Balance, which is frequently referred to as our “sixth sense,” depends on input from various body parts to prevent us from falling. It is believed that maintaining equilibrium mostly happens subconsciously. However, humans frequently focus on it like being extra cautious when standing around a hot pot. This is known as conscious movement processing(CMP). The neuromuscular control of balance may change as a result of this increasing reliance on attentional resources. A school of thought suggests that the conscious control of movement and balance is responsible for ‘postural stiffening’ experienced by some people when there is a threat to their balance. The features of postural stiffening are; a simultaneous decrease in the amplitude of sway which is thought to be a result of improved co-contraction of the muscles of the ankle. The intermuscular coherence (IMC) analysis could be used to examine the influence of conscious processing on the neuromuscular control of posture. A study was recently carried out by Li-Juan et al to evaluate the impact of CMP on IMC.
Posture outcomes may vary
This study analyses how the neuromuscular regulation of posture in young, fit adults is affected by circumstances that either encourage or limit conscious movement processing. The control of posture was assessed using the parameters of performance, muscle coordination, and movement automaticity. Thus, we anticipated; an increase in sway amplitude, reduction in movement automaticity and increased beta band IMC in both agonist and antagonist muscle groups. Twelve muscle pairs in the lower leg were examined for intermuscular coherence.
25 adults of age ranging from 18 to 40 years with body mass index between 18 to 27 kg/m² were used for this experiment. It was ensured that they didn’t have any neurological or muscular illnesses. They performed a narrowed two-legged stance on a flat surface wearing flat shoes and looking at the screen in front of them. All the parameters were assessed.
Results showed that there was a rise in sway amplitude and a decrease in complexity and frequency. They increased further in the unstable position. In comparison to the stable situation, a considerable rise in IMC was seen across all frequency bands. When comparing high- to low-CMP, we saw decreased beta band IMC amongst several muscle groups, but these results lost their significance when multiple comparisons were taken into account.
With these findings, medics can explore the effects of CMP on IMC, and across different levels of task difficulty, the current study may ultimately help improve our understanding of how elevated CMP – as often observed in anxious individuals, and clinical populations – contributes to (mal)adaptive changes in postural control
In conclusion, the results show the presence of nerve signals to the muscles of the lower leg during bilateral stance while adjusting CMP and the complexity of the task. Further research into this is needed.