Enter the weight being held, the distance from the elbow to the hand, and the distance from the elbow to halfway up the bicep to determine the muscle force.

## Muscle Force Formula

The following equation is used to calculate the Muscle Force.

MF = m*g*D1 / D2
• Where MF is the muscle force (N)
• m is the mass of the weight being lifted by the hand (kg)
• g is the acceleration due to gravity (m/s^2)
• D1 is the distance from the elbow to the hand
• D2 is the distance from the elbow to the center of the bicep

This formula is only an estimation and only holds when the forearm is parallel to the floor.

## What is a Muscle Force?

Definition:

Muscle forces commonly refer to the magnitude of the force exerted by a muscle, or group of muscles. Muscle forces are measured in units of Newtons (N). One Newton is equal to the amount of force required to accelerate one kilogram of mass at a rate of one meter per second squared (1 kg*m/s2).

## How to Calculate Muscle Force?

Example Problem:

The following example outlines the steps and information needed to calculate Muscle Force.

First, determine the mass of the weight. In this example, the mass of the weight is 50 kg.

Next, determine the length from the elbow to center of the hand. For this problem, the length is 10 inches.

Next, determine the length from the elbow to the center of the bicep. In this case, that length is 4 inches.

Finally, calculate the muscle force using the formula above:

MF = m*g*D1 / D2

MF = 50*9.81*10 / 4

MF = 1,226.25 N