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Butterfly Mirror Drill

The image below shows the optimal, underwater arm motion for butterfly. The black lines show the path of the hands. To replicate this motion, stand in front of a mirror with the arms straight and directly above the shoulders. Then perform the 7 steps listed. Move the arms very slowly at first, watching the arms in the mirror. Practice at a slow speed until you’ve mastered the motion. Then, slightly increase the speed of the arms and again practice until mastered. Keep practicing with small increases in the speed of the arms until they are moving at normal swimming speed.

  1. To begin the pull phase, flex the elbows.
  2. Watch the hands move slightly apart but keep them inside the elbows.
  3. Keep flexing the elbows until the hands are in the same plane with the shoulders.
  4. To begin the push phase, push the hands toward the legs.
  5. Extend the wrists as the arms straighten so the palms face down.
  6. As the elbows lock, touch the front of the thighs with the thumbs.
  7. Move the palms along the sides of the legs and then recover the arms to the starting position.

While it may feel natural to begin the arm motion by moving the hands to the sides, this puts the arms in a weak position. To increase the strength of the arm position, begin the arm motion with elbow flexion.

The butterfly hand path has often been described as a “keyhole,” and consequently, sideways motion is usually exaggerated. The hand path in the image is better described as “a very narrow keyhole.”

By |2020-04-08T17:34:17+00:00April 8th, 2020|blog|Comments Off on Butterfly Mirror Drill

Transform your swimming technique with these 3 science-based concepts

Every swimmer wants to swim faster. (No surprise there!) But you may not know that EVERY swimmer – from beginner to Olympian – can improve their swimming by understanding three basic swimming principles based on science and using cues to help remember and follow them.
The three principles (presented in non-scientific language) and a few examples of the cues that can help you remember and use them to swim faster are explained below.

1. The shortest distance between two points is a straight line.1

Although swimming from one end of the pool to the other may actually be a straight line, it is still easy to grasp this concept. Undulation (the up and down motion of a swimmer’s head, body, and legs) increases the distance the swimmer is traveling from point to point. ANY vertical motion has an effect on a swimmer’s velocity. All of that excess motion not only slows velocity and but also increases the resistance (drag) of the water. In turn, this increased resistance requires more force to overcome. Effective (faster) technique requires a swimmer to minimize vertical motion of the head, body and legs in all four competitive strokes. This is especially obvious in breast and butterfly stroke.

One suggested cue that can help a swimmer minimize vertical movement in butterfly is to keep the water level at the top of head during a non-breathing stroke cycle.

 

2. A smaller surface area creates less resistance (drag) than a larger area.2

Many of us have had the experience of streamlining our bodies to ski or bike faster. It makes sense to reduce the surface area of any shape to reduce resistance against it. Obviously, a streamlined body would look and function more like a fish than a block! (Imagine pushing your hand parallel through water versus perpendicular to the flow.) Yet swimmers of all ability levels have not yet mastered an effective streamline – the most basic component of good technique and the foundation skill for fast swimming. To swim fast, you must reduce the surface area of your body as much as possible and maintain that position for as long and as often as appropriate.

A sample of cues for an optimal streamline position includes:

  1. The visual cue is to see the bottom of the pool directly beneath the head.
  2. The kinesthetic cues are to feel:
  • one hand on top of the other
  • fingertips pointing horizontally at the pool wall
  • elbows locked
  • upper arms squeezing the ears
  • back arched
  • legs straight
  • feet together
  • toes pointed

Streamline position minimizes drag

Streamline front view

 

3. Continuous propulsion requires continuous force.3

This concept can be illustrated in swimming using the term Index of Coordination or IdC. A negative IdC describes a freestyle technique in which the beginning of the pull in freestyle is delayed until the opposing arm is fully extended. This causes gaps in propulsion and negatively impacts velocity. Commonly referred to as “catch-up” stroke, this delay is less visible at race pace but will always have a negative impact on a swimmer’s time. When the IdC is positive, a freestyler begins the pull before the opposing arm completes the push. This causes an overlap of propulsive force. Effectively mastering a positive IdC may well have the single greatest effect on a swimmer’s times and has the potential to significantly drop swim times. Before trying to swim with a positive IdC, a swimmer must master a zero IdC and can transition to a positive IdC with an increase in stroke rate.

