ActiGraph wGT3X-BT Accelerometer Research Articles

Adding planning strategies to an experiential and conceptual knowledge-based intervention: Does it help to reduce sedentary time?

ObjectiveThe study compared the effects of an “active” control condition addressing conceptual and experiential knowledge about sedentary behavior, with an intervention condition combining conceptual and experiential knowledge together with action planning, coping planning, and behavioral substitution. We targeted a decrease in sedentary time as the primary outcome. MethodsA preregistered trial (#NCT04131270) was carried out with 603 participants aged 11–86 years (M = 33.57; 65.2% women), randomly assigned to the “planning + knowledge” condition or the “knowledge” condition. Sedentary time was assessed with ActiGraph wGT3X-BT accelerometers at baseline, 1-week, and 36-week follow-ups. Conceptual knowledge strategies involved information about health consequences and instructions on how to perform behaviors while experiential knowledge was enhanced by participants taking/discussing photographs of their home environment that has been triggering sedentary behavior. Action/coping plans referred to ways to substitute sedentary behavior with bouts of physical activity behaviors. Mixed models were fit. ResultsNo significant Time × Condition interaction was found. In the total sample, sedentary time estimated to be around 502.34 min/day at baseline, showed a significant linear decline over time (p = .002), by approximately −1.22 min per each month elapsing since baseline (−9.76 min/day across 8 months). ConclusionsThe findings suggest that applying behavior change techniques targeting both conceptual and experiential knowledge about antecedents, circumstances, and consequences of sedentary behavior may result in a small reduction of sedentary time. Adding action plans, coping planning, and behavioral substitution did not improve the effectiveness of the intervention.

Differences in physical activity, sedentary time, and anthropometric variables among children and adolescents: The TUBON project.

Although physical inactivity may lead to increasing obesity prevalence, research on anthropometric variables changes based on physical activity (PA) in children and adolescents is limited. PA decreases with age, while sedentary behavior increases. The study aimed to examine differences in objectively measured sedentary time, light-intensity physical activity (LPA), and moderate-to-vigorous intensity physical activity (MVPA) between children and adolescents, and the differences in the percentiles of anthropometric variables between physically active and inactive groups according to World Health Organization PA recommendations. A total of 759 participants aged 6-17 years (boys, n=358; girls, n=401) were included in the study. The ActiGraph wGT3x-BT accelerometer was used to measure sedentary time, LPA, and MVPA. Height, weight, waist circumference (WC), triceps skinfold thickness (T-SFT), and medial-calf skinfold thickness (M-SFT) were measured. Body fat percentage (BF%) and body mass index (BMI) were calculated, and the percentiles of anthropometric variables were categorized. The findings showed that children had less sedentary time and a higher LPA than adolescents for both genders (p<0.05). Children had a higher MVPA than adolescents in girls (p<0.05), but the difference was insignificant in boys (p>0.05). In boys, physically active children were in lower percentiles for T-SFT and BF% than those who did not (p<0.05). In boys, adolescents who were physically inactive were in higher percentiles for BMI, T-SFT, M-SFT, and BF% (p<0.05). In addition, in girls, adolescents who were physically active were in lower percentiles of BMI, M-SFT, and BF%, whereas children who were physically active were in lower percentiles of M-SFT and BF% (p<0.05). Sedentary time increases while PA decreases with age. Children and adolescents who met the WHO PA recommendation had lower percentiles of anthropometric variables, indicating the importance of PA in preventing obesity in these age groups.

Associations Between Childcare Physical Activity and Sedentary Time and Early Childhood Developmental Outcomes: A Compositional and Isotemporal Substitution Analysis.

