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Pedro C. Hallal, Eduardo Simoes, Felipe F. Reichert, Mario R. Azevedo, Luiz R. Ramos, Michael Pratt and Ross C. Brownson

Purpose:

To evaluate the validity and reliability of the telephone-administered long IPAQ version.

Methods:

The questionnaire was administered by telephone to adults on days 1 and 6. On day 1, the same questionnaire was administered by face-to-face interview, and accelerometers were delivered to subjects. Reliability was measured by comparing data collected using the telephone questionnaire on days 1 and 6. Validity was measured by comparing the telephone questionnaire data with (a) face-to-face questionnaire and (b) accelerometry.

Results:

Data from all instruments were available for 156 individuals. The Spearman correlation coefficient for telephone interview reliability was 0.92 for the leisure-time section of IPAQ, and 0.87 for the transport-related section of IPAQ. The telephone interview reliability kappa was 0.78. The Spearman correlation between the telephone-administered and the face-to-face questionnaire was 0.94 for the leisure-time and 0.82 for the transport-related section. The kappa was 0.69. There was a positive association between quartiles of accelerometer data and total telephone-administered IPAQ score (P < .001). The Spearman correlation was 0.22.

Conclusions:

The telephone-administered IPAQ presented almost perfect reliability and very high agreement with the face-to-face version. The agreement with accelerometer data were fair for the continuous score, but moderate for the categorical physical activity variables.

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Ryu Nagahara, Alberto Botter, Enrico Rejc, Masaaki Koido, Takeshi Shimizu, Pierre Samozino and Jean-Benoit Morin

Purpose:

To test the concurrent validity of data from 2 different global positioning system (GPS) units for obtaining mechanical properties during sprint acceleration using a field method recently validated by Samozino et al.

Methods:

Thirty-two athletes performed maximal straight-line sprints, and their running speed was simultaneously measured by GPS units (sampling rate: 20 or 5 Hz) and either a radar or laser device (devices taken as references). Lower-limb mechanical properties of sprint acceleration (theoretical maximal force, theoretical maximal speed, maximal power) were derived from a modeling of the speed–time curves using an exponential function in both measurements. Comparisons of mechanical properties from 20- and 5-Hz GPS units with those from reference devices were performed for 80 and 62 trials, respectively.

Results:

The percentage bias showed a wide range of overestimation or underestimation for both systems (-7.9% to 9.7% and -5.1% to 2.9% for 20- and 5-Hz GPS), while the ranges of its 90% confidence limits for 20-Hz GPS were markedly smaller than those for 5-Hz GPS. These results were supported by the correlation analyses.

Conclusions:

Overall, the concurrent validity for all variables derived from 20-Hz GPS measurements was better than that obtained from the 5-Hz GPS units. However, in the current state of GPS devices’ accuracy for speed–time measurements over a maximal sprint acceleration, it is recommended that radar, laser devices, and timing gates remain the reference methods for implementing the computations of Samozino et al.

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Jennifer L. Copeland, Kent C. Kowalski, Rachel M. Donen and Mark S. Tremblay

Background:

To accommodate the need for longitudinal physical activity research, we developed the Physical Activity Questionnaire for Adults (PAQ-AD). The PAQ-AD is an adult version of the PAQ-C and PAQ-A questionnaires which were developed for older children and adolescents, respectively.

Methods:

Two studies assessed the convergent validity of the PAQ-AD using a series of self-report tools and direct measurement of physical activity.

Results:

In the first sample (N = 247), the PAQ-AD was significantly related to a series of self-report tools (r = 0.53 to 0.64). In the second sample (N = 184), the PAQ-AD was significantly related to the self-report tools (r = 0.56 to 0.63), a physical activity recall interview (r = 0.24), and to direct measurements of physical activity (r = 0.26 to 0.43).

Conclusion:

These results provide preliminary validity evidence for the PAQ-AD and suggest the PAQ “family” of questionnaires might be advantageous for longitudinal research assessing physical activity from childhood to adulthood.

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Randall J. Bergman, David R. Bassett Jr. and Diane A. Klein

Background:

This 2-part study examined validity of selected motion sensors for assessing physical activity in older adults residing in assisted-living communities.

