And The Most Efficient Swim Stoke Is…

June 21, 2012 7:35 am 0 comments

Share This:

Subscribe:

Author:

Tags:

Swimmers, I mean top level swimmers, have never agreed about which of two arm movements is most efficient for freestyle swimming. In one corner, we have proponents of the paddle stroke, also known as the deep catch stroke, for which the arm is extended and which pulls the water like a boat paddle. In the other, we have proponents of the propeller stroke, also known as the sculling stroke, for which the arm is bent at the elbow and makes a slight S-shaped curve as it moves through the water. Now, thanks to researchers at Johns Hopkins University, we have our final answer: the deep catch stroke is more effective and more efficient than the sculling stroke. Finding that answer wasn’t easy. A Johns Hopkins news release reports that scientists from the department of engineering used high-precision laser scans and underwater videos of elite swimmers, then turned to animation software to change the shape of the static arm in such a way as to match the video sequence. The team then ran computer simulations to study the flow of fluid around the arm and the forces that acted upon the limb. Each simulation involved about 4 million degrees of freedom and required thousands of hours of computer processing time. Study author Rajat Miittal says his research disproves the long-held conviction of many swim coaches that the sculling stroke delivers more speed. “Sculling, in my view, is a swimming stroke that is based on an incomplete understanding of fluid mechanics,” Mittal said. “We found that lift is indeed a major component in thrust production for both strokes, and that certainly indicates that the arm does not behave simply like a paddle. However, the simulations also indicate that exaggerated sculling motions, which are designed to enhance and exploit lift, actually reduce both the lift and drag contributions to thrust. So, lift is in fact important, but not in the way envisioned by these early coaches who were trying to bring fluid mechanics into swimming.” Got that? Read more from Johns Hopkins.

Leave a Reply


Recent Posts

  • Attitude Pain Computer Brain Games Are For Losers

    Computer Brain Games Are For Losers

    Brain games, the computer based mental challenges that promise to boost the brain power of older adults, are an excellent way to waste time, but they do almost nothing to make us smarter. That’s the opinion of 69 scholars, including many cognitive psychologists and neuroscientists from around the world. A Stanford University news release reports that the scholars, who have jointly issued a statement expressing their skepticism, say that while people who play computer brain games may improve their scores on […]

    Read more →
  • Pain Exercise Pain Predicts Broader Pain Threshold

    Exercise Pain Predicts Broader Pain Threshold

    How much you hurt after exercise is a good predictor of how much you hurt in life, according to research conducted at the Rutgers School of Dental Medicine, where they know a thing or two about pain. Researchers have known for years that exercise generally helps us tolerate pain. They even have a name for the phenomenon; it’s called “exercise-induced hypoanalgesia” or (EIH), but you knew that. Researchers have also known that some people respond better to the pain-diminishing influence of […]

    Read more →
  • Attitude Pain Worried About Ebola Yet?

    Worried About Ebola Yet?

    Are you worried about Ebola yet? At least one out of four American are, according to a new Harris Poll/HealthDay survey. And the most disturbing thing about the poll is that it was taken more than a week ago, before a nurse in Dallas who had treated an Ebola patient became sick, compelling the CDC to rethink the preparedness of U.S. medical workers to deal with the crisis. HealthDay reports that the online poll of more than 2,000 adults, taken between Oct. […]

    Read more →
  • Pain Repeat Knee Injuries:  What Are The Odds?

    Repeat Knee Injuries: What Are The Odds?

    Ever wonder what the odds are that you’ll re-injure a knee after an ACL repair? Now we know, and the answer is: it depends how old you are.  If you’re in high school, and if you are reading this you are probably not in high school, you’ve got a 17 percent chance of re-injury. That sounds scary until you read the full report from researchers at the University of North Carolina, which claims a 20 percent chance of injury on […]

    Read more →
  • Uncategorized Lifting Weights Improves Your Memory

    Lifting Weights Improves Your Memory

    Can’t remember how many reps you should do of squat thrusts? Do a few more reps and it might come back to you. Slowly. Researchers at Georgia Tech are persuaded that an intense workout of as little as 20 minutes can enhance episodic memory, also known as long-term memory for previous events, by about 10 percent. A Georgia Tech news release admits that the school isn’t the first to find that exercise can improve memory, but their study, which was […]

    Read more →
  • Pain Knee Pain? Forget About Acupuncture

    Knee Pain? Forget About Acupuncture

    Got a knee that won’t stop giving you pain? Don’t waste your time with acupuncture. According to researchers at the University of Melbourne in Australia, the therapy does little for knee pain in the short term and it does nothing in the long term. Science Daily reports that the researchers treated 300 adults with chronic knee pain either with needle acupuncture, laser acupuncture (hitting acupuncture spots with a low-intensity laser beam), sham laser acupuncture, or no treatment at all (the […]

    Read more →
  • Fitness Pain Karate Masters Have Faster Brains

    Karate Masters Have Faster Brains

    Researchers have known for a while that the power of a karate blow is not all about strength. Rather, it’s about fine coordination between wrists and shoulders. Now researchers at University College in London have learned where that better coordination comes from: a better brain. A University College news release reports that researchers looked for differences in brain structure between 12 karate practitioners with a black belt rank and an average of 13.8 years’ karate experience, and 12 control subjects […]

    Read more →
  • Fitness Pain Exercise Is Bad For Your Teeth, Maybe

    Exercise Is Bad For Your Teeth, Maybe

    OK, this is surprising. As Gretchen Reynolds points out in the New York Times, exercise may be good for every part of your body but one: your teeth. Reynolds reports that the good health/bad teeth dichotomy came to the attention of many last year when a study was published in The British Journal of Sports Medicine, in which dentists who examined 278 athletes at the 2012 Summer Olympics in London reported that a majority displayed “poor oral health,” including high levels […]

    Read more →