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Bo Fernhall, A. Lynn Millar, Kenneth H. Pitetti, Terri Hensen and Mathew D. Vukovsch

We cross validated the 20-m shuttle run test of aerobic capacity in children and adolescents with mild and moderate mental retardation (MR) using the population specific formula of Fernhall et al. (1998). Nine boys and 8 girls (age = 13.7 yr) completed a maximal treadmill protocol (measured V̇O2peak) and a 20-m shuttle run (predicted V̇O2peak). The measured peak oxygen consumption (V̇O2peak) was 39.4 ml kg-1 min-1. The relationship between measured and predicted V̇O2peak was r = .86 with an SEE of 6.2 ml kg-1 min-1. Multiple regression and Bland-Altman analyses showed that there was little bias, but the Bland-Altman analysis indicated highly variable limits of agreement (Bland & Altman 1986). Thus, the traditional approach (regression analysis) to concurrent validity revealed that the 20-m shuttle run is a valid indicator of V̇O2peak in these participants. The accuracy of prediction (Bland & Altman, 1986), however, was lower than expected in a population without MR.

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David E. Conroy, Robert W. Motl and Evelyn G. Hall

Self-presentation has become an increasingly popular topic in exercise and sport psychology, yet few instruments exist to measure this construct. This paper describes two validation studies conducted on the Self-Presentation in Exercise Questionnaire (SPEQ), a paper-and-pencil instrument based on Leary and Kowalski’s (1990) two-component model of impression management. The SPEQ was designed to assess impression motivation (IM) and impression construction (IC) in exercise environments. The first study employed exploratory factor analysis to reduce a pool of 125 content-representative items to a subset of 41 items forming the hypothesized two-factor model of IM and IC. In the second study, the 41 items were further reduced using exploratory and confirmatory factor analyses in separate samples, and the reduced SPEQ also conformed to the IM and IC factor structure. The second study also provided initial evidence to support the convergent and discriminant validity of the SPEQ with theoretically salient constructs such as body surveillance, perceived physical ability, physical self-presentation confidence, social desirability, and social physique anxiety.

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Jonathan G. Beckwith, Jeffrey J. Chu and Richard M. Greenwald

Although the epidemiology and mechanics of concussion in sports have been investigated for many years, the biomechanical factors that contribute to mild traumatic brain injury remain unclear because of the difficulties in measuring impact events in the field. The purpose of this study was to validate an instrumented boxing headgear (IBH) that can be used to measure impact severity and location during play. The instrumented boxing headgear data were processed to determine linear and rotational acceleration at the head center of gravity, impact location, and impact severity metrics, such as the Head Injury Criterion (HIC) and Gadd Severity Index (GSI). The instrumented boxing headgear was fitted to a Hybrid III (HIII) head form and impacted with a weighted pendulum to characterize accuracy and repeatability. Fifty-six impacts over 3 speeds and 5 locations were used to simulate blows most commonly observed in boxing. A high correlation between the HIII and instrumented boxing headgear was established for peak linear and rotational acceleration (r 2 = 0.91), HIC (r 2 = 0.88), and GSI (r 2 = 0.89). Mean location error was 9.7 ± 5.2°. Based on this study, the IBH is a valid system for measuring head acceleration and impact location that can be integrated into training and competition.

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Elena Bergamini, Pélagie Guillon, Valentina Camomilla, Hélène Pillet, Wafa Skalli and Aurelio Cappozzo

The proper execution of the sprint start is crucial in determining the performance during a sprint race. In this respect, when moving from the crouch to the upright position, trunk kinematics is a key element. The purpose of this study was to validate the use of a trunk-mounted inertial measurement unit (IMU) in estimating the trunk inclination and angular velocity in the sagittal plane during the sprint start. In-laboratory sprint starts were performed by five sprinters. The local acceleration and angular velocity components provided by the IMU were processed using an adaptive Kalman filter. The accuracy of the IMU inclination estimate and its consistency with trunk inclination were assessed using reference stereophotogrammetric measurements. A Bland-Altman analysis, carried out using parameters (minimum, maximum, and mean values) extracted from the time histories of the estimated variables, and curve similarity analysis (correlation coefficient > 0.99, root mean square difference < 7 deg) indicated the agreement between reference and IMU estimates, opening a promising scenario for an accurate in-field use of IMUs for sprint start performance assessment.

