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
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
José I. Recio-Rodríguez, Natalia Sanchez-Aguadero, Emiliano Rodríguez-Sánchez, Vicente Martinez-Vizcaino, Carlos Martin-Cantera, Maria C. Patino-Alonso, Jose A. Maderuelo-Fernandez, Manuel A. Gómez-Marcos, Luis Garcia-Ortiz and for the EVIDENT Group
This study determined the relationship between self-reported and objective measurements of physical activity with adiposity markers in a random sample of community-dwelling older adults. The sample included 439 individuals over 65 years (age 71.1 ± 7.8; 54.2% women). Regular physical activity information was collected using self-reported (questionnaire, 7-day-PAR) and objective measurements (accelerometer ActiGraph GT3X) over 7 days. Anthropometric parameters included body mass index, body fat percentage, and waist circumference. The number of patients considered active was 28% according to the results of 7-day PAR, and 69% according to objective measures of accelerometry. With every daily increase of 10 min of sedentary activity, the BMI, body fat percentage, and waist circumference values increased by 0.04 units, 0.14%, and 0.14 cm, respectively. According to the accelerometry data, being active was a protective factor for presenting obesity criteria (OR = 0.34, CI 95% 0.19–0.59). Objective but non self-reported physical activity was associated with adiposity markers in older adults.
Bettina Bringolf-Isler, Urs Mäder, Nicole Ruch, Susi Kriemler, Leticia Grize and Charlotte Braun-Fahrländer
Accurately measuring children’s physical activity and their sedentary behavior is challenging. The present study compared 189 parental responses to a questionnaire surveying physical activity and sedentary behavior of children aged 6–14 years, to accelerometer outputs and time activity diaries for the same group. Responses were analyzed taking age, sex and maternal education into account. Correlation coefficients between questionnaire reports and accelerometer-based physical activity across all age groups were acceptable (up to r = .55). Yet, adjustment for age markedly attenuated these associations, suggesting concomitant influences of biological and behavioral processes linked to age. The comparisons of general time indications in the questionnaire with 24h-diary records suggested that parents tended to under- and over-report single activities, possibly due to social desirability. We conclude that physical activity questionnaires need to be designed for specific age groups and be administered in combination with objective measurements.
Jefferson Fagundes Loss, Edgar Santiago Wagner Neto, Tatiane Borsoi de Siqueira, Aline Dill Winck, Laura Silveira de Moura and Luiz Carlos Gertz
Trunk-flexor muscle strength plays a fundamental role in athletic performance, but objective measurements are usually obtained using expensive and nonportable equipment, such as isokinetic dynamometers. The aim of this study was to assess the concurrent validity of a portable, one-dimensional, trunk-flexor muscle strength measurement system (Measurement System) that uses calibrated barbells and the reliability of the measurements obtained using the Measurement System, by conducting test–retests. As a complementary assessment, the measurements obtained during a maximum contraction test performed by a group of 15 subjects were also recorded. Four conditions were assessed: repeatability, time reproducibility, position reproducibility, and subject reproducibility. The results demonstrate that both the concurrent validity and the measured reliability (intraclass correlation coefficient > .98) of the Measurement System are acceptable. The Measurement System provides valid and reliable measures of trunk-flexor muscle strength.
Yvonne Michael, Tracey Beard, Dongseok Choi, Stephanie Farquhar and Nichole Carlson
There is a need for greater understanding of how perceptions and objective measures of the physical environment influence physical activity among seniors. The goal of this study was to examine the degree of association between perceived and objective characteristics of the neighborhood environment and the relation of each type of measurement to neighborhood walking in older adults. Data on self-reported frequency of walking in the neighborhood and perceived measures of neighborhood environment from 105 older adults were linked to objective measures assessed by geographic information systems and an audit instrument. Perceived and objective measurements of the built environment exhibited a low degree of agreement (kappas: <.20). After adjustment for education, age, and gender, presence of a mall was positively associated with neighborhood walking in both the objective and perceived models.
Patricia A. Sharpe, Sara Wilcox, Laura J. Rooney, Donna Strong, Rosie Hopkins-Campbell, Jean Butel, Barbara Ainsworth and Deborah Parra-Medina
Objective measurement of physical activity with accelerometers is a challenging task in community-based intervention research. Challenges include distribution of and orientation to monitors, nonwear, incorrect placement, and loss of equipment. Data collection among participants from disadvantaged populations may be further hindered by factors such as transportation challenges, competing responsibilities, and cultural considerations.
Research staff distributed accelerometers and provided an orientation that was tailored to the population group. General adherence strategies such as follow-up calls, daily diaries, verbal and written instructions, and incentives were accompanied by population-specific strategies such as assisting with transportation, reducing obstacles to wearing the accelerometer, tailoring the message to the participant population, and creating a nonjudgmental environment.
