[repost from AquaVolo]
The goal of every competitive swimmer is to swim faster. One way to swim faster is to reduce drag. One way to reduce drag is to improve your body position in the water by making it more horizontal and stable. A more horizontal body position displaces less water as you move forward. The less water is displaced, the less drag the swimmer has to overcome. What makes the body position horizontal, creates stability and reduces drag is balance. This balance is achieved by engaging core muscles and by pressing down the lungs. (Pressing down the lungs brings the hips and legs up, acting as a lever.) When one of these two components—engaging core or pressing down the lungs—is missing, the body position gets distorted, efficiency falls and speed drops.
I have mentioned in a previous post that when we learn a new movement, our brain generates new motor pathways that carry the signals from the brain to the body parts responsible for that movement. And that “the more a particular pathway is activated during consistent, purposeful action, the likelier it is to be stabilized [become automatic].”(1)
Let me summarize what I have just written:
1) one way to swim faster is to reduce drag;
2) swimming with a horizontal body position reduces drag;
3) balance is required for attaining a horizontal body position;
4) balance is achieved by engaging core muscles and pressing down the lungs; and
5) swimmers need consistent and purposeful training to make new movements automatic.
Based on these insights, we can assert that swimmers need to consistently and purposefully try to achieve balance by engaging the core muscles and by pushing down the lungs. We can also say the opposite, that swimmers need to minimize activities that distort horizontal body position and discourage engagement of core muscles. One activity that both distorts the horizontal body position and discourages the use of core muscles is kicking with a kick board.
The idea behind a kick board is to provide support for swimmers’ arms so they can concentrate on the kick. However, for many swimmers, especially younger swimmers and those with weak core and poor balance, kick board introduces serious drawbacks.
First, as the swimmer kicks, his hands press down on the kick board that is extended in front of him. In addition to adding pressure on the shoulders, pushing down on the kick board creates a lever that lifts up the lungs.
Similarly, when the lungs go up, hips and legs go down (it’s the same lever effect).
As we have already established, to have a horizontal body position the swimmer has to push down with the lungs which aids in elevating the hips and legs. The exact opposite happens when you kick with a kick board: the lungs go up and the legs go down.
Some might argue that the swimmer doesn’t have to press down on the kick board, which is a valid argument. However, due the physical properties of a traditional kick board, which is very buoyant and not easily submerged, there will always be some pressure from the hands on the board. The arms of a perfectly streamlined swimmer reside slightly below the surface of the water. When the swimmer places his arms on the kick board, which is on the surface of the water and is not easily submerged, he is faced with two choices: to press down on the board to try to attain a horizontal body position (which causes the lever effect outlined above) or not to press down on the board and leave the arms at a slight angle (from shoulders up to the surface of the water). In either case, there will always be some distortion in the body position.
Second, many swimmers use the kick board as a stabilization platform. They grab on the kick board and use its high buoyancy property to balance their body in the water to achieve stability. Instead of using the core muscles to stabilize and balance the body, they use an external device. When swimmers do this, they are discouraging the use of the core muscles which are essential for developing a horizontal body position. Swimmers that use the kick board as a stabilization platform never get an opportunity to learn how to use their core to balance and how to develop an efficient body position.
After we created VB AIR and started training with them, we discovered a latent benefit that we had not anticipated: VB AIR are the perfect split kick board. VB AIR and kick boards are made from similar materials and both are buoyant. However, VB AIR are significantly less buoyant and easily submerged, which makes them so great for kicking.
First, although VB AIR do provide support for arms, they are not as buoyant as the kick board. The weight of relaxed arms will submerge VB AIR just below the surface of the water, which is ideal for streamlined body position. Swimmers cannot press down on the VB AIR, as they can with the kick board, because the VB AIR will sink and the swimmer will lose balance. Hence, the lungs will not be pushed up and the legs will not be pushed down because there is no lever effect as in the case with the kick board.
Second, unlike the kick board, VB AIR cannot be used as a stabilization platform because they do not provide enough buoyancy to support the weight of the body. As a result, swimmers must engage core muscles to balance themselves. If there is no external device to use as a stabilization platform, swimmers have no choice but learn how to use core muscles and lungs to balance themselves in the water.
To summarize, balance allows the swimmer to achieve a horizontal body position which reduces drag and results in increased speed. Balance is gained by engaging the core muscles and pushing down the lungs. As with any movement, to make the horizontal body position automatic swimmers need to consistently and purposefully practice by engaging the core and by pushing down the lungs. Activities that distort horizontal body position and discourage use of the core to attain balance, such as kicking with the kick board, need to be minimized. We believe that VB AIR are an effective alternative to traditional kick boards. Like the traditional kick board, VB AIR provides support for swimmers arms so that the swimmers can concentrate on the kick. Unlike the traditional kick board, VB AIR force the swimmers to use the core muscles and to push down the lungs to achieve balance in the water. Improved balance leads to improved body position which results in faster speed.
Introducing VB AIR
1. What’s Going On In There. Lise Eliot (2000)