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Karen L. Moy, Robert K. Scragg, Grant McLean and Harriette Carr


This study validated the short- and long-form New Zealand Physical Activity Questionnaires (NZPAQ-SF and NZPAQ-LF) against heart-rate monitoring (HRM) with individual calibration.


A multiethnic sample (N = 180), age 19 to 86 y, underwent HRM for 3 consecutive days while simultaneously completing physical activity (PA) logs.


Both NZPAQs showed significant (p < .001) correlations to HRM data for brisk walking (r = .27–.43), vigorous-intensity PA (r = .27–.35), and total PA (r = .25; 95% CI, 0.10-0.40), whereas moderate-intensity PA was substantially overreported (mean = 157-199 min). Although the NZPAQ-LF performed better for brisk walking and vigorous-intensity PA, the NZPAQs were strongly correlated (r = .61 and r = .52, respectively, p < .0001). European/Other participants demonstrated the most accurate PA recall of total PA on both NZPAQs (r = .36−.41, p < .01).


The NZPAQs are acceptable instruments for measuring adult PA levels and produce similar results. Substituting culturally specific examples of PAs on the NZPAQs and their accompanying show cards could potentially improve PA recall for Maori and Pacific people.

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Gregg Afman, Richard M. Garside, Neal Dinan, Nicholas Gant, James A. Betts and Clyde Williams

Current recommendations for nutritional interventions in basketball are largely extrapolated from laboratory-based studies that are not sport-specific. We therefore adapted and validated a basketball simulation test relative to competitive basketball games using well-trained basketball players (n = 10), then employed this test to evaluate the effects of two common preexercise nutritional interventions on basketball-specific physical and skilled performance. Specifically, in a randomized and counterbalanced order, participants ingested solutions providing either 75 g carbohydrate (sucrose) 45 min before exercise (Study A; n = 10) or 2 × 0.2 g·kg−1 sodium bicarbonate (NaHCO3) 90 and 20 min before exercise (Study B; n = 7), each relative to appropriate placebos (H2O and 2 × 0.14 g·kg−1 NaCl, respectively). Heart rate, sweat rate, pedometer count, and perceived exertion did not systematically differ between the 60-min basketball simulation test and competitive basketball, with a strong positive correlation in heart rate response (r = .9, p < .001). Preexercise carbohydrate ingestion resulted in marked hypoglycemia (< 3.5 mmol·l−1) throughout the first quarter, coincident with impaired sprinting (+0.08 ± 0.05 second; p = .01) and layup shooting performance (8.5/11 versus 10.3/11 baskets; p < .01). However, ingestion of either carbohydrate or sodium bicarbonate before exercise offset fatigue such that sprinting performance was maintained into the final quarter relative to placebo (Study A: –0.07 ± 0.04 second; p < .01 and Study B: -0.08 ± 0.05 second; p = .02), although neither translated into improved skilled (layup shooting) performance. This basketball simulation test provides a valid reflection of physiological demands in competitive basketball and is sufficiently sensitive to detect meaningful changes in physical and skilled performance. While there are benefits of preexercise carbohydrate or sodium bicarbonate ingestion, these should be balanced against potential negative side effects.

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Jeffrey B. Driban, Nicole Cattano, Easwaran Balasubramanian, Michael R. Sitler, Mamta Amin, Joseph Glutting and Mary F. Barbe

Context: To better understand why a knee develops osteoarthritis after joint trauma we need to assess the local biochemical changes. Unfortunately, it is challenging to obtain synovial fluid from a knee with no effusion. Objective: To describe the authors' protocol for aspirating synovial fluid from noneffused knees. Second, they demonstrate the validity of this method by evaluating the relationships between normalized and raw biomarker concentrations among knees with effusion (undergoing a traditional aspiration) and without effusion (requiring a saline-assisted aspiration). Design: Validation study based on secondary analyses from 2 cohort studies. Setting: Outpatient orthopedic clinic and basic-science laboratory. Participants: Participants had moderate to severe radiographic knee osteoarthritis (n = 15 with and 11 without effusion) and no osteoarthritis or effusion (n = 4). Interventions: The same orthopedic surgeon performed all synovial-fluid joint aspirations, including saline-assisted aspirations. Main Outcome Measures: The authors used multiplex enzyme-linked immunosorbent assays to determine 7 synovial-fluid biomarker concentrations. They then calculated correlations between raw and normalized (to total synovial-fluid protein content) biomarker concentrations. Results: The authors excluded 1 sample collected with a saline-assisted aspiration because it contained blood. Normalized biomarker concentrations had positive associations with raw biomarker concentrations (r = .77-99), with the exception of interleukin-13 and interleukin-1Β among knees that underwent a saline-assisted aspiration. Excluding interleukin-1Β, associations between normalized and raw biomarker concentrations were consistent between knees that had a saline-assisted or traditional aspiration. Conclusions:Saline-assisted aspiration is a valid technique for assessing the local biochemical changes in knees without effusion.

