The muscle fiber force–length relationship has been explained in terms of the cross-bridge theory at the sarcomere level. In vivo, for a physiologically realistic range of joint motion, and therefore range of muscle fiber lengths, only part of the force–length curve may be used; that is, the section of the force– length curve expressed can vary. The purpose of this study was to assess the accuracy of a method for determining the expressed section of the force– length curve for biarticular muscles. A muscle model was used to simulate the triceps surae muscle group. Three model formulations were used so that the gastrocnemius operated over different portions of the force–length curve: the ascending limb, the plateau region, and the descending limb. Joint moment data were generated for a range of joint configurations and from this simulated data the region of the force– length relationship that the gastrocnemius muscle operated over was successfully reconstructed using the algorithm of Herzog and ter Keurs (1988a). Further simulations showed that the correct region of the force–length curve was accurately reconstructed even in the presence of random and systematic noise generated to reflect the effects of sampling errors, and incomplete muscle activation.
Samantha L. Winter and John H. Challis
Hyun-Kyoung Oh, Dong-Chul Seo and Francis M. Kozub
The purpose of this study was to explore the original version of Mitchell and Hastings’s (1998) Emotional Reaction to Challenging Behavior Scale (ERCBS) and estimate validity and reliability of a revised version containing 29 items. The Emotional Reaction to Challenging Behavior Scale–Korean (ERCBS-K) was studied using 445 in-service physical educators (228 females; 217 males). Data were collected using onsite administration as well as mail survey administration procedures. Confirmatory and exploratory factor analyses results supported a five-factor, 28-item scale (ERCBS-K). Acceptable internal consistency coefficients were found for each of the subscales of the ERCBS-K (Cronbach’s alpha ranged from 0.71 to 0 .87).
Bo Fernhall and Garth T. Tymeson
This study evaluated the concurrent validity of the 300-yard and the 1.5-mile run with a group of mildly mentally retarded (MR) adults. The subjects, 15 healthy MR adults (M age = 29.5 + 5.6 yrs, M IQ = 60), underwent a maximal treadmill test utilizing a walking protocol, with heart rate and oxygen consumption data collected every minute. They also completed a 300-yard and a 1.5-mile run. The order of testing was counterbalanced. The results indicated that these subjects exhibited very poor cardiovascular fitness levels, with a mean V̇O2max of 28.1 ml•kg-1•min-1 and mean run times of 98.9 sec and 21.1 min for the 300-yard and the 1.5-mile runs, respectively. The correlation between V̇O2max and the 1.5-mile run was –.88, and the correlation for the 300-yard run and V̇O2max was –.71. However, partial correlations indicated that when the effect of height and weight were held constant, only the correlation between V̇O2max and the 1.5-mile run remained significant whereas that between V̇O2max and the 300-yard run dropped. Consequently, the 1.5-mile run appears to be a valid indicator of cardiovascular fitness for these adults with MR, but the 300 yard run is not.
Myriam Guerra, Kenneth H. Pitetti and Bo Fernhall
The purpose of this study was to determine if the regression formula developed for the 20-m shuttle run test (20 MST) for children and adolescents with mild mental retardation (MR), used to predict cardiovascular fitness (V̇O2peak), is valid for adolescents with Down syndrome (DS). Twenty-six adolescents (mean age = 15.3 ± 2.7 yr) with DS (15 males, 11 females) completed a maximal treadmill protocol (measured V̇O2peak) and a 20 MST (predicted V̇O2peak). There was a significant difference (p < .01) between the means of the measured (25.5 ± 5.2 ml·kg-1-·min-1) and the predicted (33.5 ± 3.9 ml·kg-1·min-1) V̇O2peak, respectively. In addition, there was a low relationship between measured and predicted values (r = .54). The results of this study indicate that the regression formula developed for children and adolescents with MR to predict V̇O2peak was not valid in this sample of adolescents with DS.
Nancy D. Groh and Greggory M. Hundt
, a self-efficacy tool developed and validated to explore student self-efficacy ratings in injury assessment, preventative injury care, and therapeutic modalities over a 1-year period specific to gender found significant increases in self-efficacy scores throughout the study period across component
Sergio Jiménez-Rubio, Archit Navandar, Jesús Rivilla-García and Victor Paredes-Hernández
the high incidence, there have been many validated posthamstring strain injury rehabilitation models proposed in the literature, principally based on evaluations and preventive and performance models in the clinical and analytical field. These include the Askling L-protocol, 11 the active knee
Sherry L. Folsom-Meek and Terry L. Rizzo
The purpose of this study was to assess validity and reliability of the Physical Educators’ Attitude Toward Teaching Individuals with Disabilities III (PEATID III; Rizzo, 1993) for future professionals. Participants (N = 3,464) were undergraduate students enrolled in the introductory adapted physical education course at 235 colleges and universities. Construct validity was obtained through principal components analysis with oblique rotation and supported by principal components analysis with varimax rotation. Results showed that PEATID III measures three factors: (a) outcomes of teaching students with disabilities in regular classes, (b) effects on student learning, and (c) need for more academic preparation to teach students with disabilities. Reliability, as estimated through coefficient alpha, was .88 for the total scale and .71 or greater for each of the disability subscales.
Manuel Trinidad-Fernández, Manuel González-Sánchez and Antonio I. Cuesta-Vargas
understand the movement inside the body with a coordinate transform system to set the scapula in space could provide useful insights. We validated a new method, which combined ultrasound imaging with the signal provided by a 3-dimensional electromagnetic sensor in an anatomical model. 6 This appears to be
Robert W. Cox, Rodrigo E. Martinez, Russell T. Baker and Lindsay Warren
assessment. Various applications have been validated as alternatives to inclinometer measurements in the knee. 6 The Clinometer Smartphone Application™ produced by Plaincode App Development has been found reliable for measuring shoulder ROM, 7 but it lacks validation for use in the ankle. Inclinometry has
Scott W. Cheatham and Russell Baker
clinically relevant method of measuring the mechanical properties of 2 different types of precut RockTape tape (Implus, LLC, Durham, NC) at common elongation lengths and to establish the methodology for future validation research on this testing method. 6 Methods This controlled study was conducted in a