## TORQUE | ## The three terms are synonymous |
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## "The word 'strength' ... actually represents torque [or moment]. All real-world performance (eg, sprinting, lifting weights, getting out of bed, writing) represents manifestations of torque by the musculoskeletal system" (Lieber & Bodine-Fowler, 1993, p. 852). |
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- A moment is a turning effect, produced by a force at some distance from an axis of rotation:
M=Fs #### Therefore, a moment's magnitude depends on:

- F, the force applied,
- measured in Newtons (N) or pounds (lb)
- depicted as a vector with a line of application

- s, the force's moment arm
- measured in centimeters (cm) or inches (in)
- the perpendicular distance FROM the force's line of application TO the axis of rotation

Accordingly, a moment is measured in units like Newton*meters (or Newton*centimeters) or inch*pounds.

We typically hyphenate these units; we use the * symbol here as a reminder that we derive these units as the product of two basic measurements.

- F, the force applied,
- Just as a FORCE produces straight line (linear) acceleration in an object at rest.
F=ma a MOMENT produces an

*angular*acceleration in an object (like a body part) around an axis of rotation (like a joint axis).M=Ir where I is the moment of inertia and r is the angular acceleration.

- ground reaction moments
- joint moments

Reference:

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