Motor Control Performance During Rapid Voluntary Movements of Elbow and Knee

ABSTRACT

Knowledge of motor control differences during rapid goal-directed movements of the upper and lower limbs could be useful in improving rehabilitation protocols. The authors investigated performance and control differences between elbow and knee joints and between different contraction types (concentric vs. eccentric) during rapid movements under externally applied load. There were no significant differences in performance and control with respect to joint (elbow vs. knee) but the performance during concentric contractions was better than eccentric for both the joints. The findings indicate that despite anatomical and functional differences, the CNS is finely tuned for both the joints to maximize the efficiency of movement during a dynamic environment, but there are differences in control strategies between the 2 contraction types.

Keywords:

• concentric versus eccentric
• goal-directed
• motor performance
• rapid contractions
• single-joint

ACKNOWLEDGEMENTS

The authors thank Dr. Tom Krouskop, Stefan Madansingh, Dr. Robert Ploutz-Snyder, Dhruti Patel, Phillippe Dentino, Sophia Beltran, and Leana Karkour for their help at various phases of the project. The authors are also grateful to Dr. B. C. Lee and Dr. T. A. Thrasher for their thoughtful review of this manuscript.

FUNDING

This study was supported in part by a grant from the National Aeronautics and Space Administration through NASA #102912 to Dr. William H. Paloski.