Wearable accelerometer-based activity monitors (AMs) are used to estimate energy expenditure and ground reaction forces in free-living environments, but a lack of standardized calibration and data reporting methods limits their utility. The objectives of this study were to (1) design an inexpensive and easily reproducible AM testing system, (2) develop a standardized calibration method for accelerometer-based AMs, and (3) evaluate the utility of the system and accuracy of the calibration method. A centrifuge-type device was constructed to apply known accelerations (0-8g) to each sensitive axis of 30 custom and two commercial AMs. Accelerometer data were recorded and matrix algebra and a least squares solution were then used to determine a calibration matrix for the custom AMs to convert raw accelerometer output to units of g’s. Accuracy was tested by comparing applied and calculated accelerations for custom and commercial AMs. AMs were accurate to within 4% of applied accelerations. The relatively inexpensive AM testing system (< $100) and calibration method has the potential to improve the sharing of AM data, the ability to compare data from different studies, and the accuracy of AM-based models to estimate various physiological and biomechanical quantities of interest in field-based assessments of physical activity.
Crystal L. Coolbaugh and David A. Hawkins
basketball magazine that arguably embodied the intersection between the culture of hip-hop music and young players in the National Basketball Association (NBA) that emerged in the 1990s, he was ready to embrace his passion for all sports. Accepting the editor-in-chief position at Bleacher Report, a high
Nicolas Robin, Lucette Toussaint, Stéphane Sinnapah, Olivier Hue and Guillaume R. Coudevylle
, 2015 ; O’Reilly & Spruijt-Metz, 2013 ). Recent studies have shown that texting increases certain domains of self-reported physical activity ( Antoine Parker & Ellis, 2016 ; Kim & Glanz, 2013 ; Muller, Khoo, & Morris, 2016 ). For example, Robin et al. ( 2017 ) showed that guided imagery texts
Anthony Rossi, Tina Claiborne and Jamie Fetter
proximal aorta. 4 , 5 This case study reports on a rare event in which an athlete with BAV disease remained undiagnosed until his college freshman year. The American Heart Association (AHA) recommends review of a careful personal and family history as well as a focused physical examination prior to
Allana G.W. LeBlanc and Ian Janssen
We examined differences between objective (accelerometer) and subjective (self-report) measures of moderate-to-vigorous physical activity (MVPA) in youth. Participants included 2761 youth aged 12–19 years. Within each sex and race group, objective and self-reported measures of MVPA were poorly correlated (R 2 = .01–.10). Self-reported MVPA values were higher than objective values (median: 42.4 vs. 15.0 min/d). 65.4% of participants over-reported their MVPA by 35 min/d. The difference between self-reported and objective measures was not influenced by sex, age, or race. There was, however, a systematic difference such that inactive participants over-reported their MVPA to the greatest extent.
Yannis Manios, Anthony Kafatos and George Markakis
Heart rate monitoring was used to evaluate the validity and reliability of 2 proxy report measures in assessing moderate to vigorous physical activity (MYPA) in 39 six-year-old children. Significant positive correlations were found between the proxy measures and corresponding heart rate data for school hours and leisure time, respectively (teacher reports, r = .58, p < .001; parent reports, r = .71 to .81, p < .001), but these decreased when each proxy measure was compared with heart rate data collated over a 3-day period (teacher reports, r = .40, p = .01; parent reports, r = .68, p < .001). Repeating the measurements gave a positive test-retest reliability coefficient of r = .84 (p < .001) and r = .64 (p < .001) for teacher and parent reports, respectively. The results indicate that both proxy reports can be useful tools in assessing MVPA in young children but that leisure-time activity reports provide a better basis for extrapolation in assessing weekly MVPA.
Satya S. Jonnalagadda, Dan Benardot and Marian N. Dill
This study examines the degree of under-reporting of energy intake by elite, female gymnasts, and the impact this predicted under-reporting has on associated macro and micro nutrient intake. Twenty-eight female U.S. national team artistic gymnasts participated in the study. Dietary intake was assessed using 3-day food records, and the degree of under-reporting was predicted from the ratio of reported energy intake (EI) to predicted basal metabolic rate (BMRestd), using the standards described by Goldberg et al. (10). Sixty-one percent of the subjects had an EI/BMRestd ratio of < 1.44, and were classified as under-reporters. The under-reporters had higher BMIs and percent body fat, and lower reported total energy intakes than the adequate energy reporters. Additionally, under-reporting of energy intake had a significant impact on reported micro nutrient intake. The under-reporting of energy intake seen in these subjects has an impact on the reported intake of macro and micro nutrients that can influence the interpretation of the nutritional status of these athletes and the strategy for nutrition intervention. Therefore, when assessing dietary intakes of elite gymnasts, some means of determining the accuracy of the reported energy and nutrient intake should be employed to more accurately identify the true nutritional problems experienced by these elite athletes.
Greet Cardon, Ilse De Bourdeaudhuij, Dirk De Clercq, Renaat Philippaerts, Stefanie Verstraete and Elisatbeth Geldhof
The present study investigates whether physical fitness, physical activity, and determinants of physical activity are associated with reports of back and neck pain in children. A total of 749 children (mean age: 9.7 years ± 0.7) were evaluated, using a standardized physical fitness test (Eurofit), a physical activity questionnaire, and a pain prevalence questionnaire. Results indicate that physical fitness levels are not associated with back pain reports, but pain reports are lower in girls reporting higher frequencies of moderate physical activity and better estimates for attitude toward physical activity. Therefore, in girls, increased levels of physical activity might contribute to better back health.
Gershon Tenenbaum, Michael Lloyd, Grace Pretty and Yuri L. Hanin
A study was carried out to examine the ability of equestrians to accurately report precompetition emotions and thoughts across varying time delays (3,7, and 14 days) after competition. Forty male and female dressage riders were randomly divided into two equal groups: participants who watched their videotaped precompetition routine before responding to the items, and participants who visualized the precompetition routine without any external aid. Each rider completed several questionnaires which measured emotions, items related to horses, and an open-ended question on thoughts and emotions at that moment. After a delay of 3,7, and 14 days, the riders were asked to respond to the same questions after imagining themselves preparing for the competition. Repeated-measures MANOVA indicate that though some decrease in emotional intensity was noted for some emotions in the retrospective report, the stability of reporting precompetition emotions was very high in all delay periods. The horse related items were reported particularly accurately. Watching the videotape did not improve the accuracy of the report. Content analysis, however, indicated that when measurement consisted of free report, many emotions and thoughts were added or omitted in the delayed modes. Ericsson and Simon’s (1980, 1984) verbal reports and protocol analysis conceptualization is used to elaborate upon these results.