This blag has moved to the new address.
Originally from AquaVolo.com
I’ve been meaning to write a post about the use of the pull buoy in training for quite some time now but, unfortunately, never got around to it until today. What finally made me sit down and write this post was the swimmingscience.net article titled “7 Theoretical Reasons to Use a Pull Buoy.” It’s an interesting read and I highly recommend it. As the title implies, the article outlines reasons to use a pull buoy. I, on the other hand, would like to talk about one reason NOT to use a pull buoy. I believe my argument against the use of pull buoy outweighs most of the arguments for it.
For reasons that will become apparent later, I’ll first quickly explain the paramount importance of the core in swimming.
We can think of a human body as a set of interlinked components that work in unity. It’s helpful to visualize this set as a chain where each link represents a different body part as in the diagram below. This chain is called the kinetic chain.
(Image source: Complete Conditioning for Swimming. Dave Salo and Scott A. Riewald (2008))
To swim fast and efficiently, all links in the kinetic chain must work in coordination. Because all links in the chain are connected, a change in one link impacts the entire chain. When one link breaks, so does the coordination between the links. We call the link that orchestrates the coordination of various parts of the body the core. The core achieves this coordination by performing several important tasks—transfer of power, base of support, stability, link between arms and legs, and balance—that are illustrated in the following image and explained in greater detail below.
Transfer of power
Chains are often used to transfer power. A bicycle chain, for example, enables the transfer of power from the pedals to the wheels. In swimming, the core transfers power between the legs and the torso and the arms.
When a link in the chain breaks, the transfer of power is impeded. When the core fails to transfer power between the lower and the upper parts of the body, the swimmer is left with power produced by smaller muscles (e.g. shoulders). This not only reduces total available power, efficiency and speed, it also increases the risk of injury.
Base of support
Swimmers, unlike land-based athletes, must create their own base of support to generate propulsive movement. Runners, for example, use ground as the base of support that they can push off from. Swimmers, however, train in a fluid environment and don’t have a solid surface to use as the base of support. What swimmers use instead is the core. The stronger the base of support, the more propulsive power the swimmer can generate.
When the core fails to provide stable base of support, swimmer’s efficiency and speed drop. Frequently you can see a swimmer who is working very hard with his legs and arms yet moving forward very slowly. It looks as if he’s spinning in one place. This happens because the core doesn’t provide the stable base of support and the swimmer has nothing to push off from.
Link between the arms and the legs, balance and stability
Fast and efficient swimming requires coordinated movement of the body. The core achieves this coordination by linking the upper and the lower parts of the body and by providing balance and stability. When the core fails to perform these tasks, coordinated movement of the body breaks down and efficiency and speed drop.
Let’s look at one example. An outward hand sweep during the initial phase of the pull is a common flaw in freestyle swimming. What causes this flaw, many people believe, is late breathing. Late breathing might indeed be the cause, but the root of the problem is a lack of balance and stability.
When the core fails to provide balance and stability, the body is forced to find an alternative way to accomplish these tasks. Late breathing and outward hand sweep are the two side affects of the body’s alternative way to provide balance and stability. The outward hand sweep is a clear indicator that the core is failing to perform these two essential tasks.
Putting it all together
The core is the foundation upon which everything else is built. When the core is properly trained to perform the tasks discussed above, the swimmer has a strong foundation and potential to become fast and efficient.
Back to the pull buoy
Now that we understand the importance of the core in fast and efficient swimming, let’s look at what happens when you introduce a pull buoy.
When a swimmer puts a pull buoy between his legs, he essentially removes the core link from the kinetic chain (see the kinetic chain image above). As we have already established, when a link in a kinetic chain breaks, the entire chain is compromised.
The pull buoy provides artificial support and in essence relieves the core of its duties. The core no longer needs to provide a base of support, stability, balance, transfer of power or the link between the arms and the legs. All these tasks are outsourced to an artificial device: a pull buoy. The core can just sit back and relax.
Hopefully, it is clear by now why I believe that the pull buoy should not be used in training or at least their use should be minimized. While there are situations in which a pull buoy might be beneficial (such as drills, for instance), traditional use of a pull buoy for pulling is detrimental to a swimmer’s improvement. The pull buoy compromises the kinetic chain and robs the swimmer of an opportunity to train the core to perform the essential tasks that are necessary for fast and efficient swimming.
