A conditioned patellar tendon reflex paradigm was used to study the contributions of crossed spinal and supraspinal inputs to the output of the alpha motoneuron pool in children with and without developmental coordination disorders. The basic patellar tendon reflex response was exaggerated in children with developmental coordination disorders. Crossed spinal and supraspinal influences on the excitability of the alpha motoneuron pool were similar in both groups of children. However, there was evidence of exaggerated crossed spinal and supraspinal inputs onto the alpha motoneuron pool in individual children with developmental coordination disorder.
Harriet G. Williams and Jeanmarie R. Burke
Steven R. Passmore, Jeanmarie Burke and Jim Lyons
A discrete aiming head movement task was developed to replicate Fitts’ movement paradigm. Movement time (MT) differences between young (age range 24-29 years, n = 8) and old adults (age range 75-85 years, n = 8) were examined. Cervical spine (CS) range of motion (ROM) was recorded. A head mounted motion capture device was used to evaluate task performance. Three amplitudes and three target widths generated nine indexes of difficulty (IDs). Global ROM was decreased in old adults. The ID and MT relationship was maintained with age; however, old adults were slower, more variable, and more affected by ID. Variations in target size were used as the accuracy variable for both groups. As target size increased, the old population overshot their endpoint. These data support the hypothesis that, besides musculoskeletal slowing with age, there may be age-related deterioration of central processing, planning, or perception mechanisms.
Lawrence W. Judge and Jeanmarie R. Burke
To determine the effects of training sessions, involving high-resistance, low-repetition bench press exercise, on strength recovery patterns, as a function of gender and training background.
The subjects were 12 athletes (6 males and 6 females) and age-matched college students of both genders (4 males and 4 females). The subjects completed a 3-wk resistance training program involving a bench press exercise, 3 d/wk, to become familiar with the testing procedure. After the completion of the resistance training program, the subjects, on three consecutive weeks, participated in two testing sessions per week, baseline session and recovery session. During the testing sessions, subjects performed fve sets of the bench press exercise at 50% to 100% of perceived fve repetition maximum (5-RM). Following the weekly baseline sessions, subjects rested during a 4-, 24-, or 48-h recovery period. Strength measurements were estimates of one repetition maximum (1-RM), using equivalent percentages for the number of repetitions completed by the subject at the perceived 5-RM effort of the bench press exercise.
The full-factorial ANOVA model revealed a Gender by Recovery Period by Testing Session interaction effect, F(2, 32) = 10.65; P < .05. Among male subjects, decreases in estimated 1-RM were detected at the 4- and 24-h recovery times. There were no differences in muscle strength among the female subjects, regardless of recovery time.
For bench press exercises, using different recovery times of 48 h for males and 4 h for females may optimize strength development as a function of gender.