Physical activity and sedentary time are independently associated with health and developmental outcomes in preschool children. However, the integrated nature of these behaviours on early life outcomes, particularly during childcare hours, is currently understudied. As such, the aim of this study was to examine the association between preschool children's physical activity and sedentary time during childcare and various developmental outcomes (psychosocial, cognitive and fundamental movement skills). A total of 107 preschool children (Mage: 41 ± 6 months) recruited from London, Canada, wore ActiGraph wGT3X-BT accelerometers during childcare hours to measure their sedentary time, light intensity physical activity (LPA) and moderate-to-vigorous intensity physical activity (MVPA). Developmental outcomes, including psychosocial health (internalising, externalising, prosocial behaviour), indicators of cognitive development (memory, inhibitory control) and fundamental movement skills (locomotor control, object control, total fundamental movement), were assessed using validated tools. Compositional regression and isotemporal substitution models were estimated to examine how movement compositions in childcare were associated with developmental outcomes. Engaging in more MVPA relative to LPA and sedentary time was associated with fewer internalising symptoms and better total fundamental movement skills and object control skills, whilst spending more time in LPA relative to MVPA and sedentary time was associated with more internalising symptoms and worse object control skills. Isotemporal substitution models suggested that theoretically increasing sedentary time or engaging in MVPA at the expense of time engaging in LPA during childcare is associated with lower internalising symptoms. The findings of this study provide preliminary evidence that engaging in MVPA during childcare, at the expense of time in LPA or sedentary time, is associated with children's fundamental movement skills and psychosocial development. Further longitudinal research is required, with larger samples of young children, to assess the mechanisms through which childcare movement behaviour compositions may interact with developmental outcomes, including contextualising both sedentary time and LPA. ClinicalTrials.gov identifier: NCT05359536.

The Cross-Sectional and Longitudinal Associations Between Adherence to 24-Hour Movement Behavior Guidelines and Bone Health in Young Children.

Adherence to the World Health Organization's 24-hour movement behavior (24-HMB) guidelines is associated with various health outcomes. However, its relationship with bone mineral density (BMD) in young children has not been investigated. This study aimed to examine the cross-sectional and longitudinal associations between adherence to the 24-HMB guidelines and BMD in young children. A total of 120 children aged 3-5 years were recruited from three kindergartens in Changsha, Hunan, China. Physical activity (PA) was objectively measured using ActiGraph wGT3X-BT accelerometers, and BMD was assessed using the Sunlight Omnisense 7000P ultrasound device. Screen time (ST) and sleep duration (SD) were reported by parents. Logistic regression was used to analyze the associations between guideline adherence and BMD. Only 5.5% of the participants met all three guidelines for PA, ST, and SD, while 16.5% did not meet any. In the cross-sectional analysis, young children who met both ST and SD guidelines (OR = 0.29, 95% CI: 0.09, 0.95) had a lower risk of insufficient BMD compared to those who met none. In the one-year cohort follow-up, young children who met the PA guideline at baseline (OR = 0.22, 95% CI: 0.07, 0.71), as well as those who met both the PA and ST guidelines (OR = 0.18, 95% CI: 0.04, 0.83) or all three (OR = 0.13, 95% CI: 0.03, 0.69), had a lower risk of insufficient BMD at one year. Adherence to the 24-HMB guidelines may promote bone health in young children. Future research should prioritize achievable goals, such as limiting ST and ensuring adequate SD, while gradually increasing MVPA to optimize bone development.

Influence of physical activity and screen time on sleep quality in primary school students

In a society where, sedentary lifestyles and the use of technological screens are on the rise, students' lifestyle is being significantly affected. In fact, nowadays many students experience various sleep problems, and two of its main factors may be physical activity and the use of technological screens. In this sense, this research aimed to analyze the influence of students' physical activity and the screen time on sleep quality of students. The participants were 28 students in 5th and 6th grade of primary school. They wore ActiGraph WGT3X-BT accelerometers for one week to collect data related to physical activity and sleep patterns. Additionally, a survey was conducted to assess their use of technological screens. The collected data were analyzed, with a focus on differences by sex. Correlations between these parameters were also analyzed. The analysis revealed no significant correlation between physical activity and sleep quality. However, a significant correlation was observed between screen time and sleep quality. This finding highlights the importance of continued research in these areas to enhance the wellbeing and sleep quality of students.