Sixty women asked to wear the Actigraph GT1M returned the accelerometer, and 57 of them provided sufficient data for analysis (at least 10 hours a day for a minimum of 4 days) resulting in 95% adherence to the protocol. Participants wore the accelerometers for an average of 5.98 days and 13.15 hours per day.
The high accelerometer monitoring adherence among this group of economically disadvantaged women demonstrates that collection of high-quality, objective physical activity data from disadvantaged populations in field-based research is possible.
Sze Yen Tan, Marijka Batterham and Linda Tapsell
Knowing the total energy expenditure (TEE) of overweight adults is important for prescribing weight loss interventions. However, objective measurements of TEE may not always be readily available and can be expensive. This study aimed to investigate the validity of RT3 accelerometers in predicting the TEE of sedentary overweight adults, and to identify any sensitivity to anthropometric changes.
The analysis used data from a 12-week weight loss study. At baseline and 12-week, TEE was predicted using RT3 accelerometers during whole room calorimeter stays. Bias between 2 methods was compared at and between the baseline and 12-week measurement points. Multiple regression analyses of TEE data were conducted.
Predicted and measured values for TEE were not different at baseline (P = .677) but were significantly different after weight loss (P = .007). However, the mean bias between methods was small (<100 kcal/d) and was not significantly different between 2 time-points. RT3 activity counts explained an additional 2% of the variation in TEE at 12-week but not at baseline.
RT3 accelerometers are not sensitive to body composition changes and do not explain variation in TEE of overweight and obese individuals in a sedentary environment.
Sarah J. Fraser, Justin J. Chapman, Wendy J. Brown, Harvey A. Whiteford and Nicola W. Burton
The aim of this study was to assess the feasibility of using questionnaires and accelerometers to measure physical activity and sedentary behavior among inpatient adults with mental illness.
Participants completed a physical activity and sitting time questionnaire and wore an accelerometer for 7 consecutive days. Feasibility was assessed in terms of participant engagement, self-reported ease/difficulty of completing study components, extreme self-report data values and adherence to accelerometer wear time criteria. Ease/difficulty ratings were examined by level of distress.
177 inpatients were invited to the study, 101 completed the questionnaires and 36 provided valid accelerometry data. Participants found it more difficult to complete sitting time and physical activity questionnaires than to wear the accelerometer during waking hours (z = 3.787, P < .001; z = 2.824, P = .005 respectively). No significant differences were found in ease/difficulty ratings by level of distress for any of the study components. Extreme values for self-reported sitting time were identified in 27% of participants.
Inpatient adults with mental illness can engage with self-report and objective methods of measuring physical activity and sedentary behavior. They were initially less willing to participate in objective measurement, which may however be more feasible than self-report measures.
Rebecca A. Abbott, Doune Macdonald, Smita Nambiar and Peter S.W. Davies
Objective measurement of daily steps was used to assess whether children (n = 2,076) in Years 1, 5 and 10 who reported walking to or from school were more active and more likely to reach recommended step targets than those who were driven or took public transport to school. Walking to school was associated with higher school-day steps in older children (16,238 vs 15,275 for Year 5 male p < .05, 13,521 vs 12,502 for Year 5 female p < .01, 12,109 vs 11,373 for Year 10 female p < .05). The proportion of children who met recommended step thresholds was higher in those who walked to school compared with those who took motorized transport, and this was significant for Year 5 females (71.7% vs 54.5%, p < .01). This study suggests that walking to school for older children has potential to contribute significantly to daily activity levels and increases the likelihood of attaining recommended step targets. These data should encourage public policy and those concerned with the built environment to provide and support opportunities for walking to school.
Suzy Lai Wong, Rachel Colley, Sarah Connor Gorber and Mark Tremblay
Actical accelerometer thresholds have been derived to enable objective measurement of time spent performing sedentary activity in children and adolescents, but not adults. Thus, the purpose of this study was to determine Actical accelerometer sedentary activity thresholds for adults.
Data were available from 3187 participants aged 6 to 79 years from a preliminary partial dataset of the Canadian Health Measures Survey, who wore an Actical for 7 days. Step count data were used to evaluate the use of 50, 100, and 800 counts per min (cpm) as sedentary activity thresholds. Minutes when no steps were recorded were considered minutes of sedentary activity.
The use of higher cpm thresholds resulted in a greater percentage of sedentary minutes being correctly classified as sedentary. The percentage of minutes that were incorrectly classified as sedentary was substantially higher when using a threshold of 800 cpm compared with 50 or 100 cpm. Results were similar for children, adolescents, and adults.
These findings suggest that a threshold of 100 cpm is appropriate for classifying sedentary activity of adults when using the Actical. As such, wear periods with minutes registering less than 100 cpm would be classified as time spent performing sedentary activity.