Methods:

Twenty-one older adults (mean age = 78.6 ± 13.1 years) wore the StepWatch 3 Step Activity Monitor (SW3) and the Yamax Digi-Walker SW-200 pedometer (DW). Part I compared accuracy of these devices for measuring steps taken over 161 m. Part II compared devices over a 1-day (24-hour) period.

Results:

In part I, the DW recorded 51.9% (r 2 = –.08, P = .75) and the SW3 recorded 102.6% (r 2 = .99, P < .001) of steps. In part II, the DW measured significantly fewer steps (1587 ± 1057 steps) than did the SW3 (6420 ± 3180 steps).

Conclusions:

The SW3 pedometer was more accurate in counting steps and recorded higher 24-hour step counts than the DW pedometer. Thus, the SW3 is a valid research instrument for monitoring activity in the assisted-living population.

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Luca Ruggiero, Susan Dewhurst and Theodoros M. Bampouras

Leg stiffness is an important performance determinant in several sporting activities. This study evaluated the criterion-related validity and reliability of 2 field-based leg stiffness devices, Optojump Next® (Optojump) and Myotest Pro® (Myotest) in different testing approaches. Thirty-four males performed, on 2 separate sessions, 3 trials of 7 maximal hops, synchronously recorded from a force platform (FP), Optojump and Myotest. Validity (Pearson’s correlation coefficient, r; relative mean bias; 95% limits of agreement, 95%LoA) and reliability (coefficient of variation, CV; intraclass correlation coefficient, ICC; standard error of measurement, SEM) were calculated for first attempt, maximal attempt, and average across 3 trials. For all 3 methods, Optojump correlated highly to the FP (range r = .98–.99) with small bias (range 0.91–0.92, 95%LoA 0.86–0.98). Myotest demonstrated high correlation to FP (range r = .81–.86) with larger bias (range 1.92–1.93, 95%LoA 1.63–2.23). Optojump yielded a low CV (range 5.9% to 6.8%), high ICC (range 0.82–0.86), and SEM ranging 1.8–2.1 kN/m. Myotest had a larger CV (range 8.9% to 13.0%), moderate ICC (range 0.64–0.79), and SEM ranging from 6.3 to 8.9 kN/m. The findings present important information for these devices and support the use of a time-efficient single trial to assess leg stiffness in the field.

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Alexander Allan Wetten, Marijka Batterham, Sze Yen Tan and Linda Tapsell

Background:

With physical inactivity inextricably linked to the increasing prevalence of obesity, there is a need for validated methods that measure free-living energy expenditure (EE) within sedentary environments. While accelerometers enable these measurements, few studies have compared device accuracy in such settings. The aim of this study was to investigate the relative validity of the Actigraph, RT3 and SenseWear Armband (SWA).

Methods:

Twenty-three (11 male, 12 female) participants (age: 25.3 ± 6.3 yr; BMI: 22.6 ± 2.7) wore 3 accelerometers at designated sites during a 4-hour stay in the Whole Room Calorimeter (WRC). Participants performed 2 10-minute bouts of light-intensity exercise (stepping and stationary cycling) and engaged in unstructured sedentary activities. EE estimated by accelerometers was compared with WRC EE derived from measurements of gaseous exchange.

Results:

The Actigraph and SWA both accurately estimated EE during the stepping exercise. EE estimated by the RT3 during stepping was significantly lower than the WRC value (31.2% ± 15.6%, P < .001). All accelerometers underestimated cycling and unstructured activity EE over the trial period (P < .001).

Conclusions:

The Actigraph and SWA are both valid tools for quantifying EE during light-intensity stepping. These results provide further valuable information on how accelerometer devices may be appropriately used.

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Au Bich Thuy, Leigh Blizzard, Michael Schmidt, Pham Hung Luc, Costan Magnussen and Terence Dwyer

Background:

The Global Physical Activity Questionnaire (GPAQ) was developed as an improvement of the International Physical Activity Questionnaire (IPAQ) for use in cross-cultural settings. This study compared the reliability and validity of GPAQ and IPAQ in Vietnam.

Methods:

251 adults were randomly selected from a population-based survey (n = 1978) of noncommunicable disease risk factors. GPAQ and IPAQ were administered on 2 occasions. Participants wore pedometers and logged their physical activity (PA) for 7 consecutive days.

