Monday, October 11, 2010

FORCING Your Way Down The Pool? Reduce Drag By Improving Swimming Stroke Technique

With the conclusion of the Commonwealth Games in India, many of the top level swimming meets have concluded, and most of the world’s top swimmers have put in their best swims of the season. It is clear that for the most part, swimming performances this year obviously in general have been slower. Many reports, blogs, and swimming discussion forums during the Summer of 2010 are full of statistics by event, stroke, and age.

It would seem that at least in the near future the quickest path back to the performance times attained using the high tech swimsuits would be strategies aimed at reducing the effects of drag. No matter what your opinion of how high tech swimsuits attained the performance results that shattered the swimming record books at almost any level, there is probably little disagreement that the performance results were attained by the reduction of drag. Obviously, reducing swimming drag not only allows a swimmer to go faster, but swimming science has objectively shown for years, it can also reduce the energy cost of swimming. Just like in motor sports, methods of reducing drag allow the car to go faster, even though the horsepower of the car remains unchanged.

Nevertheless, to my surprise all through the Summer of 2010 on many blog and discussion forums was more dialog and great debate about how to increase propulsive FORCE to improve swimming performance. There were numerous posts about this term called “EVF” an arm position believed to generate better propulsive force in freestyle swimming, and videos of swimmers proclaiming that now in order to get faster they needed to somehow work even harder to get back to those tech suit times.

But what about working harder in the right direction?

So why did all the dialog about FORCING our way down the pool continue? For decades in swimming, we tried to reduce the area of fabric in swimming suits, or made them so paper thin you could see right through them. Now we find that more fabric covering the body is actually better at lowering the drag. Tech suits did not improve propulsive FORCE or power or even allow us to swim “down hill.” This technology put us right on top of the water and probably higher than ever before. For decades in swimming, the best have been emphasizing that increasing the power or the FORCE in swimming is the pathway to success. But in the blink of an eye, the suit did not change stroke technique, improve fitness, or make anyone stronger or more powerful. It was a passive device that went along for the ride. The tech suits simply reduced the drag by most accounts from 2 to 3 percent. Even in the face of the biggest short-term performance improvements in swimming history, I was continually surprised to read the same basic dialog and debate about increasing the FORCE or power as the main pathway to improved performance.

Just as new technology changed the configuration of swimsuits, a similar configuration change can be made that will improve swimming technique. Velocity Meter/Video Telemetry was used in the early development and measurement of high tech swimwear that dates back to the mid 1990’s. Today, it can be incorporated in the same manner to identify the drag characteristics in swimming technique. Being able to objectively observe that the instantaneous changes in velocity during one stroke cycle that can fluctuate sometimes 30 to 40 percent (see above) provides swimmers and coaches a clear picture for making more informed decisions. Specific phases of the stroke cycle once identified can easily be transferred everyday at practice to objectively design training strategies aimed at the weaknesses in our swimming technique. Just having the knowledge of exactly where the drag phases occur during a stroke cycle without guessing is a first important step. This technology presents a microscopic view of swimming technique because the measurement process collects velocity telemetry at 1,000 data points a second that is significantly higher than the human eye is capable of sensing.

Therefore, if you feel like you are continually trying to FORCE your way down the pool, you might consider working with the individuals that developed the methodology used in reducing the drag in tech suits, and begin working on reducing the drag in your swimming technique. Not only can you go to the pool with a new swimsuit, but a new swimming stroke as well! We helped swimming suit companies using this technology achieve optimal results by reducing the drag, so why not accomplish the same goal by reducing the drag in your swimming technique?

It is a simple plan that stars with working harder in the right direction!

Budd - TeamTermin Sports Performance

Thursday, April 29, 2010

Fishing Around For Better Swimming Technique Analysis?

Unfortunately, there appears to be more longitudinal research data available regarding the swimming proficiencies of various fish species than long term data following large numbers of randomized human swimmers.” This is a quote from a January blog post on The Athlete Village web site titled “Improved Swimming Performance Utilizing Video Analysis” by Coach Abigail. Having been involved in swimming for many years, and especially in swimming research, unfortunately, this is one of the most insightful statements about the sport of swimming you will find on any web site. Because until very recently, the ease of capturing digital video into a computer, and the advent of video web sites, where this medium could be shared to the masses, was not an easy task. Until recently, swimming stroke technique analysis has always been a bit of an art form. It was reserved for those that seemed to possess a special insightful visual power of observation, driven by a unique vocabulary of terms and catch phrases that almost made it mystical in nature. While we mere mortals often deferred to these people for information, these soothsayers still exist in our sport, using that same belief system and are now imparting their beliefs all over the internet.

In keeping with Coach Abigail’s statement about fish research, it made me think, that every now and then, even I get a new rod and reel, and change the line, but does it mean that I will catch more fish? And so all over the web, many have jumped on the underwater video analysis band wagon or the DVD of the latest greatest swimmer is now on sale. Swimming traditionally has always been a bit of a copy cat sport, that many have capitalized on, but unfortunately whether your looking from the surface or underwater, it’s still virtually the same basic belief system being used that has surrounded stroke technique assessment. Using subjective terms, do all those basic analogies we always hear, actually happen when we swim through the water? Can someone actually just visualize the phases of the swimming stroke that really generate the most propulsive force, and at that moment, know exactly how fast I am really going? Can even a swimmer in the water actually “feel” when maximum velocity is achieved during a stroke cycle? Well, for the most part, you probably can by recycling that same belief system and applying it with underwater video. That’s because up until now, objectively measuring swimming proficiency or technique was really hard to do, took a lot of work, and typically required a laboratory environment.

