Kinematics and muscle activity of the head, lumbar and knee joints during 180° turning and sitting down task in older adults.
BACKGROUND
The "180° turning and sitting down task" is a very conscious movement that requires focusing on turning at the exact moment, and very few studies address on this topic in older adults. The purpose of the study was to compare kinematics and electromyography of the head, lumbar and knee joints during 180°turning in older and young adults.


METHODS
Twenty older adults and 20 younger adults were assessed. A 16-channel telemetry electromyography system with electrogoniometers and an inclinometer were used to record the head, lumbar and knee joint kinematic and electromyography data during the 180° turning. This movement had been further divided into 4 phases (braking, mid-stance, swing, and terminal loading) for analysis.


RESULTS
There were significant differences in the joint displacement and muscular activity among the different phases. Comparison between groups showed that the older adults group had less lateral lumbar flexion, less knee flexion and lower velocity of the head and knee flexion compared to young adults during turning. The electromyography data of the left biceps femoris, left gastrocnemius and left erector spinae muscles in the older adults group showed significantly higher levels than in the young adults.


CONCLUSIONS
Older adults need to adjust velocities of moving joints and increase the extensor synergy muscles of the back and the stance leg to provide posture stability. Kinematics and neuromuscular modulations of the head, lumbar and knee are required according to the various phases of the turn movements and change with aging.
Department of Physical Therapy, Medicine & Nursing College, Hungkuang University, Taichung, Taiwan. Electronic address: kfc@sunrise.hk.edu.tw.
Fang-Chuan
FC
Kuo
Department of Physical Therapy, Medicine & Nursing College, Hungkuang University, Taichung, Taiwan.
Chang-Zern
CZ
Hong
Department of Biomedical Engineering, Hungkuang University, Taichung, Taiwan.
Ben-Yi
BY
Liau
D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D001696:Biomechanical Phenomena / Q000502:physiology; D004576:Electromyography; D005260:Female; D006257:Head / Q000502:physiology*; D006801:Humans; D007719:Knee Joint / Q000502:physiology*; D007866:Leg / Q000502:physiology; D008159:Lumbar Vertebrae / Q000502:physiology*; D008297:Male; D009068:Movement / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D016059:Range of Motion, Articular; D013647:Task Performance and Analysis; D016138:Walking / Q000502:physiology; D055815:Young Adult
Electromyography; Head; Kinematics; Lumbar; Older adults; Turning