The moderating influence of social cognition in the relationship between affect and physical activity in adolescents: An ecological momentary assessment study

BackgroundAffective states influence subsequent engagement in physical activity, but the nature of this relationship varies substantially from person-to-person (e.g., negative affect may precede increased physical activity for some adolescents and decreased for others). PurposeExplore which variables may explain the individual differences in the relationship between incidental affect and moderate to vigorous physical activity (MVPA). MethodsThis study explores social cognitive variables as moderators of the relationship between incidental affect and MVPA through a 20-day ecological momentary assessment (EMA) study, in which 100 adolescents aged 13–18 years old (M = 14.45, SD = 1.37) were asked to complete a baseline assessment of their self-efficacy and outcome expectancies. Subsequently, wore an Actigraph (wGT3X-BT) accelerometer 24 h per day on their non-dominant wrist and answered EMA surveys assessing affect 4 times per day using time-based signaling. ResultsWithin-person negative affect predicted MVPA (b = −0.15 p < .05) with 95% CI [-0.29, −0.01], as did between-person negative affect (b = 0.08 p < .05) with 95% CI [0.01, 0.15]. Additionally, there was a significant interaction between within-person negative affect and self-efficacy such that for individuals low in self-efficacy (<2.08 on a 5-point scale) increased negative affect led to decreased MVPA (b = −0.06, p < .05), but not for individuals high in self-efficacy (>5.14 on a 5-point scale; b = 0.07, p < .05). ConclusionsResults indicate that self-efficacy is an important target for overcoming the deleterious effects of momentary negative affect on MVPA and suggests just-in-time intervention techniques for individuals who are typical or low in self-efficacy.

Individual, dyadic, collaborative planning, physical activity, and nutrition: A randomized controlled trial in parent-child dyads.

This study was designed to investigate the effects of individual, dyadic, and collaborative planning on moderate-to-vigorous physical activity (MVPA; primary outcome) and energy-dense food intake (secondary outcome) in dyads of parents and their 9-15-year-old children. Individual planning reflects an "I-for-me" planning of one person's behavior. Collaborative ("we-for-us") planning refers to joint planning of both dyad members' behavior, whereas dyadic ("we-for-me") planning involves joint planning of only the target person's behavior. N = 247 dyads participated in a randomized controlled trial with individual, dyadic, or collaborative physical activity (PA) planning and control conditions (education about PA, sedentary behavior, nutrition, energy intake-expenditure balance). MVPA was measured with ActiGraph wGT3X-BT accelerometers at baseline, 1-week, and 36-week follow-ups. Energy-dense food intake was self-reported at baseline, 9-week, and 36-week follow-ups. Linear mixed models were fit for parents and children separately. At the 36-week follow-up, children in the dyadic "we-for-me" planning condition decreased their MVPA compared to the control condition. At the same time, children in the dyadic planning condition also decreased energy-dense food intake at the 36-week follow-up. No effects were found among children in individual and collaborative PA planning conditions. Parents in any experimental conditions decreased energy-dense food intake. Children's decrease in MVPA in dyadic PA planning condition was offset by a reduction of energy intake, which may represent a compensatory mechanism. The limited effectiveness of the dyadic "we-for-me" interventions in parent-child dyads may result from young people's needs for individuation and their reactance to parental support. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Multicentre investigation on the effect of decompressive surgery on Balance and physical ActiviTy Levels amongst patients with lumbar Spinal stenosis (B-ATLAS): protocol for a prospective cohort study

IntroductionPatients with lumbar spinal stenosis may have poor balance, decreased physical function and problems maintaining physical activity levels due to radiculopathy. Decompressive surgery is often indicated if conservative management fails...

