Newton's First Law of Motion, often called the Law of Inertia, states that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.

Here's how it applies to the clean and jerk:

1. The Clean:

* Initial State: The barbell is at rest on the platform.

* Force Application: The lifter applies a force to the barbell, accelerating it upwards.

* Inertia: The barbell resists this change in motion due to its inertia. This is why it takes effort to lift the barbell.

* Maintaining Motion: Once the barbell is lifted, the lifter needs to continue applying force to keep it moving upwards and to their shoulders. This counteracts gravity, which is pulling the barbell back down.

2. The Jerk:

* Initial State: The barbell is at rest on the lifter's shoulders.

* Force Application: The lifter applies a powerful upward force, extending their legs and hips to accelerate the barbell upwards.

* Inertia: The barbell again resists this change in motion due to its inertia.

* Maintaining Motion: The lifter continues to apply force to keep the barbell moving upwards and to fully lock out their arms above their head.

In essence:

* Newton's First Law explains why the barbell resists being lifted in the first place.

* It also explains why the lifter must continually exert force to keep the barbell moving upwards throughout both phases of the lift.

* The cleaner and jerk are essentially exercises in overcoming inertia and applying force to change the state of motion of the barbell.