Results:

Test-retest correlations of GPAQ measurements differed for participants (n = 153) with stable work patterns (work PA r = .43, total PA r = .39) and those (n = 98) with unstable work patterns (work PA r = −0.02, total PA r = −0.05). IPAQ measurements did not differ in this way. GPAQ reliability was poorer for transport (GPAQ r = .25, IPAQ r = .60) and for leisure (GPAQ r = .21, IPAQ r = .45) PA. GPAQ estimates of total PA for participants with stable work patterns were moderately correlated with IPAQ total PA (r = .32), steps per day (r = .39), and PA log (r = .31).

Conclusions:

The modifications made when designing GPAQ improved its reliability for persons with stable work patterns, but at the expense of poorer reliability for persons with more variable PA. GPAQ did not have superior validity to IPAQ.

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David A. Rowe, Thomas D. Raedeke, Lenny D. Wiersma and Matthew T. Mahar

The purpose of the study was to investigate the measurement properties of questionnaires associated with the Youth Physical Activity Promotion (YPAP) model. Data were collected from 296 children in Grades 5–8 using several existing questionnaires corresponding to YPAP model components, a physical activity questionnaire, and 6 consecutive days of pedometer data. Internal validity of the questionnaires was tested using confirmatory factor analyses, and external validity was investigated via correlations with physical activity and body composition. Initial model fit of the questionnaires ranged from poor to very good. After item removal, all scales demonstrated good fit. Correlations with percentage body fat and objectively measured physical activity were low but in the theoretically predicted direction. The current study provides good internal validity evidence and acceptable external validity evidence for a brief set of questionnaire items to investigate the theoretical basis for the YPAP model.

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Matthew D. Portas, Jamie A. Harley, Christopher A. Barnes and Christopher J. Rush

Purpose:

The study aimed to analyze the validity and reliability of commercially available nondifferential Global Positioning System (NdGPS) devices for measures of total distance during linear, multidirectional and soccer-specific motion at 1-Hz and 5-Hz sampling frequencies.

Methods:

Linear (32 trials), multidirectional (192 trials) and soccer-specific courses (40 trials) were created to test the validity (mean ± 90% confidence intervals), reliability (mean ± 90% confidence intervals) and bias (mean ± 90% confidence intervals) of the NdGPS devices against measured distance. Standard error of the estimate established validity, reliability was determined using typical error and percentage bias was established.

Results:

The 1-Hz and 5-Hz data ranged from 1.3% ± 0.76 to 3.1% ± 1.37 for validity and 2.03% ± 1.31 to 5.31% ± 1.2 for reliability for measures of linear and soccer-specific motion. For multidirectional activity, data ranged from 1.8% ± 0.8 to 6.88% ± 2.99 for validity and from 3.08% ± 1.34 to 7.71% ± 1.65 for reliability. The 1-Hz underestimated some complex courses by up to 11%.

Conclusions:

1-Hz and 5-Hz NdGPS could be used to quantify distance in soccer and similar field-based team sports. Both 1-Hz and 5-Hz have a threshold beyond which reliability is compromised. 1-Hz also underestimates distance and is less valid in more complex courses.

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Maude Bastien, Hélène Moffet, Laurent Bouyer, Marc Perron, Luc J. Hébert and Jean Leblond

The Star Excursion Balance Test (SEBT) has frequently been used to measure motor control and residual functional deficits at different stages of recovery from lateral ankle sprain (LAS) in various populations. However, the validity of the measure used to characterize performance—the maximal reach distance (MRD) measured by visual estimation—is still unknown.

Objectives:

To evaluate the concurrent validity of the MRD in the SEBT estimated visually vs the MRD measured with a 3D motion-capture system and evaluate and compare the discriminant validity of 2 MRD-normalization methods (by height or by lower-limb length) in participants with or without LAS (n = 10 per group).

Results:

There is a high concurrent validity and a good degree of accuracy between the visual estimation measurement and the MRD gold-standard measurement for both groups and under all conditions. The Cohen d ratios between groups and MANOVA products were higher when computed from MRD data normalized by height.

Conclusion:

The results support the concurrent validity of visual estimation of the MRD and the use of the SEBT to evaluate motor control. Moreover, normalization of MRD data by height appears to increase the discriminant validity of this test.