Postural control and ventilatory drive during voluntary hyperventilation and carbon dioxide rebreathing

Abstract

The present study sought to establish links between hyperventilation and postural stability. Eight university students were asked to stand upright under two hyperventilation conditions applied randomly: (1) a metabolic hyperventilation induced by 5 min of hypercapnic-hyperoxic rebreathing (CO(2)-R); and, (2) a voluntary hyperventilation (VH) of 3 min imposed by a metronome set at 25 cycles per min. Recordings were obtained with eyes open, with the subjects standing on a force plate over 20-s periods. Ventilatory response, displacements in the centre of pressure in both the frontal and sagittal planes and fluctuations in the three planes of the ground reaction force were monitored in the time and frequency domains. Postural changes related to respiratory variations were quantified by coherence analysis. Myoelectric activities of the calf muscles were recorded using surface electromyography. Force plate measurements revealed a reduction in postural stability during both CO(2)-R and VH conditions, mainly in the sagittal plane. Coherence analysis provided evidence of a ventilatory origin in the vertical ground reaction force fluctuations during VH. Electromyographic analyses showed different leg muscles strategies, assuming the existence of links between the control of respiration and the control of posture. Our results suggest that the greater disturbing effects caused by voluntary hyperventilation on body balance are more compensated when respiration is under automatic control. These findings may have implications for understanding the organisation of postural and respiratory activities and suggest that stability of the body may be compromised in situations in which respiratory demand increases and requires voluntary control.

Proprioceptive Changes Impair Balance Control in Individuals with Chronic Obstructive Pulmonary Disease

“…When the respiratory function of the diaphragm is challenged, e.g. when respiratory demand increases, its postural function may also be challenged, resulting in a negative effect upon postural control [26], [27]. Healthy individuals are able to compensate for increases in respiratory demand using multi-segmental control [28].…”

Abdominal muscle activity during breathing with and without inspiratory and expiratory loads in healthy subjects

“…The breathing movements of rib cage and abdomen generate a cyclical disturbance to the trunk stability and the body equilibrium (Hodges et al, 2002). Despite healthy subjects are capable of actively compensate for the quiet breathing, postural control is compromised when the respiratory demand increases and requires voluntary control (David et al, 2012;Kuznetsov and Riley, 2012). This increased descending respiratory drive attenuates the postural activity of diaphragm and TrA muscles (Hodges et al, 2001).…”

Postural- and respiratory-related activities of abdominal muscles during post-exercise hyperventilation

“…In an upright stance at rest, it is well known that quiet breathing perturbs body balance in the sagittal and frontal planes, and that the effects of compensatory motions of the trunk and lower limbs are more pronounced in the sagittal plane [2]. When the respiratory demand increases, the deeper and faster rib cage movements lead to greater postural sways, which seem to be more compensated by the postural control system when respiration is under automatic control, suggesting the existence of functional links between respiration and postural control centres [2,3].…”