I Lower center of mass creates more stability so how do you explain moving the center of mass upwards increases stability?

AI Thread Summary
In martial arts, raising the arms during movements like kicking shifts the center of mass (COM) upwards, which might seem counterintuitive for stability. However, this action increases the moment of inertia, allowing for better balance control. Maintaining balance relies on adjusting the center of gravity (COG), which is facilitated by arm movement. While a higher COM can reduce stability, it can also lengthen the natural period of oscillation, making movements smoother. Ultimately, the interplay between balance and COG adjustment is crucial for effective performance in martial arts.
John3022
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How is it possible that moving the center of mass upwards increases stability and not the opposite?
When you are doing certain movements in martial arts like kicking, you bring your arms up in order to balance yourself. Bringing your arms upwards also moves the center of mass (COM) upwards but if the COM is higher than the position should be less stable and not more stable. How do you explain the stabilizing effect of moving your COM upwards?
 
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You are increasing your moment of inertia.
 
John3022 said:
How do you explain the stabilizing effect of moving your COM upwards?
Have you ever seen a wire walker (e.g. the Great Wallenda) stroll across a wire with his arms down by his side? BALANCE matters more than COG.

EDIT: Hm ... that was not well put. Yes, balance is what's important, BUT ... you maintain balance by changing you COG, which you cannot do if your arms are by your sides. You have to be able to move your arms around to maintain your COG where it needs to be for you to not fall over.
 
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John3022 said:
When you are doing certain movements in martial arts like kicking, you bring your arms up in order to balance yourself.
Could you show us a specific movement?
How high are the arms brought up (shoulder level or way above)?
 
John3022 said:
How do you explain the stabilizing effect of moving your COM upwards?
Moment of inertia.
For a small boat, raising the centre of mass, lengthens the natural period of oscillation, and so makes it more comfortable, but reduces stability.

Longer pendulums swing slower.
 
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