Although not well validated, physicians frequently use subjective estimates of exercise ability to assess clinical status and therapeutic results. This study employed a standardized questionnaire and cardiopulmonary exercise test to compare the results of subjective estimates by 211 patients (mean age 13.9 yrs) with objective measurements of exercise ability. Questionnaire data correlated with measured maximal oxygen consumption. Individuals thought to be below average had a maximal oxygen consumption of 21±6 ml/kg/min. Those thought to have average fitness had a maximal oxygen consumption of 26±8 ml/kg/min, and those thought to be above average had a maximal oxygen consumption of 30±7 ml/kg/min. There was a great degree of overlap and scatter of these data, however, such that questionnaire data significantly overestimated exercise ability in 67% and underestimated it in 3% of the subjects. In only 30% of the subjects did the subjective estimate of exercise ability correspond with objectively measured exercise ability. It was concluded that subjective estimates are unreliable and should not be used in assessing the functional status of an individual patient, but subjective estimates may give some idea of objective capabilities in large population studies.
Gerald Barber and Charles T. Heise
William L. Haskell
This symposium addressed the ongoing development of new technologies for the objective measurement of physical activity and diet and efforts to provide best practice guidelines for scientists developing, evaluating and using existing and new technologies for the objective measurement of physical activity. The research projects discussed and the workshop overview presented are components of the Genes, Environment, and Health Initiative (GEI) of the National Institutes of Health. The rationale, plans and progress of the GEI physical activity and diet initiative were presented. Detailed presentations described 2 projects focused on the use of mobile phone based systems designed to collect, process and store data; 1 uses multiple wireless accelerometers to detect body movement and the other uses a camera built into a mobile phone and advanced software to quantify dietary intake. Given the rapid development of new accelerometer-based physical activity measurement devices and analytical approaches, it is important that best practices be used by scientists and practitioners using theses devices. An overview of a “best practices” workshop held in July 2009 was presented. The presentations and discussions during this symposium made evident the progress, potential and challenges of implementing advanced technologies to enhance the measurement of physical activity and diet.
Miguel Ángel de la Cámara, Sara Higueras-Fresnillo, David Martinez-Gomez and Óscar L. Veiga
education, or measurement day. In the same way, a previous study that analyzed moderator effects of sex on interday reliability using objective measurement did not find differences ( Tudor-Locke et al., 2005 ). Measurement days constitute an important factor to consider when PA is evaluated by objective
Nicholas D. Gilson, Caitlin Hall, Andreas Holtermann, Allard J. van der Beek, Maaike A. Huysmans, Svend Erik Mathiassen and Leon Straker
in 2011 36 with the majority published over the last 3 years (ie, 2015–2018). 20 – 35 , 37 , 38 Twelve studies were located in Denmark, 23 – 34 all but one 22 accessing 2 large national data sets (ie, New method for Objective Measurements of physical Activity in Daily living [NOMAD], Danish
Miguel A. de la Cámara, Sara Higueras-Fresnillo, Verónica Cabanas-Sánchez, Kabir P. Sadarangani, David Martinez-Gomez and Óscar L. Veiga
well as low precision, error, and bias. 17 It has been observed that they generally underestimate sedentary time in comparison with accelerometer data (>2 h/d), 18 – 25 showing weak to moderate correlations when they are compared with objective measurements. 18 – 21 , 25 The Global Physical Activity
Anne Martin, Mhairi McNeill, Victoria Penpraze, Philippa Dall, Malcolm Granat, James Y. Paton and John J. Reilly
The Actigraph is well established for measurement of both physical activity and sedentary behavior in children. The activPAL is being used increasingly in children, though with no published evidence on its use in free-living children to date. The present study compared the two monitors in preschool children. Children (n 23) wore both monitors simultaneously during waking hours for 5.6d and 10h/d. Daily mean percentage of time sedentary (nontranslocation of the trunk) was 74.6 (SD for the Actigraph and 78.9 (SD 4.3) for activPAL. Daily mean percentage of time physically active (light intensity physical activity plus MVPA) was 25.4 (SD for the Actigraph and 21.1 (SD 4.3) for the activPAL. Bland-Altman tests and paired t tests suggested small but statistically significant differences between the two monitors. Actigraph and activPAL estimates of sedentary behavior and physical activity in young children are similar at a group level.
Carla Elane Silva dos Santos, Sofia Wolker Manta, Guilherme Pereira Maximiano, Susana Cararo Confortin, Tânia Rosane Bertoldo Benedetti, Eleonora d’Orsi and Cassiano Ricardo Rech
Background: To examine the level of physical activity and sedentary behavior (SB), measured with accelerometers, in older adults from a city in southern Brazil according to sociodemographic and health characteristics. Methods: The sample consisted of 425 older adults (≥63 y) from the EpiFloripa Aging Study. Light physical activity (LPA), moderate to vigorous physical activity (MVPA), and SB were measured with accelerometers over a period of 7 days. Results: The older adults spent two-thirds of the time of use in SB, one-third in LPA, and only 2.1% (95% confidence interval, 1.8–2.2) in MVPA. In the final adjusted model, lower levels of MVPA were observed for women, as well as higher SB and lower LPA and MVPA for those with higher age. There were also trends toward prolonged SB and lower LPA when participants had a higher educational level and toward lower MVPA with higher body mass index. Conclusions: Constant monitoring of physical activity levels and SB using objective measures is recommended and interventions should be directed at the groups most exposed to excessive SB and low levels of MVPA.
Cheryl L. Addy, Jennifer L. Trilk, Marsha Dowda, Won Byun and Russell R. Pate
The purpose of this study was to determine the minimum number of days of accelerometry required to estimate accurately MVPA and total PA in 3- to 5-year-old children. The study examined these metrics for all days, weekdays, and in-school activities. Study participants were 204 children attending 22 preschools who wore accelerometers for at least 6 hr per day for up to 12 days during most waking hours. The primary analysis considered the intraclass correlation coefficient (ICC) for each metric to estimate the number of days required to attain a specified reliability. The ICC estimates are 0.81 for MVPA-all days, 0.78 for total PA-all days, 0.83 for MVPA weekdays, 0.80 for total PA-weekdays, 0.81 for in-school MVPA, and 0.84 for in-school total PA. We recommend a full seven days of measurement whenever possible, but researchers can achieve acceptable reliability with fewer days, as indicated by the Spearman-Brown prophecy: 3–4 days for any weekday measure and 5–6 days for the all-days measures.
Derek M.D. Silva, Roy Bower and William Cipolli III
between objective measurements of athletes and the subjective assessment of those athletes by scouts. One would expect that both objective and subjective assessments of an athlete’s body are predictors of scouts’ overall evaluation. One would also expect that subjective assessments of athlete’s bodies are
Philippa M. Dall, Dawn A. Skelton, Manon L. Dontje, Elaine H. Coulter, Sally Stewart, Simon R. Cox, Richard J. Shaw, Iva Čukić, Claire F. Fitzsimons, Carolyn A. Greig, Malcolm H. Granat, Geoff Der, Ian J. Deary, Sebastien F.M. Chastin and On behalf of the Seniors USP Team
different constructs of physical behaviors compared with objective monitors ( Troiano, McClain, Brychta, & Chen, 2014 ). Using objective measurement of PA and SB in large-scale studies incurs practical and pragmatic challenges, different from the use of self-report, and often requires informed decisional