Hockey requires more athletic ability than many other sports because it's played on ice.

Hockey is very unique compared to other sports.

This is because the game is played on ice and the players move on skates with a thin blade on a surface that has very little friction. Playing a sport on ice while wearing skates requires an exceptional degree of coordination and athletic ability. Hockey requires perhaps more athletic ability than many other sports with the exception of other sports played on ice.

Because of the ice, physics plays an important role in hockey, and specifically skating. There is a low coefficient of friction of ice therefore, hockey players cannot move with “normal” movement patterns as other athletes who play on wood, grass, sport court, acrylic-topped hard court, etc. Because of the physics of moving on ice, hockey coaches and skating coaches must have a clear understanding of the unique movement patterns of hockey players in order to improve their skating performance.

The laws of physics

Sir Isaac Newton in 1687 wrote his first book on the laws of physics (or motion): Mathematical Principles of Natural Philosophy. In the book, Newton published his laws of movements that hold true to this day and are applicable to hockey skating:

Inertia

A body at rest, or moving in a straight line, will remain at rest or moving in a straight line unless it is acted upon by a force. An example of this is that a player who’s gliding on two skates will remain in motion until the friction of the ice slows him/her down, another player causes him/her to turn which will slow the player, and/or a player at a face-off will not move until he/she breaks inertia by pushing off to chase the puck.

Force = mass x acceleration

The speed of a player is equal to the player’s mass (body weight) and the muscle power to produce force to move the body. The speed of a player equals the force applied. The more force a player produces the faster he/she will be. This law of motion applies to getting our players to push as hard as they can when accelerating or skating at full speed, and it applies to our players doing the correct exercises when they are training. We want our players to have a high level of muscle power in order to be faster and quicker.

Equal and opposite action/reaction

This law states that for every action, there is an equal and opposite reaction. This is important in skating because in order for a player to move on the ice, he/she must push to the side with the skates. When the legs push to the side (hip abduction), the arms must move in an equal and opposite reaction. An example would be when a player is skating straight, his/her left leg pushes to the side, and both arms must react by moving to the right.

Physics of ice

Ice has a low coefficient of friction, which makes it slippery. It also causes hockey players to propel themselves down the ice by pushing to the side.

A player skates forward by pushing off with a force perpendicular to the other skate blade which is either gliding or in the recovery phase, and not yet on the ice. Since the friction of the skate blade on the ice is almost zero, this is the only way a player can move forward. The same principle applies to skating backward and forward and backward crossover turns.

Unique movements of skating because of physics

Acceleration

The first two or three acceleration strides from a stationary position are usually the only time a player will push straight backward.

Striding straight down the ice

When a player is skating straight, he/she will push to the side with the legs (hip abduction), and the arms will move in an equal and opposite reaction, moving side-to-side. Remember, you “can’t break the law” (the laws of physics) therefore we must understand the concept of action-reaction and teach our players proper arm and leg movement. When a player moves this way, he/she will be faster, have better balance, and maintain momentum.

Turning

When performing a gliding turn, most of the weight has to be on the outside skate (inside edge) because of centrifugal and centripetal forces.

Centrifugal force is the action pulling a player out of the turn, same as when making a high-speed turn in a car and the force pushes the driver sideways in his/her seat. It is for this reason players lean into a gliding turn, so as to counteract the centrifugal force that wants to pull the player out of the turn. Centripetal force is the action necessary to keep a player moving in the turn by using the skate edges to counteract being pulled out of the turn.