Originally from AquaVolo.com
The two images above represent two tools for two very different sports. The image on the left, DragSox®, is a power training tool for swimmers. The image on the right is a suit for the 2014 Olympics speed skaters. The purpose of these tools is diametric—DragSox are designed to slow the swimmer down while the speedskating suit is supposed to make the skater go faster. What they have in common is that they both use mesh. DragSox are entirely made out of mesh; the speedskating suit has a strip of mesh on the back for a “cooling effect.”
In order for us to understand the similarities between DragSox and the speedskating suit depicted on the image above, we have to quickly refresh our memory of fluid dynamics. (Please bare with me, it’s only three sentences!)
Fluid dynamics is an area of physics that studies how fluids behave when they are in motion. Both liquids and gases are considered fluids. The laws that apply to fluids apply to both, liquids and gases.
Now, let’s look at what happens when DragSox are used in the water:
One reason DragSox are so effective at creating drag in the water is due to the properties of mesh. As the swimmer moves through the water, mesh greatly disturbs the laminar movement of water, causes turbulence, and creates an area of low pressure directly behind the swimmer. This area of low pressure essentially sucks the swimmer backward. To overcome this suction, the swimmer has to exert more energy, which is the intended purpose of DragSox.
Since we already know that the physical laws that apply to liquids also apply to gases, we can predict that what happens to the moving swimmer with DragSox in the water will happen to the moving skater with a mesh suit in the air—the mesh on the back of the suit will disturb the laminar movement of air, cause turbulence, and create an area of low pressure which will create drag. In fact, this is exactly what happened during the last winter Olympics in Sochi: “it seemed that the vents on rear of the suit, put in to allow heat to escape, actually allow air to enter – in turn creating drag.” (1)
There were probably other reasons that would explain the slow times of the US Speedskaters in Sochi, but having a mesh strip on the back of the speed suit definitely contributed. All the designers needed was a quick review of fluid dynamics and this could have been prevented. Maybe now they can recycle those speedy speedskating suits and use them for drag-creating training tools!
Originally from AquaVolo.com
USA Swimming recently posted a short article titled “The Key to Freestyle Balance: Breathing and Kick”  in which the author, Matt Barbini, suggests that a lack of balance is the root of most common flaws in freestyle. The author finds that the key to balance is a “strong steady kick” and early breathing. While I agree that lack of balance is the root of most common flaws and that inconsistent kick and late breathing can throw off your balance, a strong, steady kick and early breathing alone will not make you a balanced and efficient swimmer. A strong and stable core is the foundation upon which everything else is built.
To maintain balance in the water the swimmer must have a strong and stable core. The core links the arms and the legs together and orchestrates the coordination between different parts of the body. If the core is weak, a stronger, steadier kick will not improve balance or efficiency significantly because the body cannot maintain balance. Salo and Riewal had a good analogy—a strong kick with an unstable core is like trying to push cooked spaghetti across the table. “It’s very difficult to push the wet noodle because of it’s floppiness. This is like trying to use your kick to push you across the pool when you have poor core stability”.  A strong, steady kick in isolation will not improve balance; you need a strong and stable core to attain balance and efficiency.
Late breathing is one of the most common flaws in swimming. As Barbini points out, it “causes a delay in returning to a clean body-line and necessitates a corrective motion – like an outward hand sweep”. Learning how to breath early will eliminate these problems. However, it’s the balance attained by strong and stable core that makes the early breath possible, not vice versa. Just like with kicking, an early breath with a weak unstable core will not improve balance.
Barbini’s article makes a lot of sense, pointing out that a lack of balance can lead to many problems. However, the most fundamental aspect of balance is a strong core. While flawed technique such as an inconsistent kick or late breathing can throw off your balance, strong and stable core is what allows you to attain balance and achieve the correct technique.
 Complete Conditioning for Swimming. Dave Salo and Scott A. Riewald (2008)
For swimmers… The difference between DragSox® and running shoes.
[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)