Predicting physical activity behavior among university students using the multi-process action control framework

Most university students do not engage in enough physical activity (PA) despite the known physical and mental health benefits. Action control theories such as the Multi-Process Action Control (M-PAC) framework have been proposed to better understand the translation of intentions into action by incorporating post-intentional processes. However, the explanatory power of the M-PAC framework beyond traditional social cognitive constructs has received limited attention. This study examined the predictive utility of the M-PAC framework for explaining variance in self-reported and device-measured PA behavior among university students. A total of 2418 undergraduate students (Mean age = 19.1 ± 1.73 [SD] years) completed an online survey that included a self-reported measure of moderate-to-vigorous PA (MVPA) as well as constructs outlined in the M-PAC framework: instrumental and affective attitudes, perceived capability and opportunity, behavioral regulation, habit and identity. A subsample (n = 376) also wore an ActiGraph wGT3x-BT accelerometer on their non-dominant wrist for seven full days to assess MVPA. Robust linear regression models were computed to investigate associations between M-PAC framework constructs and PA behavior. Findings showed the M-PAC framework explained as high as 14.3 % and 37.9 % of the variance in device-measured and self-reported MVPA, respectively. Regulatory (behavioral regulation), and reflexive (habit and identity) processes were significant predictors of self-reported MVPA when examining the full M-PAC framework, whereas the role identity dimension of PA identity was the only significant predictor of device-assessed MVPA. Taken together, these results reinforce the importance of post-intentional processes, specifically role identity, in understanding PA behavior among university students.

Reliability and Validity of the Global Physical Activity Questionnaire for Portuguese Adults.

The Global Physical Activity Questionnaire (GPAQ) has been used often to assess physical activity (PA) patterns. However, the European Portuguese version of this instrument has not been validated. We aimed to validate the self-administered GPAQ, version 2, (GPAQv2) for Portuguese adults. We included 32 participants in a pilot study of a Portuguese adaptation of the test and 108 participants in an assessment of their PA patterns and sedentary behavior (SB) through the GPAQv2. For its validation, we compared the GPAQv2 to the International PA Questionnaire-Long Form (IPAQ-LF) (concurrent validity) and the ActiGraph wGT3X-BT accelerometer (criterion validity). We evaluated PA and SB at baseline and after seven consecutive days. Test-retest reliability with the Kappa test (k) and the Intraclass Correlation Coefficient (ICC) ranged from strong to almost perfect (k: 0.864-0.976) and from moderate to excellent (ICC: 0.56-0.994), respectively. Concurrent validity, assessed by Spearman's Correlation Coefficient, was moderate to substantial (rho: 0.471-0.680), and there was fair to substantial criterion validity (rho: 0.226-0.672). Bland-Altman plots showed that the GPAQv2 overestimated vigorous and moderate to vigorous PA and underestimated moderate PA. The largest difference values were related to SB, since the GPAQv2 underestimated sitting time. In sum, we found the GPAQv2 to have acceptable validity and reliability for assessing PA and SB patterns, and we recommend its use for Portuguese adults.

Development and validation of the Global Adolescent and Child Physical Activity Questionnaire (GAC-PAQ) in 14 countries: study protocol

IntroductionGlobal surveillance of physical activity (PA) of children and adolescents with questionnaires is limited by the use of instruments developed in high-income countries (HICs) lacking sociocultural adaptation, especially in low-...

Accelerometer-Measured Physical Activity, Fitness and Indicators of Cardiometabolic Risk among Rural Adolescents: A Cross-Sectional Study at 15-Year Follow-up of the MINIMat Cohort.

