Children and adolescents with intellectual disability (ID) exhibit a mixture of cognitive, motor, and psychosocial limitation. Identifying specific inadequacies in motor proficiency in youth with ID would improve therapeutic management to enhance functional capacity and health-related physical activity. The purpose of this study was to initiate descriptive data collection of gross motor skills of youth with ID and compare those skills with competency norms. The Bruininks-Oseretsky Test of Motor Proficiency (BOT-2) was used to measure 6 items for balance (BAL), 5 items for upper limb coordination (ULC), and 6 items for bilateral coordination (BLC) of 123 males (ages 8–18) with ID but without Down syndrome. The authors performed 2,840 assessments (10–32 for each item); 944, 985, and 913 for BAL, ULC, and BLC, respectively. Mean scores for all age groups for BAL, ULC, and BLC were consistently below BOT-2 criteria. Overall motor skills of males with ID are below the competence expected for children and adolescents without disabilities.
Ken Pitetti, Ruth Ann Miller and Michael Loovis
David C. Berry and Michael G. Miller
Thomas G. Ribble, Michael H. Santare and Freeman Miller
Finite element models of the proximal femur at birth, 2 years of age, and at 8 years of age were constructed to investigate stress patterns under different loading conditions. These loading conditions represent typical activities of a normal developing child and abnormal activity associated with muscle spasticity. The hypothesis is that the shear stresses in the growth plate correlate with the neckshaft angle as associated with valgus and normal development. Loads for the finite element models were derived from a separate muscle model used to calculate the forces across the hip joint for an arbitrary subject and activity. Results show there is an inverse relationship between the relative magnitude of the shear stress in the growth plate and the developing neck-shaft angle. The relatively high shear stresses generated by normal activity in the 2-year-old’s growth plate correlate with the decrease in neck-shaft angle that accompanies normal development. Alternatively, lower shear stresses are generated in the growth plate by loading conditions representing spasticity. These lower magnitude shear stresses correlate with a valgus deformity, which is often observed clinically.
Ken Pitetti, Ruth Ann Miller and E. Michael Loovis
Male youth (8–18 years) with intellectual disability (ID) demonstrate motor proficiency below age-related competence capacities for typically developing youth. Whether below-criteria motor proficiency also exists for females with ID is not known. The purpose of this study was to determine if sex-specific differences exist in motor proficiency for youth with ID. The Bruininks-Oseretsky Test of Motor Proficiency was used to measure motor proficiency: six items for upper limb coordination, seven items for balance, and six items for bilateral coordination. One hundred and seventy-two (172) males and 85 females with ID but without Down syndrome were divided into five age groups for comparative purposes: 8–10, 11–12, 13–14, 15–16, and 17–21 years. Males scored sufficiently higher than females to suggest that sex data should not be combined to established Bruininks-Oseretsky Test of Motor Proficiency standards for upper limb coordination, balance, and bilateral coordination subtests.
Michael G. Miller, David C. Berry, Susan Bullard and Roger Gilders
Land and aquatic plyometrics have clinical relevance for exercise, sport performance, and rehabilitation, yet study is limited comparing both.
To compare the effects of land-based and aquatic-based plyometric-training programs on performance variables, muscle soreness, and range of motion (ROM).
Aquatic facility and biomechanics laboratory.
Forty subjects randomly assigned to 3 groups: land (n = 13), water (n = 13), and control (n = 14).
Main Outcome Measures:
Performance variables, muscle soreness, and ROM were measured before and after an 8-week training period. An analysis of covariance (ANCOVA) and a Bonferroni post hoc test determined significance.
ANCOVA revealed significant differences between groups with respect to plantar-flexion ROM (P < .05). Paired t test determined that the aquatic group significantly increased muscle power pretest to posttest (P < .05).
Results indicate that aquatic plyometric training can be an alternative approach to enhancing performance.
Michael G. Miller, Christopher C. Cheatham, William R. Holcomb, Rosealin Ganschow, Timothy J. Michael and Mack D. Rubley
No direct research has been conducted on the relationship between subcutaneous tissue thickness and neuromuscular electrical stimulation (NMES).
The purpose of this study was to determine the effects of subcutaneous tissue thickness on NMES amplitude and NMES force production of the quadriceps.
Simple fixed design, testing the independent variable of subcutaneous thickness (skinfold) groups with the dependent variables of NMES amplitude and force production.
Athletic Training Laboratory.
29 healthy women.
NMES to produce at least 30% of maximal voluntary isometric contractions (MVIC) of the quadriceps.
Main Outcome Measure:
Maximal NMES amplitude and percentage of MVIC using NMES.
A significant skinfold category difference F2,28 = 3.92, P = .032 on NMES amplitude was found. Post hoc revealed the thinnest skinfold category tolerated less amplitude compared to the thickest category. A significant correlation was found between NMES amplitude skinfold category R = .557, P = .002.
Higher NMES amplitudes are needed for the thickest skinfold category compared to the thinnest skinfold category.