Medicine and Health Sciences Commons^™

Effects Of Lift Velocity On Muscle Activation During Leg Extension, Stephen C. Glass

Stephen C Glass

Abstract: It is not known if manipulating velocity within a prescribed resistance training mode will improve muscle activation. Muscle activations of the Rectus Femoris (RF), Vastus Lateralis (VL), Vastus Medialis (VM) and Bicep Femoris (BF) were examined during a leg extension exercise at 3 different velocities on 15 subjects (10men, 5 female, Age = 21.5 ± 1.8 yrs, Height = 171.2 ± 12.5 cm, Mass = 75.5 ± 16.3 kg). Trials of 1 set of 10 repetitions at 60% of 1RM, were performed at 15, 30 and 60º/s. Bipolar surface electrodes were placed over the BF, RF, VL, and VM. …

Emg Remains Fractionated In Parkinson's Disease, Despite Practice-Related Improvements In Performance, D. Flament, D. Vaillancourt, T. Kempf, K. Shannon, D. Cross

Timothy Kempf

Objective: We studied the ability of patients with Parkinson's disease to improve their performance in a motor task requiring both speed and accuracy in the execution of elbow flexion movements. Our goal was to investigate the changes in electromyographic activity associated with the changes in movement performance.

Methods: Eleven patients on anti-Parkinsonian medication were tested. The patients were selected for being bradykinetic, having little or no resting tremor or dyskinesias, and being in stages II or III of the Hoehn and Yahr rating scale.

Results: The untrained patients displayed multiple bursts of agonist activity, characteristic of Parkinsonian EMG recordings. All …