Newton's first law:

An object at rest will remain at rest - An object in motion continues in motion with the same speed and same direction unless by an unbalanced force.

In Swimming:

The swimmer will stay in motion, unless the water produces resistive force that requires propulsive forces for it to overcome.

Newton's 2nd law:

Acceleration is produced when a force acts on a mass and the greater the mass, the greater the amount of force needed to accelerate.

In Swimming:

The force produced by the swimmer is equal to the mass, multiplied by acceleration of the swimmer in the water.

Force Formula:

force = mass x acceleration.

Newton's 3rd Law:

For every force there is a reaction force that is equal in size, but opposite in direction. an object can push another object, making it get pushed back in the opposite direction equally.

For every action there is an equal and opposite re-action.

In Swimming:

Can relate to the standard hand/arm stroke, the hand travels downward in the water and then backwards to move the swimmer forward. Creating an equal and opposite reaction, the swimmer is kept afloat and moved forward.

Momentum Formula:

p = mv - p is momentum, m is mass in kg and v is velocity in m/s