A sample of cues to help achieve a zero IdC includes:

Enter the arm with a downward angle so that at the completion of the entry the hand is below the shoulder.

  • As the arm enters the water, angle downward so that the hand is the deepest part of the arm when the arm straightens.
  • At the finish of the push phase, straighten the arm with the hand beneath the leg.
  • See the entry arm straighten and feel the push arm straighten simultaneously.

The best thing about these three principles and corresponding cues is that the science behind each is so “eyeball obvious!”  It is impossible to dispute a law of physics, but it is equally difficult to dismiss what you can see with your own eyes or measure using simple tools (like video cameras, stop watches or lap counters).

Don’t take my word for it. Get in the pool and give these cues a try.

 

To summarize:

  • The shortest distance from one end of the pool to the other IS a straight line. ( 1Archimedes first articulated that the shortest path between two points in a plane is a straight line.)
  • A streamlined body creates less drag. ( 2Drag depends on the properties of the fluid and on the size, shape, and speed of the object.)
  • Catch-up stroke causes gaps in propulsion. ( 3A continuous source of propulsion produces the fastest swimming for the least cost in energy.)
By |2020-02-28T16:20:34+00:00February 28th, 2020|blog|Comments Off on Transform your swimming technique with these 3 science-based concepts

What does the index of coordination (IdC) have to do with swimming faster?

The IdC is a measure of arm coordination in freestyle. Specifically, the IdC indicates if the arm coordination is less effective by producing gaps in propulsion or if the arm coordination is more effective by producing a more consistent source of propulsion. The main benefit of more continuous propulsion is faster swimming.

An effective freestyle with “no gaps in propulsion” has been supported by research since at least 1955 (Counsilman). Since then, numerous other studies concluded that gaps in propulsion were counterproductive and should, in fact, be considered a technique error (e.g., Chollet, Millet, Lerda, Hue, & Chatard, 2003; Schnitzler, Ernwein, Seifert, & Chollet, 2006; Seifert, Boulesteix, & Chollet, 2003).

The IdC was developed in 2000 to quantify the relative position of the arms throughout the stroke cycle, (Chollet, Chalies, & Chatard). A zero IdC occurs when one hand begins to pull at the same time that the opposite hand completes the push (middle image). With a zero IdC, the arms are in opposition throughout the stroke cycle.

Index of Arm Coordination

A negative IdC occurs when the entry arm does not begin to pull when the opposite arm completes the push (top image). The failure of the entry arm to begin to pull causes gaps in propulsion. A negative IdC is also called catch-up stroke.

A positive IdC occurs when the entry arm begins to pull before the opposite arm completes the push (bottom image). A positive IdC is also called superposition, as there is an overlap in arm propulsion for a more continuous source of propulsion.

The science overwhelming supports a positive IdC for the fastest swimming. Yet, swimmers are almost always using a negative IdC, often -5% to -10% and even lower. A swimmer cannot maximize velocity with a negative IdC.

Swimmers usually only use a positive IdC at velocities above 1.8 m/sec. Even at the fastest swimming velocities (over 2.0 m/sec), an IdC above 5% is rare. An IdC over 10% and probably over 20%, however, is possible and also essential for the fastest human swimming.

Unfortunately, typical training promotes a negative IdC. Swimming longer distances at a slower stroke rate, fatigue, and an arm entry parallel to the water surface all encourage a delay in beginning propulsion with the entry arm. The result is that swimmers are usually practicing an arm coordination that is counterproductive to swimming fast.

