Introduction: Accelerometer-based measurements of physical activity types are commonly used to replace self-reports. To advance the field, it is desirable that such measurements allow accurate detection of key daily physical activity types. This study aimed to evaluate the performance of a machine learning classifier for detecting sitting, standing, lying, walking, running, and cycling based on a dual versus single accelerometer setups during free-living. Methods: Twenty-two adults (mean age [SD, range] 38.7 [14.4, 25–68] years) were wearing two Axivity AX3 accelerometers positioned on the low back and thigh along with a GoPro camera positioned on the chest to record lower body movements during free-living. The labeled videos were used as ground truth for training an eXtreme Gradient Boosting classifier using window lengths of 1, 3, and 5 s. Performance of the classifier was evaluated using leave-one-out cross-validation. Results: Total recording time was ∼38 hr. Based on 5-s windowing, the overall accuracy was 96% for the dual accelerometer setup and 93% and 84% for the single thigh and back accelerometer setups, respectively. The decreased accuracy for the single accelerometer setup was due to a poor precision in detecting lying based on the thigh accelerometer recording (77%) and standing based on the back accelerometer recording (64%). Conclusion: Key daily physical activity types can be accurately detected during free-living based on dual accelerometer recording, using an eXtreme Gradient Boosting classifier. The overall accuracy decreases marginally when predictions are based on single thigh accelerometer recording, but detection of lying is poor.
Kerstin Bach, Atle Kongsvold, Hilde Bårdstu, Ellen Marie Bardal, Håkon S. Kjærnli, Sverre Herland, Aleksej Logacjov, and Paul Jarle Mork
Logan T. Markwell, Andrew J. Strick, and Jared M. Porter
Sports, along with nearly all facets of life, have been impacted by the COVID-19 pandemic. The National Basketball Association quickly adopted a unique method to finish the 2019–2020 regular season and playoffs. The entire league quarantined for months in what was known as the “NBA bubble” where games were played in spectator-less arenas. During this time, increases in shooting accuracy were reported, suggesting that free throws and field goals were made at record-breaking levels. This study examined differences in free throw shooting accuracy with and without spectators. Archival data were retrieved and analyzed to evaluate the potential differences. Free throw shooting accuracy with and without spectators were examined in multiple analyses. Our examination revealed free throw percentages were significantly greater in spectator-less arenas compared with the 2018 and 2019 seasons with spectators. Changes of the environmental characteristics, due to spectator-less arenas, were likely contributors to the improved free throw phenomenon reported in this study.
Alexandra Stribing, Adam Pennell, Emily N. Gilbert, Lauren J. Lieberman, and Ali Brian
Individuals with visual impairments (VI) trend toward lower motor competence when compared with peers without VI. Various forms of perception often affects motor competence. Thus, it is important to explore factors that influence forms of perception and their differential effects on motor competence for those with VI. Therefore, the purposes of this study were to explore and describe the differential effects of age, gender, and degree of vision on self-perceptions, parents’ perceptions, metaperceptions, and locomotor skills, and to examine potential associations among all variables with actual locomotor competence for adolescents with VI. Adolescents with VI completed two questionnaires and the Test of Gross Motor Development-Third Edition. Parents completed a parent perception questionnaire. Mann–Whitney U and Kruskal–Wallis H analyses showed no differential effects for gender or age on any dependent measures. Degree of vision affected locomotor skills, but not any other factor. Spearman rho correlations showed significant associations among locomotor and self-perceptions, degree of vision and locomotor, and metaperceptions with parents’ perceptions. Adolescents reported relatively high self-perceptions and metaperceptions; however, their actual locomotor competence and parents’ perceptions were relatively low. Findings may help situate future intervention strategies targeting parents supporting their children’s locomotor skills through self-perceptions.
Jennifer L. Gay and David M. Buchner
Introduction: Little is known about the stability of occupational physical activity (PA) and documented compensation effects over time. Study objectives were to (a) determine the stability of accelerometer estimates of occupational and nonoccupational PA over 6 months and 1 year in adults who do not change jobs, (b) examine PA stability in office workers relative to employees with nonoffice jobs who may be more susceptible to seasonal perturbations in work tasks, and (c) examine the stability data for compensation effects seen at baseline in this sample. Methods: City/county government workers from a variety of labor sectors wore an accelerometer at initial data collection, and at 6 (n = 98) and 12 months (n = 38) following initial data collection. Intraclass correlation coefficients (ICCs) were calculated for accelerometer counts and minutes by intensity, domain, and office worker status. Partial correlation coefficients were examined for compensation effects. Results: ICCs ranged from .19 to .91 for occupational and nonwork activity variables. ICCs were similar by office worker status. In both counts and minutes, greater occupational PA correlated with lower total nonwork PA. However, as minutes of occupational moderate to vigorous physical activity increased, nonoccupational moderate to vigorous physical activity did not decrease. Conclusions: There was moderate to high stability in occupational and nonoccupational PA over 6- and 12-month data collection. Occupational PA stability was greater in nonoffice workers, suggesting that those employees’ PA may be less prone to potential cyclical factors at the workplace. Confirmation of the compensation effect further supports the need for workplace intervention studies to examine changes in all intensities of activity during and outside of work time.
Paul Bernard Rukavina
The deleterious effects of weight bias in physical activity spaces for children, adolescents, and adults are well documented. Different types of weight bias occur, and they interact at multiple levels within a person’s ecology, from the messaging of often unattainable sociocultural thin/muscular ideals and physical inequities (e.g., equipment not appropriate for body shapes and sizes) to interpersonal and public discriminatory comments. However, the most damaging is the internalization and application of negative weight-bias stereotypes by those with overweight and obesity to themselves. An imperative for social justice is now; there is great need to advocate for, provide support for, and design inclusive physical activity spaces to reduce weight bias so that all individuals feel welcome, accept their bodies, and are empowered to live a healthy, active lifestyle. To make this a reality, an interdisciplinary and preventive approach is needed to understand bias and how to minimize it in our spaces.