Freestyle Velocity Meter/Video Telemetry from TeamTermin Sports Performance on Vimeo.

So, with all that said, how about checking out my new rod and reel! It’s called Velocity Meter/Video Telemetry, and is a cross between underwater digital video, combined with high speed velocity telemetry. We refer to it as “Hybrid Video”, because it captures underwater digital video that streams directly into the computer, and at the same time, high speed instantaneous velocity telemetry also streams into the computer, where both signals are synchronized into one file for immediate playback. When I play back the file, I can see exactly where and in what phase of the stroke cycle create propulsive velocity, and the phases that don't produce anything. Front, back or somewhere in between and by the way, after almost 20 years of collecting this type of telemetry, every swimmer is really different. It takes 1000 data points of velocity telemetry a second, to actually reveal the very subtle velocity excursions positive or negative, during one stroke cycle. And with fluctuations in velocity of more than 40 per cent, sometimes in less than three tenths of a second, really makes me wonder if that belief system with just regular vision, above or below the surface, can really sense all this variance in velocity. Best of all, it is also very portable, and has been gaining popularity on many pool decks, around the world, so no need for that laboratory anymore!

Is your swimming technique ready for a new rod and reel? If so, the only thing we promise, is that you will never look at your swimming, quite the same way ever again!

Sunday, January 3, 2010

Changing the Face of Swimming Technique Analysis – Part II - Stroke Frequency/Velocity Graphs

In the last blog, “Changing The Face of Swimming Technique Analysis – Velocity Meter/Video Telemetry”, I described technology now available that gives a swimmer or coach an instantaneous true view of the accelerations and decelerations of the swimming stroke. The most important feature of this technology is the instantaneous feedback swimmers and coaches receive, since everything is collected and can be replayed in real time right at poolside. After a testing session, everyone can go to practice, knowing exactly where the drag or decelerations occur in every stroke cycle, and start to devise methods to optimize the pattern. No more subjective guesswork or “theories” that simple observation alone provides. However, there is another really beneficial tool from this testing, that provides coaches a technique tool that can be used everyday at practice, using a basic stopwatch.

The tool is called a “Stroke Frequency/Velocity Graph”, and can be output from the Velocity Meter/Video telemetry. The swimmer performs a series of trials starting with slow speeds, progressing to as fast as the swimmer can go. The data is graphed yielding the optimal relationship of swimming speed to stroke frequency/tempo for that swimmer. For you math majors, you will notice that the fit of data produced an r-squared value of .9955 which means statistically, this is a highly reliable relationship, and the individualized nature of the graph can not be understated. In the following, we will demonstrate the sensitivity of this graph, and a sampling of the practical application of its use.

The Stroke Graph below is freestyle collected a couple of months ago on a Master’s swimmer that holds several world records. This graph represents the stroke rate/tempo (x-axis - bottom) and swimming time for one lap of a 25 yard pool (y-axis - vertical) for this swimmer. The solid blue line with the solid blue dots represents the swimmers “regular stroke technique.”

In addition to the basic test, this swimmer wanted to experiment with different techniques to see what effect it might have on velocity, compared to the “regular stroke technique.” The legend on the right defines the changes in technique we tried. All of these individual trials were conducted at top speed, and some were repeated a number of times to ensure the techniques were properly executed. These trials are plotted individually using different colors, to demonstrate how they compared to the regular technique.

For coaches, this information is extremely powerful because once the “regular technique line” has been constructed, experimenting with different stroke techniques can now be objectively compared, using a basic stopwatch. In addition, daily training can be constructed to rehearse the optimal stroke rate/tempo and lap time desired for competition. Depending on the race distance and pace desired, the best stroke rate/tempo can be pre-determined. Data points that fall below the line represent technique that is not beneficial, while any data points at or above the line represent a potential beneficial change. The sensitivity to changes in stroke technique using this graph is clearly demonstrated, by how the individual changes in technique fared against the regular technique line.

In this swimmers case, the optimal frequency that yielded the best swimming time consistently fell between 50 and 60 strokes cycles per minute. Even though the individual data points visually do not look far from the line, it is important to understand that the frequency number represents that stroke technique between 50 to 60 times for every minute of swimming, so the cumulative effect of even small deficiencies is significant. This reinforces graphically how subtle changes in swimming technique can affect performance, either positively or negatively, but in any case, the experimental changes were objectively defined.

This description is really an overview of the potential benefits using these graphs in daily practice. This particular swimmer has written an insightful detailed analysis on his web site. I have included a link to the site for those interested in reading more in-depth on how this type of technology can be used to make objective decisions, that can equate into real performance gains without guessing.

As usual, should you have any questions or would like to learn more, you can always contact me through the website:

Looking forward to testing your technique soon…