Fortunately, there are strategies that can help a swimmer learn to swim with a positive IdC and make use of the arm coordination that produces the fastest swimming. Optimizing the IdC requires 1.) mastering an effective downward angle on the arm entry, 2.) maintaining primarily backward hand motion as the torso rotates upward on the push phase, and 3.) gradually increasing the speed of the arm recovery with an increasing stroke rate. Any swimmers who hope to optimize performance would do well to evaluate their own IdC and work to improve it.


Interested in IdC? Follow the links below to learn more!

https://www.youtube.com/watch?v=DYn51lJxO6U

https://www.iat.uni-leipzig.de/datenbanken/iks/bms/Record/4019193

https://www.iat.uni-leipzig.de/datenbanken/iks/bms/Record/4032674

By |2020-01-22T20:11:06+00:00September 23rd, 2019|blog|1 Comment

Can Less Mean More?

How Triathletes Can Get the Most Out of Limited Time in the Water

We get it: There is a limited amount of time that a triathlete can spend training in any one sport. It doesn’t help that swimming is most likely not a triathlete’s favorite event – or that access to water for training might be a significant impediment to training year-round.  So how can you make your swimming more effective and improve your finish times – without increasing swim training times?

For starters, science doesn’t push for ever more time/distance in the water as the best way to improve your swim times. In fact, just the opposite is true: research suggests that even a limited time in the water can produce a substantial improvement in performance time. Obviously, no one is advocating that swim training isn’t required to be successful. Instead, this post – and the significant research behind it – suggests 5 ways you can make the most out of every swim.

  1. Dedicate a large portion of your time in the water to swimming slow. This allows you to avoid fatigue and focus more on technique.  Your goal is to establish a regular routine of short, slow swims with the priority on skill improvement.  (Your endurance training with your biking and running make this focus on technique swimming possible.)
  2. Practice breathing less frequently to improve visual input. When swimming slower, a swimmer can minimize the number of breathing strokes. If the head is motionless on nonbreathing strokes, swimmers can better focus on visual input. They will be more certain of what they see and be better able to control their movements using visual feedback. This will also help when you are swimming in open water when conditions are less than ideal.
  3. Set a goal and work towards improving technique on every swim. Strokes performed with an ineffective technique (because of fatigue, speed, breathing, etc.), are not likely to improve or reinforce effective technique. It is essential to practice your technique to develop skills that enable you to swim faster. It’s far better to swim more slowly while focusing on technique elements like arm entry, head position, pulling through to the thigh on each stroke, etc., than it is to swim as fast as possible for as long as possible.
  4. When possible, practice in race-specific conditions. The ultimate goal of skill-learning is to maintain the most effective technique throughout an entire race. A reduced distance regimen allows more time for swimmers to practice under simulated race conditions (i.e. choppy water, swells, transitions). For example, training sets that include a start from shore provide swimmers with the opportunity to practice starts.
  5. Get feedback from a coach or fellow triathlete. While many triathletes work regularly with both sport and strength coaches, many do not. For both, asking for feedback on some aspect of your swimming technique can provide valuable information. For example: Is your head level when not breathing? Do you raise your elbows the same way on left/right hand strokes? Are you “dragging” your legs or is your body position basically level? Are you rolling your body excessively when you begin your stroke? This kind of feedback is essential to improving technique. If you are fortunate enough to have a swim coach, don’t be shy about asking for a regular short technique assessment. Getting a friend to video record your stroke for you to see can also be an eyeopener.

The bottom line: A limited amount of time spent swimming results in fewer stroke cycles and allows a triathlete to focus on technique in a way that enables lasting change.  Fewer cycles also mean less shoulder stress and pain. Shoulders that are not stressed and not suffering from inflammation are not as likely to interfere with swimming, biking or running. Which means: you can get the most out of your practice swims, swim faster with better technique, and devote more time to the rest of your packed schedule.

By |2020-01-22T20:11:08+00:00June 21st, 2019|blog|Comments Off on Can Less Mean More?
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