Does Body Postural Configuration Affect Upper Limb Performance During Point-to-Point Hand Movements?

Area of Science:

• Motor control and biomechanics
• Human factors and ergonomics

Background:

• Postural configuration is essential for preparing movement.
• The influence of different body postures on motor performance remains unclear.

Purpose of the Study:

• To investigate how body posture (sitting vs. standing) affects fast and accurate planar point-to-point hand movements.
• To determine if arousal manipulation influences motor performance in different postures.

Main Methods:

• Twenty-three healthy adults performed a Go/No-go task involving repetitive point-to-point hand movements.
• Arousal levels were manipulated using a sham threat of electrical stimulation.
• Recorded data included upper limb kinematics, center of pressure displacement, and galvanic skin responses across four conditions (sitting/standing with/without arousal manipulation).

Main Results:

• Arousal levels differed significantly between conditions with and without arousal manipulation.
• No significant difference in arousal levels was observed between sitting and standing postures.
• Center of pressure displacement onset was earlier in standing conditions compared to sitting.
• No significant differences in upper limb performance were found between postures or due to arousal manipulation.

Conclusions:

• Under the tested experimental conditions, body posture (sitting vs. standing) does not appear to affect upper limb motor performance.
• Arousal manipulation did not influence upper limb performance in this study.
• Future research could explore other types of movements or populations.