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Whole-body and segment angular momentum during 90-degree turns
Luis A Nolasco1, Anne K Silverman2, Deanna H Gates3
1School of Kinesiology, University of Michigan, Ann Arbor, MI, USA.
Gait & Posture
|February 19, 2019
Summary
Healthy individuals use whole-body angular momentum to maintain balance during turns. Different body segments contribute to this momentum, especially the outside leg and head/trunk, aiding in dynamic balance.
Area of Science:
- Biomechanics
- Human locomotion
- Motor control
Background:
- Turning is a common daily activity that presents a balance challenge due to its asymmetric nature.
- Maintaining dynamic balance during such movements is crucial for preventing falls.
Purpose of the Study:
- To investigate how healthy individuals maintain dynamic balance during 90-degree turns compared to straight-line walking.
- To quantify whole-body angular momentum during turning and identify the contributions of different body segments.
Main Methods:
- Kinematic data of 16 healthy individuals were collected during straight-line walking and 90-degree turns.
- Whole-body and segment angular momenta were calculated in three planes of motion.
- The relative contributions of legs, arms, pelvis, and head/trunk to whole-body angular momentum were analyzed.
Main Results:
- Whole-body angular momentum differed significantly during turning versus straight-line walking across all motion planes.
- Turning required generating angular momentum at initiation and counteracting it at the end, with transverse momentum always matching the turn direction.
- The outside leg and head/trunk segments were primary contributors to frontal and transverse plane whole-body angular momentum.
Conclusions:
- Body segment contributions to angular momentum are critical for maintaining balance during turning.
- This understanding can inform the development of rehabilitation strategies for individuals with turning difficulties or impaired balance.
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