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Erin Hanlon and Cynthia Bir

Soccer heading has been studied previously with conflicting results. One major issue is the lack of knowledge regarding what actually occurs biomechanically during soccer heading impacts. The purpose of the current study is to validate a wireless head acceleration measurement system, head impact telemetry system (HITS) that can be used to collect head accelerations during soccer play. The HIT system was fitted to a Hybrid III (HIII) head form that was instrumented with a 3-2-2-2 accelerometer setup. Fifteen impact conditions were tested to simulate impacts commonly experienced during soccer play. Linear and angular acceleration were calculated for both systems and compared. Root mean square (RMS) error and cross correlations were also calculated and compared for both systems. Cross correlation values were very strong with r = .95 ± 0.02 for ball to head forehead impacts and r = .96 ± 0.02 for head to head forehead impacts. The systems showed a strong relationship when comparing RMS error, linear head acceleration, angular head acceleration, and the cross correlation values.

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Katrina D. DuBose, Sandra Edwards, Barbara E. Ainsworth, Jared P. Reis and Martha L. Slattery

Background:

Historical physical activity (PA) questionnaires assess relationships between past PA and chronic diseases. The 4-Corner’s Historical Physical Activity Questionnaire (HPAQ) was validated in 78 middle-age women.

Methods:

In 1996 and 1998, women kept PA records (PAR) for four consecutive days while wearing Caltrac accelerometers. In 2001, the same women recalled their past PA levels using the HPAQ. PA levels from the HPAQ were compared to PARs and the Caltrac. Race-adjusted Spearman correlations determined validity.

Results:

Low to modest correlations existed between PA (min/wk and MET-min/wk) from the HPAQ and PARs for moderate (r = 0.16 and 0.14, respectively), vigorous PA (r = 0.26 and 0.27, respectively; P < 0.05) and moderate-vigorous PA (r = 0.20 and 0.17, respectively). Moderate and moderate-vigorous, but not vigorous PA was positively related to energy expenditure expressed as kilocalories (r = 0.23, P < 0.05 and 0.22, −0.03, respectively) or PA volume (MET-min/wk) (r = 0.29, 0.29, P < 0.05 and 0.10, respectively).

Conclusion:

The HPAQ can produce valid estimates of women’s past moderate and vigorous PA levels.

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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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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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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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Steven Baumann and Keith Henschen

In recent years, the academic standards of the collegiate student athlete have become a popular subject within the sociology of sport. In January 1983, the top competitive division of the NCAA voted to make more stringent the academic standards for participants in Division I intercollegiate sports. This was known as Proposal 48, and although the vote was 2 to 1 in favor of it, much criticism was also voiced. This study examines the relationship between the American College Testing Program (ACT) and actual grade point average (GPA) for 753 male and female athletes at the University of Utah during a 10-year period. A secondary purpose was to determine the predictive validity of a predicted GPA formula (PGPA) and high school grade point average (HSGPA) as estimates of actual GPA. Other purposes were to determine the correlation of ACT, PGPA, and HSGPA with regard to gender, race, and sport. Pearson product-moment correlations were utilized to establish relationships between ACT scores, PGPA, and HSGPA with actual GPA. A multiple correlation coefficient was computed and a regression equation was established. In addition, a cross-validation was performed on the existing data. Results indicated that an equation combining ACT and HSGPA is the best predictor for Caucasians, while HSGPA alone is the best predictor for non-Caucasians. Factors other than ACT scores appear to be better predictors of academic success for the student-athlete, thus casting doubt upon the validity of Proposal 48 for the NCAA.

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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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Steven P. Hooker, Anna Feeney, Brent Hutto, Karin A. Pfeiffer, Kerry McIver, Daniel P. Heil, John E. Vena, Michael J. LaMonte and Steven N. Blair

Purpose:

This study was designed to validate the Actical activity monitor in middle-aged and older adults of varying body composition to develop accelerometer thresholds to distinguish between light and moderate intensity physical activity (PA).

Methods:

Nonobese 45 to 64 yr (N = 29), obese 45 to 64 yr (N = 21), and ≥65 yr (N = 23; varying body composition) participants completed laboratory-based sitting, household, and locomotive activities while wearing an Actical monitor and a portable metabolic measurement system. Nonlinear regression analysis was used to identify activity count (AC) cut-points to differentiate between light intensity (<3 METs) and moderate intensity (≥3METs) PA.

Results:

Using group-specific algorithms, AC cut points for 3 METs were 1634, 1107, and 431 for the obese 45 to 64 yr group, nonobese 45 to 64 yr group, and ≥65 yr group, respectively. However, sensitivity and specificity analysis revealed that an AC cut-point of 1065 yielded similar accuracy for detecting an activity as less than or greater than 3 METs, regardless of age and body composition.

Conclusion:

For the Actical activity monitor, an AC cut-point of 1065 can be used to determine light and moderate intensity PA in people ≥45 years of age.

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

Background:

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.

Methods:

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

Results:

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).

Conclusions:

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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Patricia W. Bauer, James M. Pivarnik, Deborah L. Feltz, Nigel Paneth and Christopher J. Womack

Background:

Physical activity (PA) is an important component of a healthy pregnancy and postpartum period. Since prospective PA monitoring throughout gestation is difficult, a valid PA recall tool would be of significant benefit to researchers. The purpose of this study was to evaluate the ability of women to recall their physical activity performed during pregnancy and postpartum, 6 years later.

Methods:

Thirty women participated in an historical PA recall study. Pregnancy PA was monitored carefully via assisted physical activity diary (PAD) 6 years before the current investigation. A Modifiable Activity Questionnaire (MAQ) was used to assess current and past pregnancy PA. The MAQ was administered for each time period in the order of most distant past to most current. Leisure time energy expenditure values (kcal/kg/day) calculated from the PAD and the MAQ were compared.

Results:

MAQ energy expenditure values showed good positive relationships with PAD measures at 20 weeks gestation (r = .57; P < .01), 32 weeks gestation (r = .85; P < .01), and 12 weeks postpartum (r = .86; P < .01). Correlations found were similar to those from previous PA recall and MAQ validation studies using nonpregnant populations.

Conclusions:

The MAQ is an appropriate tool to assess pregnancy and postpartum PA in women 6 years postpartum.