Little is known about the relationship of physical activity (PA) and fitness with cardiometabolic risk among rural adolescents in low- and middle-income countries. Thus, we examined the associations of PA and fitness with selected cardiometabolic indicators along with potential gender-based differences in a birth cohort of rural adolescents from southeast Bangladesh. We utilized data from the 15-year follow-up of Maternal and Infant Nutrition Interventions in Matlab (MINIMat) cohort (n = 2253). Wrist-worn ActiGraph wGT3x-BT accelerometers were used to estimate sedentary time (ST) and PA. Fitness was assessed using: handgrip strength, standing long jump, and Chester Step Test. Anthropometric parameters, systolic blood pressure (SBP), and fasting lipid, insulin and glucose levels were measured. We calculated insulin resistance using the Homeostasis Model Assessment equation (HOMA-IR). Linear regression and isotemporal substitution models were fitted. The adolescents spent 64min/day (inter-quartile range: 50-81) in moderate-to-vigorous physical activity (MVPA). A 10-minute-per-day higher vigorous PA (VPA) was associated with: 4.9% (95% confidence interval (CI): 2.9-6.8%) lower waist circumference (WC), 3.2 mmHg (95% CI: 1.5-4.8) lower SBP, 10.4% (95% CI: 2.9-17.3%) lower TG, and 24.4% (95% CI: 11.3-34.9%) lower HOMA-IR. MVPA showed similar associations of notably smaller magnitude. Except for WC, the associations were more pronounced among the boys. Substituting ST with VPA of equal duration was associated with lower WC, SBP, triglyceride and HOMA-IR. Grip strength was favorably associated with all indicators, displaying considerably large effect sizes. Our findings indicated beneficial roles of PA- particularly VPA- and muscular fitness in shaping cardiometabolic profile in mid-adolescence. VPA and grip strength may represent potential targets for preventive strategies tailored to adolescents in resource-limited settings.

Correlation between Physical Activity Time Reported by the IPAQ and Accelerometer in Syrian Adults

Background: The accelerometer and self-report questionnaires have been recommended as efficient methods to measure physical activity (PA). The aim of this work is to investigate issues associated with PA assessment using the ActiGraph WGT3X-BT (AG) accelerometer and the Syrian version of the International Physical Activity Questionnaire-short form (IPAQ-SF-SY) in adults living in Damascus city.Methods: A sample of 52 (age 18- 60 years) Syrian men (17) and women (35) in a cross-sectional study wore the AG accelerometer for seven days and completed the IPAQ-SF-SY on the seventh day. Total PA, time spends in standing and sitting assessed by IPAQ-SF-SY and AG accelerometer were compared.Results: The IPAQ-SF-SY overestimates PA time among Syrian adults. IPAQ-SF-SY reported more time of total PA [763(660) vs 607(149) min, p=0.003], vigorous PA [29(1) vs 1(0.2) min, p=0.524], moderate PA [94(76) vs 42(22) min, p=0.032], MVPA [122(106) vs 43(22) min, p=0.019], and significantly less sedentary time than AG accelerometer [447(180) vs 643(93) min, p=0.728], mean (SD) respectively. Some differences were noticed in the correlations by gender, age, BMI, education statues, and smoking for PA and sedentary behavior (SB). For all correlations, there were no significant differences between sub groups.Conclusions: Data suggest that it is important to improve the specificity and sensitivity of the IPAQ-SF-SY with Arabic-speaking subjects and further study is needed to approve the utilization of PA self-report in Arabic.

Individual and school correlates of body mass index and cardiorespiratory fitness in primary school children from the REACT project: A multivariate multilevel analysis.

This paper examines the relationship between body mass index (BMI) and cardiorespiratory fitness (CRF) using a multivariate multilevel approach and investigates the links between individual and school-related correlates with children's BMI and CRF. This cross-sectional sample included 1014 children (6-10 years) from 25 Portuguese primary schools. BMI was calculated, and CRF was assessed with the PACER test. Fundamental movement skills (FMS) included five object control tasks. Moderate-to-vigorous physical activity (MVPA), sleep, and sedentary time were assessed with the ActiGraph wGT3X-BT accelerometer. Socioeconomic status (SES) and school variables were also obtained. A multivariate multilevel model was used, and alpha was set at 5%. BMI and CRF systematically increased with age. Most of the joint variance (94.4%) was explained at the child level, and BMI and CRF were correlated at this level (ρ = -.37). More active children demonstrated higher CRF levels and had lower BMI levels; sedentary and sleep time were not significantly associated with BMI or CRF. FMS were positively associated with CRF but were not significantly associated with BMI. Children at higher SES were more fit and had lower BMI than their peers of lower SES. Finally, school-level variables were not significantly related to BMI and CRF. BMI and CRF had a low but statistically significant negative correlation in this sample of children. Most of the variation in BMI and CRF was explained by child-level characteristics.

