Center of Mass: The Core Variable of Movement

Center of Mass: The Core Variable of Movement

Climbing movement is often described in vague terms like “good body positioning” or “efficient technique.”
Mechanically, all climbing boils down to one thing:

Movement = controlling your Center of Mass (CoM) within a changing force environment.

Once you understand how the CoM behaves, you understand:

  • why some positions feel heavy
  • why certain moves must be dynamic
  • why tiny adjustments suddenly make you stable
  • why elite climbers look motionless even during hard sequences
  • why strength feels different depending on your body geometry

This is the fundamental mechanic behind every technique in climbing.

1. What the Center of Mass Actually Is

The CoM is not a point in your belly or chest.
It is the weighted average of your entire body mass, and it moves every time any limb moves.

The CoM behaves like an independent physical object:

  • it follows inertia
  • it has its own trajectory
  • it responds to gravity
  • forces you generate act on it
  • it dictates balance and load distribution

Your body moves around your CoM more than your CoM moves around your body.

2. You Can Only Create Force When the CoM Is in the Right Zone

Hands and feet don’t generate usable force on their own.
They generate force only when the CoM is positioned so the force vector can transfer effectively.

If the CoM is outside the usable force zone:

  • you slip
  • holds feel worse
  • moves feel heavier
  • arms carry too much load
  • technique breaks down

Skilled climbers place their CoM before they pull, push, or reach.
Beginners move their limbs first and hope the CoM follows.

3. CoM Position Determines Whether a Move Must Be Static or Dynamic

A move can be done statically only if:

  • the CoM stays within the base of support
  • friction and geometry allow slow movement
  • the CoM path does not exceed the force limits

If that is impossible, the move must be dynamic.

Dynamic movement becomes necessary when:

  • the CoM must travel outside the stable zone
  • you need momentum to keep contact
  • you cannot maintain friction if you move slowly
  • footholds do not allow gradual loading
  • the body cannot support the CoM through the middle of the move

Dynamic vs. static is not a style difference.
It’s a geometric requirement dictated by where your CoM needs to go.

4. Why Moves Feel “Heavy” or “Light”

A movement feels heavy when:

  • the CoM is far from the wall
  • the CoM creates a large rotational torque around the shoulders
  • the legs cannot support the CoM
  • weight is hanging instead of stacked
  • the force vector is inefficient

A move feels light when:

  • the CoM is low and close to the wall
  • the feet carry more horizontal load
  • the CoM sits within a stable friction zone
  • the body forms a mechanically efficient triangle

“Light climbing” is simply correct CoM placement reducing required force.

5. Micro-Shifts of the CoM Change Everything

Small adjustments of 2–8 cm in hips, knees, shoulders or ribs can:

  • halve the required pulling force
  • turn a bad sloper into a good one
  • stabilize a deadpoint
  • eliminate swing
  • allow static movement where dynamic seemed necessary

Elite climbers are constantly micro-positioning their CoM.
It looks effortless because the adjustments are small but perfectly timed.

6. Balance = CoM Position, Not Stability Feeling

Balance (“feeling stable”) is subjective.
CoM position is objective.

You are balanced when the CoM is:

  • over the feet
  • aligned with the primary force vector
  • inside the geometric support zone

Dropknees, twists, flags and hip drives all exist for one reason:
they relocate the CoM into a zone where holds become usable.

Good climbers do not rely on the feeling of balance.
They rely on the geometry of balance.

7. The Fundamental Rule: Move the CoM First

Almost every technical mistake comes from violating this rule:

The CoM must shift before the limb moves.

Correct sequence:

  • shift CoM into the usable zone
  • establish stability
  • align the force vector
  • then reach, pull or step

Errors happen when:

  • arms move while the CoM is still unloaded
  • feet step without a CoM solution
  • dynamic moves start with the CoM in the wrong place
  • climbers try to hold a hand position with poor vector alignment

Elite movement is simply CoM-first movement.

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