Arto J. Pesola, Timo Rantalainen, Ying Gao, and Taija Finni
Objective: Habitual walking is important for health and can be measured with accelerometry, but accelerometry does not measure physiological effort relative to capacity. We compared accelerometer-measured absolute intensity and electromyography (EMG)-measured relative muscle activity between people with low versus excellent aerobic fitness levels during their habitual walking. Methods: Forty volunteers (19 women; age 49.3 ± 17.1 years, body mass index 24.0 ± 2.6 kg/m2; peak oxygen uptake 40.3 ± 12.5 ml/kg/min) wore EMG-shorts and a hip-worn accelerometer simultaneously for 11.6 ± 2.2 hr on 1.7 ± 1.1 days. Continuous gait bouts of at least 5-min duration were identified based on acceleration mean amplitude deviation (MAD, in milli gravitational acceleration, mg) and mean EMG amplitude, with EMG normalized to maximal isometric knee extension and flexion (EMG, in percentage of maximal voluntary contraction EMG). Peak oxygen uptake was measured on a treadmill and maximal strength in isometric leg press (leg press max). MAD and EMG were compared between age- and sex-specific fitness groups (low-average, good, and excellent) and in linear models. Results: During habitual walking bouts (4.1 ± 4.1 bouts/day, 0.9 ± 1.0 min/bout), the low-average fit participants had an approximately 28% lower MAD (245 ± 64.3 mg) compared with both good fit and excellent fit participants (313 ± 68.1 mg, p < .05), but EMG was the same (13.1% ± 8.42% maximal voluntary contraction EMG, p = .10). Absolute, relative to body mass, and relative to skeletal muscle mass peak oxygen uptake (but not leg press max) was positively associated with MAD independent of age and sex (p < .01), but there were no associations with EMG. Conclusions: People with low-average aerobic capacity habitually walk with a lower accelerometer-measured absolute intensity, but the physiological stimulus for lower-extremity muscles is similar to those with excellent aerobic capacity. This should be considered when measuring and prescribing walking for health.
Lewis King, SarahJane Cullen, Jean McArdle, Adrian McGoldrick, Jennifer Pugh, Giles Warrington, and Ciara Losty
A large proportion of jockeys report symptoms associated with mental health difficulties (MHDs), yet most do not seek help from professional mental health support services. Due to the paucity of literature in this field, this study sought to explore jockeys’ barriers to, and facilitators of, help-seeking for MHDs. Twelve jockeys participated in semistructured interviews, subsequently analyzed via reflexive thematic analysis. Barriers to help-seeking included the negative perceptions of others (stigma and career implications), cultural norms (masculinity and self-reliance), and low mental health literacy (not knowing where to seek help, minimization of MHDs, negative perceptions of treatment, and recognizing symptoms). Facilitators to help-seeking included education (exposure to psychological support at a younger age), social support (from professionals, jockeys, family, and friends), and media campaigns (high-profile disclosures from jockeys). Findings are consistent with barrier and facilitator studies among general and athletic populations. Applied recommendations and future research considerations are presented throughout the manuscript.
Deborah Johnson-Shelton, Jeanette Ricci, Erika Westling, Missy Peterson, and Julie C. Rusby
Background: Elementary school teachers are often responsible for teaching physical education to their students, with little formal training in that instruction. This study evaluates a trainer in residence professional development program designed to improve physical education instructional attitudes and practices in elementary school generalist teachers. Methods: Participants were 139 teachers and 3577 first to fifth grade students at 11 public elementary schools in Oregon. Program evaluation measures included pre- and postteacher surveys on teacher attitudes and practices toward teaching physical education for fidelity, postprogram lesson observations for sustainability, and teacher-reported program barriers to and facilitators of feasibility. A multivariate repeated-measures analysis of covariance test assessed changes in teacher attitudes and practices related to physical education instruction. Results: There were main effects of time observed for teacher encouragement and enthusiasm and physical education teaching practices (F
2,127 = 9.68, P < .001,
Jemima C. John, Natalia I. Heredia, Lorna H. McNeill, Deanna M. Hoelscher, Sue Schembre, MinJae Lee, Jasmine J. Opusunju, Margaret Goetz, Maria Aguirre, Belinda M. Reininger, and Larkin L. Strong
Background: Limited information exists on how the family unit aids or impedes physical activity (PA) engagement within Hispanic populations. This qualitative study explored family-level influences on PA in dyads of adult Hispanic family members (eg, parent–adult child, siblings, spouses). Methods: In-person interviews and brief surveys were conducted together with 20 dyads lasting 1.5 hours each. Two researchers coded and analyzed text using thematic analysis in NVivo (version 11.0). They resolved discrepancies through consensus and used matrix coding analysis to examine themes by participants’ demographics. Results: The participants were mainly women (70%), from Mexico (61.5%), and they reported low levels of acculturation (87.5%). Themed facilitators for PA included “verbal encouragement,” “help with responsibilities,” “exercising with someone,” and “exercising to appease children.” Themed challenges included “lack of support,” “challenges posed by children,” “sedentary behaviors,” and “competing responsibilities.” Women more so than men described family-level challenges and facilitators, and dyads where both study partners were physically active provided more positive partner interaction descriptions for PA support than other dyads. Conclusions: This study suggests that leveraging family support may be an important approach to promote and sustain PA, and that family-focused interventions should integrate communication-building strategies to facilitate family members’ ability to solicit support from each other.