Association between physical activity, sedentary behavior patterns with bone health among Chinese older women

IntroductionWe examined the association between physical activity (PA) and sedentary behavior (SEB) time with bone health and whether it changes depending on different patterns. Materials and methodsCross-sectional data were derived from the baseline of the Physical Activity and Health in Older Women Study. PA and SEB were measured using Actigraph wGT3X-BT accelerometers. Bone mineral density (BMD) was derived from the SONOST-2000 ultrasound bone densitometer, with unhealthy bone defined as a BMD T-score of <2.5 standard deviation a young adult reference population's mean. A 10 min-bouted SEB was defined as an SEB duration of >10 min (allow 2 min 0 counts), similar to 30 min-bouted and 60 min-bouted SEBs. Sporadic and bouted PAs were defined by PA duration of <10 min or ≥ 10 min. Multivariate logistic regression analysis investigated the associations between PA and SEB patterns with bone health. ResultsAmong 1111 female participants, 42.12 % had unhealthy bones. In a fully-adjusted model, increasing 30 min/day of SEB was associated with a higher odds ratio (OR) for an unhealthy bone (OR, 1.08; P = 0.005), similar to the 10 (OR, 1.06; P = 0.012), 30 (OR, 1.06; P = 0.043), and 60 min-bouted (OR 1.08, P = 0.032) SEBs. Total light PA (LPA) time (OR, 0.97; P = 0.005) had a lower OR for unhealthy bone. After adjusting for sporadic LPA time, bouted LPA (OR, 0.97; P = 0.005) retained this association. No association was observed between total moderate-to-vigorous PA (MVPA) and bone health, sporadic MVPA, and bouted MVPA. ConclusionsPerforming bouted LPA and reducing 10 min-bouted SEB may maintain bone health.

Comparison of Sleep and Physical Activity Metrics From Wrist-Worn ActiGraph wGT3X-BT and GT9X Accelerometers During Free-Living in Adults

Background: ActiGraph accelerometers can monitor sleep and physical activity (PA) during free-living, but there is a need to confirm agreement in outcomes between different models. Methods: Sleep and PA metrics from two ActiGraphs were compared after participants (N = 30) wore a GT9X and wGT3X-BT on their nondominant wrist for 7 days during free-living. PA metrics including total steps, counts, average acceleration—Euclidean Norm Minus One (ENMO) and Mean Amplitude Deviation, intensity gradient, the minimum acceleration value of the most active 10 and 30 min (M10, M30), time spent in activity intensities from vector magnitude (VM) counts, and ENMO cut points and sleep metrics (sleep period time window, sleep duration, sleep onset, and waking time) were compared. Results: Excellent agreement was evident for average acceleration-Mean Amplitude Deviation, counts, total steps, M10, and light PA (VM counts) with good agreement evident from the remaining PA metrics apart from moderate–vigorous PA (VM counts) which demonstrated moderate agreement. Mean bias for all PA metrics were low, as were the limits of agreement for the intensity gradient, average acceleration-Mean Amplitude Deviation, and inactive time (ENMO and VM counts). The limits of agreement for all other PA metrics were &gt;10%. Excellent agreement, low mean bias, and narrow limits of agreement were evident for all sleep metrics. All sleep and PA metrics demonstrated equivalence (equivalence zone of ≤10%) apart from moderate–vigorous PA (ENMO) which needed an equivalence zone of 16%. Conclusions: Equivalent estimates of almost all PA and sleep metrics are provided from the GT9X and wGT3X-BT worn on the nondominant wrist.