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Sofiya Alhassan, John R. Sirard, Laura B. F. Kurdziel, Samantha Merrigan, Cory Greever and Rebecca M. C. Spencer


The purpose of this study was to cross-validate previously developed Actiwatch (AW; Ekblom et al. 2012) and AcitGraph (AG; Sirard et al. 2005; AG-P, Pate et al. 2006) cut-point equations to categorize free-living physical activity (PA) of preschoolers using direct observation (DO) as the criterion measure. A secondary aim was to compare output from the AW and the AG from previously developed equations.


Participants’ (n = 33; age = 4.4 ± 0.8 yrs; females, n=12) PA was directly observed for three 10-min periods during the preschool-day while wearing the AW (nondominant wrist) and AG (waist). Device specific cut-points were used to reduce the AW-E (Ekblom et al. 2012) and AG (AG-S, Sirard et al. 2005; AG-P, Pate et al. 2006) data into intensity categories. Spearman correlations (rsp) and agreement statistics were used to assess associations between the DO intensity categories and device data. Mixed model regression was used to identify differences in times spent in activity intensity categories.


There was a significant correlation between AW and AG output across all data (rsp = 0.41, p < .0001) and both were associated with the DO intensity categories (AW: rsp = 0.47, AG: rsp = 0.47; p < .001). At the individual level, all devices demonstrated relatively low sensitivity but higher specificity. At the group level, AW-E and AG-P provided similar estimates of time spent in moderate-to-vigorous PA (MVPA, AW-E: 4.7 ± 4.1, AG-P: 4.4 ± 3.3), compared with DO (5.1 ± 3.5). Conclusion: The AW-E and AG-P estimated times spent in MVPA were similar to DO, but the weak agreement statistics indicate that neither device cut-point equations provided accurate estimates at the individual level.

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Maria Hagströmer, Barbara E. Ainsworth, Lydia Kwak and Heather R. Bowles


The quality of methodological papers assessing physical activity instruments depends upon the rigor of a study’s design.


We present a checklist to assess key criteria for instrument validation studies.


A Medline/PubMed search was performed to identify guidelines for evaluating the methodological quality of instrument validation studies. Based upon the literature, a pilot version of a checklist was developed consisting of 21 items with 3 subscales: 1) quality of the reported data (9 items: assess whether the reported information is sufficient to make an unbiased assessment of the findings); 2) external validity of the results (3 items: assess the extent to which the findings are generalizable); 3) internal validity of the study (9 items: assess the rigor of the study design). The checklist was tested for interrater reliability and feasibility with 6 raters.


Raters viewed the checklist as helpful for reviewing studies. They suggested minor wording changes for 8 items to clarify intent. One item was divided into 2 items for a total of 22 items.


Checklists may be useful to assess the quality of studies designed to validate physical activity instruments. Future research should test checklist internal consistency, test-retest reliability, and criterion validity.

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Dany Lafontaine and Mario Lamontagne

Many human activities, particularly sporting skills, occur over large distances. But technical limitations have forced biomechanists to conduct studies only on portions of such skills. In this paper we present the design and validation of a mobile data collection system composed of a camera cart that allows the tracking of athletes along a larger portion of their movements. A key feature of this system is that it requires only a small field of view to record and analyze joint motions. The validation of this method was conducted with three approaches. For all approaches, intermarker distances obtained from real measures were compared to those obtained from digitized video data. In all three experiments, the results proved to be within the accepted error range of 5%. The net differences between measured values and digitized values ranged from 0.8 to 3 mm, while the relative errors ranged from 0.2 to 6%. This first experimentation using a mobile camera array to collect and reconstruct biomechanical data has proven to be valid and worth pursuing for recording and analyzing ice hockey skating.