Respiratory components of human postural sway

Area of Science:

• Human physiology
• Biomechanics
• Postural control

Background:

• Postural sway is a critical indicator of balance and the effectiveness of the human postural control system.
• Voluntary and involuntary movements can influence postural stability, but the specific contribution of respiration has been debated.

Purpose of the Study:

• To quantify the effect of respiration on postural sway in healthy individuals.
• To investigate the relationship between respiratory parameters (rate, amplitude) and the magnitude of postural sway.
• To examine the impact of respiration on postural control in both standing and seated positions.

Main Methods:

• Utilized averaging and spectral analysis techniques to assess postural sway.
• Subjects performed voluntarily paced respiration to isolate respiratory effects.
• Measured reaction torque in seated subjects to compare responses.

Main Results:

• A significant portion of postural sway was directly attributable to respiratory activity.
• The contribution of respiration to sway remained relatively constant across a normal range of respiratory rates.
• A linear relationship was observed between respiration amplitude and the magnitude of sway.
• Respiration induced comparable changes in reaction torque in seated individuals.

Conclusions:

• Body movements during paced respiration represent a substantial disturbance to the human postural control system.
• Compensatory hip movements do not effectively mitigate the postural disturbances caused by respiration, contrary to previous suggestions.
• Understanding respiratory influences is crucial for a comprehensive model of human postural control.