I would definitely question that statement. What principles of physics are you basing that on? I think you may be confusing it with the situation where a car driver is repeatedly accelerating and braking.
Mikkel
Efficiency evidence: frog vs flutter?
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I would definitely question that statement. What principles of physics are you basing that on? I think you may be confusing it with the situation where a car driver is repeatedly accelerating and braking.
Mikkel
Bob DBF
Contributor
One reason I avoid cameras. Were you in surge or current? I've noticed that I've gotten in some contorted positions trying to stay on course and in trim when the water around me is in flux. In those cases I may be using my fin more as a rudder than propulsion. The other time this might happen is when I'm "resting" muscles and try to propell myself, it's ugly because it is no known kick, but I have avoided cramps in the water my whole life.
Bob
CT-Rich
Contributor
Physics in a vacuum is different than in air and water is 200 time denser than air. The lower the speed the less effect drag has on an object. Double the speed and you will quadruple the resistance (or something like that). The different kicks are going to effect the efficiency that you convert glucose and oxygen into movement to overcome the resistance of water. A porpoise kick will accelerate you to a higher speed but at a cost. A relaxed slow flutter will push you forward, but is not the best for turning or leaving the bottom undisturbed. Novice divers like the flutter kick because they can control depth without controlling buoyancy. Frog kicks are terrible for speed but allow for easy turns and keep your feet away from the bottom. They also have a relatively low energy requirement because you are expending a minimum amount of energy to maneuver. However, to get most effective use, you need to control buoyancy.
Well then maybe a physics refresher on kinetic energy is needed. Kinetic energy - Wikipedia
The energy to accelerate a mass depends on the mass and rate of change. Which is why jackrabbit starts are less efficient than gradual starts and why trains take a long time to get up to speed. It takes 4x energy to double speed. Once at velocity it takes zero energy to maintain it, absent external forces. In practice, when maintaining you are only accelerating against the frictional drag.
Common sense should tell you that accelerating to a higher velocity AND against friction is greater than simply accelerating against friction alone.
My thoughts on this... Based on my 10-15 years of competitive swimming (though I sucked), and quite some time spent swimming later on.
First, you'll need to define efficiency... Are you looking at liters per minute, liters per meter? You might not even do the same dive.
Flutter is likely faster. Depending on the person. At least, when there's no gear on.
When there's resistance to fight against, in my experience, you're better off with frog kick. Some background on this. When I trained for swimming, there was that big guy that would simply destroy me on any race (but we weren't in same category). At some point in the training, we did some "band training", with a rubber band pulling us towards one end of the pool, and we had to stay as far and as long as possible from the side.
On the first try, everyone but me went for freestyle, because to me it seemed obvious to go with the technique I mastered, which was breast stroke. Well, I was the one that went the farthest and longest. Then, the trainer suggested to others to not use freestyle... and everybody got farther than he did on his first try (except me).
So yeah, to me, if you're pulling something heavy, you're better off not using flutter kicks.
But at the end of the day, I hardly ever had a dive I considered exhausting and/or too short, so I'm really not worried about this whole SAC thing.
First, you'll need to define efficiency... Are you looking at liters per minute, liters per meter? You might not even do the same dive.
Flutter is likely faster. Depending on the person. At least, when there's no gear on.
When there's resistance to fight against, in my experience, you're better off with frog kick. Some background on this. When I trained for swimming, there was that big guy that would simply destroy me on any race (but we weren't in same category). At some point in the training, we did some "band training", with a rubber band pulling us towards one end of the pool, and we had to stay as far and as long as possible from the side.
On the first try, everyone but me went for freestyle, because to me it seemed obvious to go with the technique I mastered, which was breast stroke. Well, I was the one that went the farthest and longest. Then, the trainer suggested to others to not use freestyle... and everybody got farther than he did on his first try (except me).
So yeah, to me, if you're pulling something heavy, you're better off not using flutter kicks.
But at the end of the day, I hardly ever had a dive I considered exhausting and/or too short, so I'm really not worried about this whole SAC thing.
Interesting. Power and speed are not the same thing. There is a theory about using power at the start to get things moving, then change to speed.
Your resistance band seems to test power and as the band is stretched, resistance increases and more power is needed to stretch it further. Pulling something heavy in water ? Assuming it is relatively buoyancy neutral, the resistance decreases once you get moving. Maybe use power like the frog kick to start getting it moving forward and then switch to flutter ?
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Kick the way you want.
Flutter or scissor kick most of the time for me.
Interesting though to see the different opinions.
Flutter or scissor kick most of the time for me.
Interesting though to see the different opinions.
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