Extent and Impact of Accelerometer Time Drift on Linkage With Global Positioning System Data for Physical Activity Research

Background: Accelerometer time may drift, whereas global positioning system time does not (due to constant satellite communication), potentially impacting linkage of these data; the impact of this issue on outcome measures is unknown. Our study assessed if time drift is consistent between devices and/or data collection waves and the impacts on common outcomes in built environment physical activity research. Methods: First, 11 ActiGraph wGT3X-BT accelerometers were manually or automatically shaken every 6 hr for 10 days, and this experiment was repeated twice (two waves). Accelerometer time was compared with local atomic clock time to identify time drifts. Next, we assessed the time-drift impact on estimates of park moderate to vigorous physical activity in an outdoor experiment, comparing no adjustment (status quo) to device-specific and average adjustment to account for time drift. Finally, we used data from an ongoing health study in Detroit, Michigan, to evaluate the impact of time drift adjustment on free-living linked accelerometer and global positioning system data. Results: There was an average of 6.1 ± 5.1 s of lag in accelerometer time after 10 days, but time drifts varied among accelerometers. Mean absolute differences in park moderate to vigorous physical activity were 0.4–0.5 min/day over the entire outdoor experiment or 0.8–0.9 min/day on Day 7. In the free-living study, overall differences in park moderate to vigorous physical activity were 0.0–0.1 min/day, but the maximum difference was 1.9 min/day. Conclusions: Time drift had little impact on estimates, although research requiring high temporal resolution should assess the time drift of individual accelerometers before data collection to account for drift, particularly when linking to global positioning system data.

Validation of Proprietary and Novel Step-counting Algorithms for Individuals Ambulating With a Lower Limb Prosthesis

ObjectiveTo compare the accuracy and reliability of 10 different accelerometer-based step-counting algorithms for individuals with lower limb loss, accounting for different clinical characteristics and real-world activities. DesignCross-sectional study. SettingGeneral community setting (ie, institutional research laboratory and community free-living). ParticipantsForty-eight individuals with a lower limb amputation (N=48) wore an ActiGraph (AG) wGT3x-BT accelerometer proximal to the foot of their prosthetic limb during labeled indoor/outdoor activities and community free-living. InterventionsNot applicable. Main Outcome MeasuresIntraclass correlation coefficient (ICC), absolute and root mean square error (RMSE), and Bland Altman plots were used to compare true (manual) step counts to estimated step counts from the proprietary AG Default algorithm and low frequency extension filter, as well as from 8 novel algorithms based on continuous wavelet transforms, fast Fourier transforms (FFTs), and peak detection. ResultsAll algorithms had excellent agreement with manual step counts (ICC>0.9). The AG Default and FFT algorithms had the highest overall error (RMSE=17.81 and 19.91 steps, respectively), widest limits of agreement, and highest error during outdoor and ramp ambulation. The AG Default algorithm also had among the highest error during indoor ambulation and stairs, while a FFT algorithm had the highest error during stationary tasks. Peak detection algorithms, especially those using pre-set parameters with a trial-specific component, had among the lowest error across all activities (RMSE=4.07-8.99 steps). ConclusionsBecause of its simplicity and accuracy across activities and clinical characteristics, we recommend the peak detection algorithm with set parameters to count steps using a prosthetic-worn AG among individuals with lower limb loss for clinical and research applications.

Motor competence, motivation and enjoyment in physical education to profile children in relation to physical activity behaviors

