How does a swimmer propel him or herself through the water? How can a swimmer become a more proficient and faster swimmer? If you are asking these questions and want a better understanding of the fundamentals of swimming strokes, this article is written for you. We will attempt to explain the 2 ideas that make up most of swim propulsion and directly relate to a swimmer being able to perform efficiently and with the least amount of effort in the pool.
This brings us to the first fundamental concept which is known as "drag." Drag is the resistance a fluid expels when being forced to move or when someone pushes their hand from side to side in a submerged body of water. Basically, material things resist change to their velocity. The resistance a swimmer feels is discussed as a feeling of drag which slows any forward progress.
The "form drag" is the type that most commonly affects a swimmers' technique. The greater the size of the object moving through fluid, the more surface area, meaning more resistance or "drag" than a smaller object with less surface area. There are a few things swimmers practice to make their "form" as low profile as possible to minimize drag. The most widely used practice used by competitive swimmers is to streamline off all walls prior to beginning the stroke of choice. A streamline position is done by extending both arms above the head with no bend in the elbow. The hands will also be placed one on top of the other with fingers pointed straight and forward, palms facing the bottom of the pool. This in effect resembles an arrow with all parts of the body in one straight or "streamline" fashion which creates minimal drag.
In this photo you will see an example of a streamline body position which is used
by a swimmer when they push off a wall to begin lap swimming.
In order to fully understand how drag works, we need to discuss Newtown's Third Law of Motion which states, "For every action there is an equal and opposite reaction." In layman's terms, when a swimmer pushes back against the waters resistance, in return, the swimmer is able to move forward. Depending on the context, the term "drag" has different meanings in swimming. Is used to describe forces that impede forward motion as well as forces that are a launching pad for forward motion.
The second fundamental concept of swimming propulsion is called "lift." The best example to understand lift is to think about birds flying. Birds are able to get off the ground and fly because of the lift force. The 2 Required conditions for Lift are: #1. The angle of the wings and #2. The pressure imbalance between the bottom and top of the wings. The pressure below the wing must be higher than the air pressure above the wing.
Now that we have a visual on the prerequisites for lift, we can discuss the lift force itself. Once a bird begins to flap its' wings, pressure below the wings allow the bird to lift off of the ground and pitching its' wings at various angles allows the bird to either climb an altitude or lower itself back to the ground.
How do these lift forces relate to human swimming? Swimming creates lift just as a birds' wings do, however this lift propels the swimmer forward, rather than up. Although the term lift implies an upward motion, the force can influence an object in any direction. A swimmers' hand and arm is in comparison to that of the wings of a bird when discussing lift.
The best way to fully grasp and feel the lift in a swim stroke is by practicing a drill called "sculling." Sculling is designed to teach a swimmer to feel the sensation of propelling forward in the water solely from the lift force. In the sculling drill, the swimmers' hands/arms remain vertical as the swimmer sweeps the limbs out and away from each other and then changes the hand/arm pitch to sweep them in towards each other.
In this photo, you will see a swimmer practicing the drill
referred to as "sculling."
We hope this article helps you understand the 2 most basic and fundamental concepts in the sport of swimming. You can learn how to minimize drag and emphasize lift which will in turn help you with your distance per stroke swimming with less energy loss. If you are searching for a private swim coach and would like to hire our Team, let us know by either completing our contact page or swim lessons registration page.
This article is brought to you by: The Swimming Swan