter of 2023. The SPRING RCT will provide initial evidence on the feasibility and acceptability of an SED-reduction intervention to decrease SED in pregnant women. These data will inform the design of a large clinical trial testing SED reduction as a strategy to reduce APO risk. ClincialTrials.gov NCT05093842; https://clinicaltrials.gov/ct2/show/NCT05093842. DERR1-10.2196/48228.

High‐performance piezoelectric yarns for artificial intelligence‐enabled wearable sensing and classification

AbstractPiezoelectric polymer fibers offer a fundamental element in intelligent fabrics with their shape adaptability and energy‐conversion capability for wearable activity and health monitoring applications. Nonetheless, realizing high‐performance smart polymer fibers faces a technical challenge due to the relatively low piezoelectric performance. Here, we demonstrate high‐performance piezoelectric yarns simultaneously equipped with structural robustness and mechanical flexibility. The key to substantially enhanced piezoelectric performance is promoting the electroactive β‐phase formation during electrospinning via adding an adequate amount of barium titanate (BaTiO3) nanoparticles into the poly(vinylidene fluoride‐trifluoroethylene) (P(VDF‐TrFE)). When transformed into a yarn structure by twisting the electrospun mats, the BaTiO3‐doped P(VDF‐TrFE) fibers become mechanically strengthened with significantly improved elastic modulus and ductility. Owing to the tailored convolution neural network algorithms architected for classification, the as‐developed BaTiO3‐doped piezo‐yarn device woven into a cotton fabric exhibits monitoring and identifying capabilities for body signals during seven human motion activities with a high accuracy of 99.6%.image

The Validity of a Novel Low-Cost, Wearable Physical Activity Monitor in a Laboratory Setting

Introduction: Wearable physical activity monitors are popular and may provide a more accurate data than subjective methods. The present study assessed the validity of a novel, low-cost wearable physical activity monitor (Movband 3) relative to established measures. Methods: Participants (N = 19) completed four treadmill stages (1.5, 3.0, 4.0, 6.0 MPH) while wearing the Movband 3 and the validated Actigraph GT1M monitor. Oxygen consumption (VO2 ml/kg/min) and heart rate (beats/min) were recorded. The relationship between Movband data and established measures was assessed via Pearson’s correlations. Tests of agreement were performed for actual and Movband miles traveled. Results: There were large, positive, significant (p &lt; 0.001) effect sizes for the associations between Movband counts and Actigraph counts (r = 0.72), VO2 (r = 0.59), and heart rate (r = 0.63). There was also a large, positive, significant (p &lt; 0.001) association between actual and Movband miles (r = 0.97). However, the difference (Δ) between Movband and actual miles was greater than a null hypothesis of zero (∆ = 0.77 ± 0.45 miles or 31.8%, t = 7.4, p &lt; 0.001). Conclusion: While there was evidence to support the validity of the Movband 3 for the assessment of physical activity intensity this device did not provide an accurate measure of miles traveled.