ABSTRACT Background: Motor competence (MC) has been recognized as a main goal in Physical Education (PE) and a determining element for the promotion of Physical Activity (PA). The interaction between MC and PA would be mediated not only by physical factors, but also by psychological and affective factors, so their study should consider an integral perspective. Evidence suggests that actual and perceived motor competence, motivation and enjoyment of PE classes play an important role in schoolchildren's PA practice. However, not all the schoolchildren behave in a similar manner, so it is necessary to understand how the combination of these variables can establish different subpopulations with different individual realities. Purpose: Following a person-centered approach, the present study aims (1) to examine profiles of Chilean children according to Actual Motor Competence (AMC), Perceived Motor Competence (PMC), intrinsic motivation and enjoyment of PE classes, and (2) to analyze how these profiles behave in relation to BMI and Physical Activity. Methods: Seven hundred and thirty schoolchildren (46.3% girls, age M = 11.22 SD = 0.70) in 5th and 6th grade of primary school participated. The instruments used for assessment were: MOBAK 5–6 test (AMC); SEMOK questionnaire (PMC); Questionnaire of Motivation in PE in Primary Education (intrinsic motivation); Physical Activity Enjoyment Scale (enjoyment); and ActiGraph wGT3X-BT accelerometers (PA). Latent class analysis was conducted to identify homogeneous groups of schoolchildren with respect to AMC, PMC, intrinsic motivation and enjoyment of PE classes. Findings: Three-class solution was the best fit for the data. Profile 1 (high aligned) represents 21.9% of the sample, with high levels of AMC, PMC, motivation and enjoyment of PE classes. Profile 2 (nonaligned) represents 67.5% of the sample, with low levels of AMC, medium levels of PMC, and high motivation and enjoyment. Profile 3 (low aligned) represents 10.5% of the sample, with low levels of AMC and PMC, motivation and enjoyment. Schoolchildren of profile 1 were more active, with more daily minutes of MVPA, compared to schoolchildren of profile 2 or 3. The schoolchildren of profile 1 have a lower BMI than the schoolchildren of profile 2 or profile 3. Conclusion: Children of two of the profiles, involving the majority of the sample, may be at risk of unhealthy lifestyles, with less motivation and enjoyment for PE classes. Therefore, for PE classes and PA programs, it is important to give the same importance to psychological and affective factors as to purely physical ones. The teaching methodologies should put an emphasis on the development of AMC and PMC, through didactic strategies that encourage autonomous motivation and provide pleasant experiences for the schoolchildren.

Short-Form Video Exposure and Its Two-Sided Effect on the Physical Activity of Older Community Women in China: Secondary Data Analysis.

There is a tendency for older adults to become more physically inactive, especially older women. Physical inactivity has been exacerbated since the COVID-19 pandemic. Lockdowns and information-based preventive measures for COVID-19 increased the number of short-form video app users and short-form video exposure, including content exposure and the duration of exposure, which has demonstrated important effects on youths' health and health-related behaviors. Despite more older adults viewing short-form videos, less is known about the status of their short-form video exposure or the impacts of the exposure on their physical activity. This study aims to describe physical activity-related content exposure among older adults and to quantify its impacts along with the duration of short-form video exposure on step counts, low-intensity physical activity (LPA), and moderate-to-vigorous physical activity (MVPA). We analyzed a subsample (N=476) of older women who used smartphones and installed short-form video apps, using the baseline data collected from an ongoing cohort study named the Physical Activity and Health in Older Women Study (PAHIOWS) launched from March to June 2021 in Yantai, Shandong Province, China. The information on short-form video exposure was collected by unstructured questions; physical activity-related content exposure was finalized by professionals using the Q-methodology, and the duration of exposure was transformed into hours per day. Step counts, LPA, and MVPA were assessed with ActiGraph wGT3X-BT accelerometers. Multiple subjective and objective covariates were assessed. Linear regression models were used to test the effects of short-form video exposure on step counts, LPA, and MVPA. MVPA was dichotomized into less than 150 minutes per week and 150 minutes or more per week, and the binary logistic regression model was run to test the effects of short-form video exposure on the achievement of spending 150 minutes or more on MVPA. Of 476 older women (mean age 64.63, SD 2.90 years), 23.7% (113/476) were exposed to physical activity-related short-form videos, and their daily exposure to short-form videos was 1.5 hours. Physical activity-related content exposure increased the minutes spent on MVPA by older women (B=4.14, 95% CI 0.13-8.15); the longer duration of short-form video exposure was associated with a reduced step count (B=-322.58, 95% CI -500.24 to -144.92) and minutes engaged in LPA (B=-6.95, 95% CI -12.19 to -1.71) and MVPA (B=-1.56, 95% CI -2.82 to -0.29). Neither content exposure nor the duration of exposure significantly increased or decreased the odds of older women engaging in MVPA for 150 minutes or more per week. Short-form video exposure has both positive and negative impacts on the physical activity of older adults. Efforts are needed to develop strategies to leverage the benefits while avoiding the harms of short-form videos.