Does The Redundancy in Human Body Make Learning Goal-Directed Motor Tasks More Difficult?
: Insights into Establishing an Effective Motor Learning Program
【Supercategory：7. DESCENTE SPORTS SCIENCE Subcategory：7.44 Vol.44】
ABSTRACT
The redundancy in human body is believed to make motor control more complex. However, given the inherent noise in the human control system, the redundancy may allow strategies to reduce the effects of noise during a several goal-directed motor task, making motor execution rather easy. Here I show a case in which experimental reduction of degrees of freedom delays motor learning compared to the normal condition in a non-dominant arm dart throwing task. A total of 21 adult male and female participants were randomly allocated to a shoulder-joint restrained group and a control group and asked to perform 20 throws x 10 sets of a non-dominant arm dart task. The dart landing point and upper-limb kinematics were measured using a 3D motion-capture system. The shortening of the distance between the landing point and target in the control group reached a plateau at approximately the third set, whereas this shortening was delayed in the restrained group: at the third set, the distance between the landing point and target was significantly longer in the restrained group（0.135±0.026m） than in the control group （0.099±0.018 m）．These results suggest that practice methods in which each motor segmented structure （i.e., part?method of learning） is mastered separately can rather delay the learning of goal-directed motor tasks.
DECENTE SPORTS SCIENCE Vol.44/The DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE
The redundancy in human body is believed to make motor control more complex. However, given the inherent noise in the human control system, the redundancy may allow strategies to reduce the effects of noise during a several goal-directed motor task, making motor execution rather easy. Here I show a case in which experimental reduction of degrees of freedom delays motor learning compared to the normal condition in a non-dominant arm dart throwing task. A total of 21 adult male and female participants were randomly allocated to a shoulder-joint restrained group and a control group and asked to perform 20 throws x 10 sets of a non-dominant arm dart task. The dart landing point and upper-limb kinematics were measured using a 3D motion-capture system. The shortening of the distance between the landing point and target in the control group reached a plateau at approximately the third set, whereas this shortening was delayed in the restrained group: at the third set, the distance between the landing point and target was significantly longer in the restrained group（0.135±0.026m） than in the control group （0.099±0.018 m）．These results suggest that practice methods in which each motor segmented structure （i.e., part?method of learning） is mastered separately can rather delay the learning of goal-directed motor tasks.
DECENTE SPORTS SCIENCE Vol.44/The DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE
| Researcher | Natsuki Sado |
|---|---|
| University or institution | University of Tsukuba |
Keywords
Motor control, Darts, Coordination, UCM hypothesis, part?method of learning